FLOW MACHINE WITH COOLING CHANNEL

Description

[0001] The invention relates to a turbomachine, in particular a compressor or a turbine, with a drive shaft coupled to an electric machine, in particular an electric motor or a generator, which directly or indirectly drives a fluid wheel, in particular a compressor wheel or a turbine wheel, wherein the electric machine has a stator which is received and mounted in a housing, wherein the stator is connected or connectable to a power supply arranged outside the housing via connecting lines, wherein the power supply is housed outside the housing in a receiving area of ​​an electronics housing, and wherein a cooling channel is provided which has an inlet line and an outlet line and which is designed to carry a cooling fluid, in particular a coolant.

[0002] Such a compressor is known from US 2019 / 0195240 A1. This document describes a compressor that can be used as a turbocharger in motor vehicles. The compressor has a housing to which a compressor housing is flanged on one side. On the opposite side, an inverter housing is attached to the housing as an electronics housing. An electric motor is arranged in the housing, comprising a rotor and a stator. The rotor is equipped with permanent magnets of the electric motor and carries a compressor wheel at one end, which is located in the compressor housing. The stator is contacted by its stator windings to current guide rails located in the transition area between the housing and the inverter housing. A contact pin, sealed and passed through a feedthrough in the inverter housing, is connected to the current guide rail.At its end opposite the current guide rail, the contact pin is connected to another current rail. This current rail is then screwed to a terminal block of an inverter power supply for the electric motor, which is housed in a compartment within the electronics enclosure. The electronics enclosure has a base with a recess that opens into the compartment. This recess can be sealed with a module plate from the power supply, creating a cooling channel through which a cooling medium can circulate to cool the power supply. The compressor, as described above, occupies a relatively large installation space and has a complex design.

[0003] US patent 2019 / 0195212 A1 discloses an electrically driven compressor. This compressor again features a housing in which the stator of an electric motor is held. Radially external to a drive shaft that carries a compressor wheel, an electronics housing is provided. This electronics housing forms a receptacle into which the power supply for the electric motor can be installed.

[0004] The prior art also includes documents US 2004 / 251869 A1, FR 3 060 896 A1 and EP 0 878897 A1.

[0005] The object of the invention is to provide a turbomachine of the type mentioned above which, with a compact design, enables efficient cooling of the power supply for the electric machine.

[0006] This problem is solved by a turbomachine according to claim 1.

[0007] By providing, according to the invention, that the cooling channel is formed as a cavity within the housing, the number of parts can be reduced. Furthermore, this significantly reduces the required installation space occupied by the turbomachine. In particular, the cavity can be designed as a closed space, bounded solely by the housing material. The cavity can be formed within the housing and connected to the environment only via one or more inlet and outlet lines for the coolant. In this respect, the cooling channel can be formed as a closed cavity within the housing. Such a housing can be manufactured easily, for example, as a casting, preferably using a lost core that forms the cavity.This design also achieves effective cooling of the power supply unit located within the electronics housing, particularly the power electronics and / or the control unit (controller) for the electric motor. For this purpose, the first cooling channel section is positioned between the stator and the electronics housing. This allows both the stator and the electronics to dissipate at least some of their heat loss into the cooling channel, while simultaneously supporting a space-saving design. If a single-piece design of the housing and electronics housing is used, the number of parts and assembly costs are significantly reduced.

[0008] For the purpose of effective heat dissipation, it may be provided in particular that the projections of the stator and the cooling channel in the axial direction of the drive shaft overlap at least partially in a common plane, and / or that the projections of the receiving space or the power supply arranged in the receiving space and the cooling channel overlap at least partially in the axial direction of the drive shaft in a common plane.

[0009] To further improve stator cooling, the invention provides that the cooling channel has a second cooling channel section, which is arranged at least partially circumferentially around the stator. Accordingly, the stator can transfer heat loss into the cooling channel both circumferentially and axially.

