WO2005113960A1

WO2005113960A1 - Electric power connector for electric motor

Info

Publication number: WO2005113960A1
Application number: PCT/EP2004/005148
Authority: WO
Inventors: Philippe Noelle; Toshihiro Sato; Naoki Oniishi; Akira Tsunoda
Original assignee: Honeywell International Inc.
Priority date: 2004-05-13
Filing date: 2004-05-13
Publication date: 2005-12-01

Abstract

An electric motor (9) for inserting into a center housing (7) of a turbocharger (1) or an electrically driven compressor, and driving a compressor wheel (6) accommodated in a compressor housing (5) is provided, said electric motor being supplied with electric power through at least one motor connector element (35) wherein at least a part of the motor connector element (35) protrudes from a contact plane (38) between the center housing (7) and the compressor housing (5) toward the side of the electric motor (9). Preferably, said part of the motor connector element (35) protrudes to a space radially outside of the electric motor (9).

Description

Electric Power Connector For Electric Motor

The invention relates to an electric motor for inserting into a center housing of a turbocharger or a housing of an electrically driven compressor, and connectable via connector elements to a power source, and to a turbocharger comprising the electric motor inserted into the center housing for electrically assisted compression of air for an engine .

Turbochargers are well known and widely used in connection with combustion engines. Exhaust gas from the engine is supplied to a turbine and drives a turbine wheel which drives a compressor wheel. The compressor wheel compresses air and discharges it into combustion chambers of respective cylinders of the engine. The thus compressed air contains a larger amount of oxygen to enhance the combustion of fuel and thus to generate more power. However, as exhaust gas having less energy is supplied to the turbine wheel when the rotational speed of the engine is low, the pressure increase of the air supplied to the combustion chambers is low. This results in a so-called „turbo-lag" for low engine speed ranges in which an engine output is low. A known solution for overcoming this turbo- lag is to provide an electric motor for the turbocharger which accelerates the compressor wheel when the rotational speed of the engine is low, so that a sufficient high pressure of the air supplied to the combustion chambers is ensured.

In the international application No. PCT/EP03/0393 , there is described a turbocharger shown in Figs. 8 and 9 having an electric motor 50 for assisting the rotation of a rotor. The turbocharger has a shaft 51 carrying a turbine wheel 54 accommodated in a turbine housing and a compressor wheel 52 accommodated in a compressor housing 53. The shaft 51 is supported by a bearing accommodated in a center housing 56 and the electric motor 50 is accommodated in an electric motor cartridge 57 which is received in the center housing 56 and is fixed by the compressor housing 53. The electric motor 50 is supplied with electric power through lead wires 58 which pass through the walls of the cartridge 57 and the center housing 56 in a substantially radial direction. As shown in Fig. 8, lead wires 58 have to pass edges 59 of the center housing and have to pass through a cooling water cavity 60 of the center housing 56.

Accordingly, there is a need to provide an improved power connection for an electric motor in a turbocharger.

According to one aspect of the invention, the above need is met with an electric motor having the features of claim 1. Modifications of the electric motor are set forth in the sub claims 2 to 16.

According to another aspect of the invention, the above need is met with a turbocharger having the features of claim 17. Modifications of the turbocharger are set forth in the sub claims 18 to 32.

According to a further aspect of the invention, the above need is met with a turbocharger having the features of claim 33.

In an exemplary embodiment of the invention, an electric motor for inserting into a center housing of a turbocharger or an electrically driven compressor, and driving a compressor wheel accommodated in a compressor housing is provided, said electric motor being supplied with electric power through at least one motor connector element, wherein at least a part of the motor connector element protrudes from a contact plane between the center housing and the compressor housing toward the side of the electric motor. Such an electric motor provides an easy and less cumbersome mountability to the turbocharger or to the electrically driven compressor. For example, the invention reduces the risk of short circuit and makes an assembly of the lead wires to the center housing less cumbersome.

According to exemplary embodiments, said part of the motor connector element may protrude to a space radially outside of the electric motor, which allows an easy attachment of a counter connector element for electric power supply without enlarging the envelope dimensions of the turbocharger.

Furthermore, the axis of said part of said motor plug connector may extend parallel to an axis of the electric motor, which allows easy assembly of the turbocharger or electrically driven device by inserting the electric motor into the center housing or a housing portion of the electrically driven device while simultaneously passing the motor connector element through an opening of the center housing or of said housing portion.

Preferably, the motor plug connector may be adapted to have a plug-in direction of a counter connector element to the part of the motor connector element in parallel to said contact plane. The motor connector element may also be adapted to have a plug-in direction of the counter connector element to the part of the motor connector element in a radial direction of the electric motor. Furthermore, the plug-in direction can be slanted with respect to the radial direction of the electric motor. The plug-in direction may further be slanted with respect to the radial direction of the electric motor about 45°. All this allows to efficiently use spaces, which are for example already existing at the peripheral regions of a turbocharger to which the electric motor may be applied, for the connection work of a counter connector element to the motor connector element. Since the plug-in direction is not parallel to the axial direction of the- motor connector element and thus not parallel to the axial direction of the turbocharger, there is no need to provide an extra space for performing the connection work by a movement in the axial direction, as an example.

According to a further exemplary embodiment, a main plane of a plug connection surface of the motor connector element may be slanted with respect to the radial direction of the electric motor. Said main plane of said plug connection surface may further extend tangentially to the electric motor. Furthermore, said main plane of the plug connection surface may be slanted about 45° with respect to the radial direction of the electric motor.

Preferably, the electric motor may further comprise a motor connector supporting member for supporting the motor connector element and electrically connecting the same to respective windings of the electric motor. This allows to easily mount the motor connector element to a housing part of the electric motor via the connector supporting member. For example, the supporting member