[0010] A turbomachine according to the invention can also be designed such that the first and second cooling channel sections of the cooling channel merge into one another in a cross-sectional view through the axis of the drive shaft, forming a common cavity. Such a design is easy to manufacture. However, it is also conceivable that the first and second cooling channel sections of the cooling channel are formed by two spatially separate channel structures. The two cooling channel sections can then be routed separately to suitable locations on the housing, enabling particularly effective heat dissipation. Naturally, within the scope of the invention, it is also possible to provide not only two cooling channel sections but also one or more additional cooling channel sections.

[0011] According to the invention, a particularly space-saving design for the turbomachine is achieved by the fact that the housing and the electronics housing have a common housing base, and that the cooling channel extends at least partially within the housing base.

[0012] For example, it may be provided that the cooling channel is limited on its side facing the electronics housing by a wall section of the housing, in particular the housing base. According to the invention, the cooling channel is limited on its side facing the stator by a wall area of ​​the housing, in particular the housing base.

[0013] If the stator and power supply are arranged accordingly, they can transfer their waste heat via the wall area or wall section.

[0014] For this purpose, the design of the turbomachine can be such that an electrical component, in particular part of the power supply, is arranged on the side of the wall section facing away from the cooling channel, preferably in contact with the wall section. The contact between the wall section and the electrical component can be achieved by direct physical contact with the wall section. Alternatively, indirect contact is conceivable, with a thermally conductive intermediate element being inserted between the wall section and the electrical component. For example, a thermally conductive paste could be used as this intermediate element. Furthermore, both direct and indirect contact between the electrical component and the wall section are possible.

[0015] A particularly preferred embodiment of the invention is such that at least one projection is formed on the wall section and / or wall area, which projects beyond the wall section and / or wall area and extends into the cooling channel. These projections form turbulators that ensure improved mixing of the coolant in the cooling channel. For example, the projections can be curved on their outer circumference, for instance, cylindrical, for this purpose. Furthermore, the projections increase the available surface area for heat exchange.

[0016] The projections can, for example, be assigned a further functionality if a mounting receptacle is provided in the wall section, extending into the projection and accessible from the receiving space of the electronics housing, and a fastening element is inserted into the mounting receptacle, in particular for attaching the power supply or a part thereof to the wall section, and / or if a mounting receptacle is provided in the wall area, extending into the projection and accessible from the receiving space of the housing, and a fastening element is inserted into the mounting receptacle, in particular for attaching the stator to the wall area. In such embodiments of the invention, the wall section and / or the wall area can be designed to be particularly thin-walled.Nevertheless, the mounting points for the power supply or the stator can still be implemented on the wall section and / or wall area to ensure favorable heat transfer.

[0017] Particularly advantageous results for effective heat transfer across the wall section or wall area have been obtained when the wall thickness of the wall section and / or the wall thickness of the wall area extending in the axial direction of the drive shaft is at least 2.5 mm and at most 4 mm, particularly preferably 2.5 mm to 3 mm, wherein the material forming the wall section and / or the material forming the wall area is a non-magnetizable metallic material, in particular non-magnetic light metal alloys, e.g. aluminum or an aluminum alloy, titanium or a titanium alloy, magnesium or a magnesium alloy, or plastic, in particular a fiber-reinforced plastic.

[0018] According to the invention, the stator is at least partially embedded in a potting compound within the housing, and the potting compound is in contact with the housing, preferably with the housing base. Thus, the stator is embedded in a potting compound within the housing. This ensures that the stator is reliably fixed in the housing. Furthermore, the potting compound can act as a heat conductor. This allows the power loss generated during operation to be dissipated as heat via the potting compound into the housing and the cooling channel. Assembly is straightforward. The stator is placed in the housing, and then the potting compound is poured into the housing so that the stator is embedded in the potting compound at the desired locations. Finally, the potting compound is allowed to harden.A plastic compound, possibly a thermoset, consisting of a resin and hardener mixture, can be used as the potting compound. This material can be mixed to a correspondingly low viscosity and flows even into inaccessible areas of the housing to embed the stator. The potting compound is preferably electrically non-conductive or insulating. Preferably, the potting compound is an epoxy resin with high thermal conductivity, e.g., a ceramic-filled epoxy resin.

[0019] According to the invention, the potting compound not only partially encases the stator but also simultaneously forms a sealing element that seals the connection lead of the electric machine's stator winding against a feedthrough in the housing. The feedthroughs allow the connection leads to the stator windings to be routed into the electronics housing and connected to the stator windings. The feedthrough can, for example, form a connection between the housing and the electronics housing. Accordingly, the sealing element can be manufactured in a single step together with the stator's fixation with the potting compound. This eliminates the need for complex additional components, such as those required in the prior art. In this way, the number of parts and the assembly effort are significantly reduced.Preferably, the sealing element is formed as a single unit with the area of ​​the potting compound that at least partially accommodates the stator. This creates a fixed connection between the stator and the connecting lines passing through the bushings. This fixed connection increases operational reliability. In particular, it creates a unit that is less susceptible to corrosion and especially to vibrations.

[0020] According to a preferred embodiment of the invention, the connecting leads, in particular each connecting lead per phase, can be formed in one piece and led out of the housing through the feedthrough. The connecting lead can be easily fixed in the feedthrough with the sealing piece. Furthermore, the number of electrical connection points is reduced, making the entire assembly less susceptible to corrosion and vibration.

[0021] Particularly for compressors in the form of turbochargers, it has been found that effective heat dissipation from the stator can be sufficiently ensured if the potting compound has a thermal conductivity in the range between 0.5 W / (m*K) and 5 W / (m*K).

[0022] Good accessibility of the electronics housing for assembly and maintenance purposes can be achieved if the electronics housing has a side wall that forms an opening opposite the housing, the opening being closed by a preferably removable cover, and preferably the side wall having a lateral opening for receiving a power supply line.

[0023] Good accessibility of the housing for assembly and maintenance purposes can be achieved if the housing is designed to form an opening opposite the electronics housing, with the opening being closed by a preferably removable cover.

[0024] The invention will be explained in more detail below with reference to exemplary embodiments illustrated in the drawings. The drawings show: Figure 1 in side view and in section an electrically driven compressor, Figure 2 a partial section along the in Figure 1 with section line marked II-II, Figure 3 a detailed presentation of a second design variant, Figure 4 a detailed presentation of a third design variant, Figure 5 a in Figure 1 Detail marked with V Figure 6 a detailed representation of a variant according to the invention in a Figure 1 area marked with VI and Figure 7an alternative design variant of an electrically operated compressor.

[0025] Figure 1 Figure 1 shows an electrically driven compressor according to the invention. For the purposes of this invention, "compressor" refers in particular to turbochargers. This can also include exhaust gas turbochargers. In exhaust gas turbochargers, a compressor wheel 14 and a turbine are coupled to a drive shaft 13. The turbine is operated in the exhaust gas stream, particularly from an internal combustion engine. Compressors according to the invention can also be used to supply fuel cells with a gas stream.

[0026] How Figure 1As shown, the compressor has a drive shaft 13. This drive shaft 13 is rotatably mounted in a housing 20 by means of bearings 13.1, 13.2. One or both bearings 13.1, 13.2 can be rolling element bearings, for example, ball bearings. Within the scope of the invention, it is further conceivable that one or both bearings 13.1, 13.2 are designed as hydrodynamic sliding bearings.

[0027] The housing 20 has a housing base 26. One of the two bearings 13.1, 13.2 is preferably mounted in the housing base 26.

[0028] The drive shaft 13 carries a rotor 11 of an electric machine 10, namely an electric motor. The rotor 11 is fixedly connected to the drive shaft 13. The rotor 11 is equipped with permanent magnets that are distributed around or surrounding the circumference of the rotor 11.

[0029] The electric motor 10 further comprises a stator 12. This stator 12 preferably has a stator core 12.4, for example a laminated core composed of laminated laminations. Preferably, the laminated core is designed as a stamped laminated core. The stator has stator windings 12.6 (see Figure 2 These stator windings are each formed by a wire. Each of these stator windings has a connecting lead 12.1. Depending on the current and frequency, the connecting lead 12.1 is formed by a wire, a cable, or a busbar. The second end of the connecting lead 12.1 is connected to the housing 20 via a ground connection.

[0030] The drive shaft 13 carries a fluid impeller 14 in the form of a compressor wheel at its end. The fluid impeller 14 is non-rotatably connected to the drive shaft 13 by means of a fastening element 16.

[0031] How Figure 1As shown, the impeller 14 is housed in a compressor casing 40. The compressor casing 40 has an intake area 41. A gas, in this exemplary embodiment air, can be drawn in through this intake area 41. The gas is compressed by the impeller 14 and guided into a compressor channel 42 that runs spirally within the compressor casing 40. The compressor channel 42 has an outlet. The compressed gas can be discharged through this outlet and supplied to a driven machine, for example an internal combustion engine or a fuel cell.

[0032] The housing 20 is pot-shaped and has a circumferential side wall 27 that rises from the housing base 26.

[0033] A cavity is incorporated into the housing 20, forming a cooling channel 21.

[0034] The cooling channel 21 is designed as a cavity that is completely surrounded by the material forming the housing 20. In particular, the cooling channel 21 is molded into the housing 20 as a single piece.

[0035] The cooling channel 21 extends at least partially in the area of ​​the housing base 26 and preferably at least partially in the area of ​​the wall 27. The cooling channel 21 can be designed such that it essentially surrounds the receiving area of ​​the housing 20 in a ring shape.

[0036] According to the invention, the channel 21 has a first cooling channel section 21.3, which is arranged between the stator 12 and the receiving space 54 of the electronics housing 50. The projections of the stator 12 and the first cooling channel section 21.3 in the axial direction of the drive shaft 13 into a common plane overlap at least partially, as shown. Figure 1 shows.

[0037] Preferably, the projection of the receiving space 54, in particular the area of ​​the receiving space 54 in which the power supply 60 is housed, and the projection of the first cooling channel area 21.3 in the axial direction of the drive shaft 13 overlap at least partially in a common plane. In the illustrated embodiment, the power supply 60 comprises, for example, a printed circuit board 63 and electronic components 61 mounted thereon. In particular, the projection of the printed circuit board 63 and the projection of the first cooling channel area 21.3 in the axial direction of the drive shaft 13 overlap at least partially in a common plane.

[0038] How Figure 1 As further shown, a second channel area 21.4 of the cooling channel 21 is provided, which surrounds the stator 12 at least partially in the circumferential direction of the stator 12.

[0039] The first cooling channel section 21.3 transitions directly into the second cooling channel section 21.4. However, it is also possible that the first cooling channel section 21.3 and the second cooling channel section 21.4 are at least partially separated from each other within the housing 20.

[0040] How Figure 2 As can be seen, the cooling channel 21 has a supply line 21.1 and a return line 21.2. The annular contour of the cooling channel 21 is interrupted in the area between the supply line 21.1 and the return line 21.2. The supply line 21.1 can be connected to a coolant supply via an inlet line 28.1, and the return line 21.2 via an outlet line 28.2. Accordingly, the inlet line 28.1 and the outlet line 28.2 form connection points for the coolant supply. The coolant can flow into the supply line 21.1 via the inlet line 28.1 and through the cooling channel 21. The coolant leaves the cooling channel 21 through the return line 21.2 and the outlet line 28.2.

[0041] As the Figure 1 and 2 As can be seen, the side wall 27 forms an inner wall 22 that surrounds the receiving space of the housing 20. The inner wall 22 is directly adjacent to the cooling channel 21.

[0042] The stator 12 is positioned in the receiving space of the housing 20. A potting compound 70 is used to secure the stator 12 in the receiving space. This potting compound 70 fills at least part of the receiving space of the housing 20. The potting compound 70 may form two receiving areas 23.1 and 23.2. The first receiving area 23.1 is located between the housing base 26 and the stator 12. The second receiving area 23.2 is located between the impeller 14 and the stator 12.

[0043] The stator 12, with its core, rests against the side wall 27 at its outer circumference. Additionally, a stop and a centering element are formed on the side wall 27. The stator 12 is supported by this stop and centering element in the axial direction of the drive shaft 13. Thus, the stator 12 can be inserted into the receiving area of ​​the housing 20 through a housing opening 24. The insertion movement is limited in the axial and radial directions by the stop and centering element, respectively, so that the stator 12 is precisely aligned in the housing 20.

[0044] The potting compound 70 is used to fix the stator 12. The potting compound 70 also forms a sealing element 71, which fills a passage 25 in the housing base 26. The sealing element 71 is formed in one piece with at least one of the receiving areas 23.1, 23.2. For manufacturing, a liquid potting compound 70 can be poured into the receiving space of the housing 20 so that the corresponding receiving areas 23.1, 23.2 and the passage 25 are filled. The potting compound 70 is then allowed to harden, resulting in a solid body of potting compound.

[0045] How Figure 1As can be further seen, the connecting leads 12.1 of the stator windings are guided through the feedthrough 25 and embedded in the sealing piece 71. The sealing piece 71 thus forms a seal through which the connecting leads 12.1 are sealed and lead out of the housing 20. The adhesive bond between the sealing piece 71 and the connecting leads 12.1 provides not only a seal but also strain relief for the connecting leads 12.1.

[0046] Figure 1 Figure 25 shows that the feedthrough 25 can be configured as a through-hole in the housing base 26. The feedthrough 25 has two openings 25.1, 25.2, between which the sealing element 71 extends. The sealing element 71 may completely or partially fill the area between the openings 25.1, 25.2.

[0047] How Figure 1As further shown, the housing 20 can be closed with a cover 30 in the area of ​​its housing opening. A sealing element receptacle is provided for the sealed connection of the cover 30 to the housing 20, which accommodates a gasket. The cover 30 is connected to the housing 20 by means of fastening elements (not shown). The cover 30 has an opening 32 through which the drive shaft 13 passes.

[0048] The compressor further comprises an electronics housing 50. The electronics housing 50 is bounded by a circumferential side wall 51. Preferably, this side wall 51 is integrally connected to the housing base 26. The electronics housing 50 can also be cup-shaped. It has an opening that is bounded by the circumferential side wall 51. The opening of the electronics housing 50 is located opposite the housing opening 24 of the housing 20. The opening of the electronics housing 50 can be closed with a cover 52. For this purpose, the side wall 51 can be provided with threaded receptacles. The cover 52 has screw receptacles aligned with the threaded receptacles. Fastening screws 53 pass through these receptacles and are screwed into them. Preferably, the cover 52 is sealed against the side wall 51.

[0049] The electronic housing 50 surrounds a receiving area 54. A printed circuit board 63 is arranged in this receiving area 54. The printed circuit board 63 preferably contacts the housing base 26 and can be connected to it via fastening means 62. In this way, a thermally conductive contact is created between the housing base 26 and the printed circuit board 63. Heat loss at the printed circuit board 63 can then be dissipated via the housing base 26 into the cooling channel 21.

[0050] Preferably, a thermally conductive paste is also arranged between the circuit board 63 and the housing base 26 to reduce thermal resistance. This further improves the cooling performance.

[0051] It is also conceivable that a heat distribution element, for example a plate-shaped element made of a highly thermally conductive material such as copper or aluminum, or a vapor chamber, is provided between the circuit board 63 and the housing base 26. The use of a so-called heat spreader, as is generally known from semiconductor technology, is conceivable here. This heat distribution element can also be additionally coated on both sides facing the circuit board 63 and the housing base 26 with a thermally conductive paste to ensure improved contact with these components.

[0052] How Figure 1As shown, the housing base 26 may also have one or more projections 26.1 that extend into the cooling channel 21. The projections 26.1 preferably extend from a wall section 26.2 of the housing base 26, which adjoins the receiving space 54 of the electronics housing 50, in particular the area in which the printed circuit board 63 is held. This increases the effective surface area for heat dissipation. It is particularly preferred that the following configuration is used: Figure 5 shows that the projection 26.1 has a mounting receptacle 26.4, for example in the form of a screw receptacle. In The fastening element 62, designed as a fastening screw, is screwed into the thread of this screw receptacle. This allows the transition area of ​​the housing base 26 between the receiving chamber 54 and the cooling channel 21 to be designed with thin walls for the purpose of improved heat transfer.

[0053] Figure 1The figure further shows that the cooling channel 21 in the housing 20 is designed such that a wall section 26.3 is formed in the transition area between the receiving space of the housing 20 and the cooling channel 21. The wall section 26.3 is also thin-walled to enable good heat transfer to the stator 12.

[0054] Preferably, the wall thickness of wall section 26.2 and / or wall region 26.3 is between 2.5 mm and 4 mm, wherein the material of the housing base 26 is preferably a non-magnetizable material, e.g., aluminum or an aluminum alloy, titanium or a titanium alloy, or magnesium or a magnesium alloy. Furthermore, the projections 26.1, which extend into the cooling channel 21, form elements that influence the flow in the cooling channel 21. The projections 26.1 thus form turbulators that ensure better mixing of the cooling medium (e.g., cooling water) in the cooling channel 21. To ensure that the projections 26.1 do not present excessive flow resistance to the coolant in order to achieve this objective, they can have a cylindrical outer circumference. Alternatively, it is also conceivable that the projections 26.1 have a flow-optimized, elongated shape along the flow direction of the coolant, e.g.,have an elliptical cross-section.

[0055] In addition to or as an alternative to the projections 26.1 extending from the wall section 26.2 of the housing base 26, the invention provides that at least one projection 26.1 extends from the wall area 26.3. In a particularly advantageous embodiment, it can be provided that, as shown in Figure 6 The projections 26.1 extending from wall section 26.2 are shown to project into both the cooling channel 21 and the receiving space of the housing 20. This allows for improved heat dissipation from the stator 12 into the coolant.

[0056] According to the invention, at least one of the projections 26.1 extending from the wall section 26.2 contacts the stator 12, specifically the stator core 12.4. The projections 26.1 extending into the receiving space of the housing 20 can form axial stops for the stator core 12.4. In the Figure 6In the illustrated variant of the invention, the projections 26.1 extending from the wall section 26.2 into the receiving space of the housing 20 contact the stator core 12.4 in the area of ​​the stator teeth.

[0057] The side wall 51 of the electronics housing 50 can be provided with an opening 57. A power cable 56, e.g., via a plug connector, can be routed through this opening 57. The power cable 56 connects electronic components 61 of the power supply 60, which are arranged on the circuit board 63, to an external power supply. In this embodiment, the power supply 60 is equipped with an inverter. The inverter transforms the direct current supplied by the power cable 56 into an alternating voltage, which is supplied to the stator windings 12.6 via the connecting leads 12.1. A connector 55, for example in the form of a socket, is used to relieve strain on the power cable 56 and to facilitate the compressor's mounting. This connector can be screwed to the side of the electronics housing 50.

[0058] The circuit board 63, together with the electronic components 61, can be inserted into the receiving area 54 through the open side of the electronic housing 50.

[0059] How Figure 1 As shown, the connecting lines 12.1 have line ends 12.2. These are electrically contacted with the circuit board 63 via a connection 12.3.

[0060] Connection 12.3 can, in the simplest case, be formed by an electrically conductive, material-bonded connection, preferably a solder joint. A crimp connection is also conceivable here.

[0061] How Figure 3 As shown, it can also be provided that the connecting leads 12.1 with their leads 12.2 are led to a connector element 12.5 and connected to it. The connector element 12.5 can then be plugged onto a mating connector of the circuit board 63.

[0062] Figure 4Figure 1 shows another embodiment. As this drawing shows, the conductor ends 12.2 of the connecting conductors 12.1 terminate in the area behind the sealing piece 71 and protrude beyond the opening 25.1 of the bushing 25. A connector 80 is embedded in the potting compound 70 forming the sealing piece 71 and is held captive within it by means of the potting compound 70. The connector 80 has a socket 81 within which the conductor ends 12.2 terminate. The connecting conductors 12.1 pass through a flange 82 of the connector 80. The flange 82 carries retaining elements 83. The retaining elements 83 are inserted into the potting compound 70 of the sealing piece 71 and anchored therein. Preferably, the retaining elements 83 are held in the potting compound 70 by a positive locking mechanism. For this purpose, they have projections that protrude from the retaining elements 83 transversely to the longitudinal extent of the connecting conductors 12.1.

[0063] The socket 81 forms a plug for receiving a receptacle 84. The receptacle 84 is mounted on the circuit board 63. The receptacle 84 can be connected to the socket, e.g., by plugging them together, so that the wire ends 12.2 and the circuit board 63 are electrically connected. A cable is attached to the mating connector, which leads to and is connected on the circuit board 63.

[0064] Figure 7Figure 1 shows another electrically driven compressor in the form of an exhaust gas turbocharger. The electronics housing 50 is arranged radially outside the housing 20. The electronics housing 50 partially encompasses the housing 20 in the circumferential direction. In this embodiment, the connecting lines 12.1 extend in a direction perpendicular to the axial direction to be guided into the electronics housing 50, which is arranged radially outside the housing 20. The connecting lines 12.1 can be guided from the housing 20 into the electronics housing 50 through a single opening 25, or each connecting line 12.1 can be guided from the housing 20 into the electronics housing 50 through a separate opening 25. In the [figure / ... Figure 7 In the illustrated design variant, the electronic housing 50 is screwed onto the housing 20.

[0065] As the foregoing illustrates, the invention relates to a compressor with a drive shaft coupled to an electric motor, which directly or indirectly drives an impeller, wherein the electric motor has a stator which is received and mounted in a housing, wherein the stator is connected or connectable to a power supply located outside the housing via connecting lines, wherein the power supply is housed outside the housing in a receiving area of ​​an electronics housing, and wherein a cooling channel is provided which has an inlet line and an outlet line and which is designed to carry a cooling fluid, in particular a coolant.To achieve a compact design, the invention provides that the housing and the electronics housing are joined in one piece, and that the cooling channel has a first cooling channel section which is arranged at least partially between the stator and the electronics housing and which is formed as a cavity in the housing. This arrangement of the cooling channel 21 to the stator 12 and the electronics housing 50 also results in particularly effective cooling.

Claims

1. Turbomachine, in particular compressor or turbine, having a drive shaft (13) which is coupled to an electrical machine, in particular an electric motor (10) or a generator, and which drives a flow wheel, in particular a compressor wheel (14) or a turbine wheel, indirectly or directly, the electrical machine (10) having a stator (12) which is accommodated in a receiving space of a housing (20) and is fastened therein, the stator windings of the stator (12) being connected via connecting leads (12.1) to a power supply (60) arranged outside the housing (20), the power supply (60) being accommodated outside the housing (20) in a receiving region (54) of an electronics housing (50), and a cooling channel (21) being provided which has an inlet line (28.1) and an outlet line (28.2) and which is designed to carry a cooling fluid, in particular a cooling liquid, wherein the housing (20) and the electronics housing (50) are connected to one another, preferably integrally connected to one another, and wherein the cooling channel (21) has a cooling channel region (21.3, 21.4) which is arranged at least partially between the stator (12) and the electronics housing (50) and which is molded as a cavity in the housing (20), wherein the housing (20) and the electronics housing (50) have a common housing bottom (26), and wherein the cooling channel (21) extends at least partially within the housing bottom (26), wherein the cooling channel (21) is bounded on its side facing the stator (12) by a wall region (26.3) of the housing (20), in particular of the common housing bottom (26), the stator (12) being at least partially embedded in a potting compound (70) in the housing (20), the potting compound (70) being in contact with the housing (20), preferably with the housing bottom (26), and wherein the potting compound (70) at least partially accommodates the stator (12) and forms a sealing piece (71) which seals the connecting leads of the stator windings of the electrical machine with respect to a bushing (25) of the housing, characterized in that at least one projection (26.1) is formed on the wall region (26.3) and projects beyond the wall region (26.3) into the receiving space of the housing (20) and contacts the stator core (12.4).

2. Turbomachine according to claim 1, characterized in that the projections of the stator (12) and of the cooling channel (21) in the axial direction of the drive shaft (13) overlap at least in some areas in a common plane, and / or that the projections of the receiving region (54) or of the power supply (60) arranged in the receiving region (54) and of the cooling channel (21) in the axial direction of the drive shaft (13) overlap at least in some areas in a common plane.

3. Turbomachine according to claim 1 or 2, characterized in that the cooling channel (21) has a second cooling channel region (21.4) which is arranged around the stator (12) at least in some regions in the circumferential direction and / or in that the cooling channel (21) has a first cooling channel region (21.3), which is arranged at least in some regions on the side of the stator (12) facing away from the flow wheel (14).

4. Turbomachine according to claim 3, characterized in that the first cooling channel region (21.3) and the second cooling channel region (21.4) of the cooling channel (21) merge into one another in a sectional view through the axis of the drive shaft (13), forming a common cavity, or in that the first cooling channel region (21.3) and the second cooling channel region (21.4) of the cooling channel (21) are formed by two spatially separate channel structures.

5. Turbomachine according to one of claims 1 to 4, characterized in that the cooling channel (21) is bounded on its side facing the electronics housing (50) by a wall section (26.2) of the housing (20), in particular of the housing bottom (26).

6. Turbomachine according to claim 5, characterized in that an electrical component, in particular a part of the power supply (60), is arranged on the side of the wall section (26.2) facing away from the cooling channel (21), it being preferably provided that the electrical component contacts the wall section (26.2).

7. Turbomachine according to claim 5 or 6, characterized in that at least one projection (26.1) is formed on the wall section (26.2) and / or the wall region (26.3), which projection projects beyond the wall section (26.2) and / or the wall region (26.3) and which projects into the cooling channel (21).

8. Turbomachine according to claim 7, characterized in that a fastening receptacle (26.4) is provided in the wall section (26.2), which extends into the projection (26.1) and which is accessible from the receiving region (54) of the electronics housing (50), and in that a fastening means (62) is inserted into the fastening receptacle (26.4), in particular for fastening the power supply (60) or part of the power supply (60) to the wall section (26.2), and / or in that a fastening receptacle is provided in the wall region (26.3), which extends into the projection (26.1) and which is accessible from the receiving space of the housing (20), and in that a fastening means is inserted into the fastening receptacle, in particular for fastening the stator (12) to the wall region (26.3).

9. Turbomachine according to one of claims 1 to 8, characterized in that the wall thickness of the wall section (26.2) extending in the axial direction of the drive shaft (13) and / or the wall thickness of the wall region (26.3) extending in the axial direction of the drive shaft (13) is at least 2.5 mm and at most 4 mm, wherein the material forming the wall section (26. 2) and / or the material forming the wall region (26.3) is a non-magnetizable metal material, in particular aluminum or an aluminum alloy, titanium or a titanium alloy, magnesium or a magnesium alloy or plastic, in particular a fiber-reinforced plastic10. Turbomachine according to one of claims 1 to 9, characterized in that a flow wheel (14) is non-rotatably mounted on the drive shaft (13).

11. Turbomachine according to one of claims 1 to 10, characterized in that the potting compound (70) has a thermal conductivity in the range between 0.5 W / (m*K) and 5 W / (m*K).

12. Turbomachine according to one of claims 1 to 11, characterized in that the electronics housing (50) has a side wall (51) which forms an opening opposite the housing (20), the opening being closed by a preferably removable cover (52), the side wall (51) preferably having a lateral opening (57) for receiving a power supply line (56).

13. Turbomachine according to one of claims 1 to 12, characterized in that the housing (20) forms an opening opposite the electronics housing (50), the opening being closed by a, preferably removable, cover (30).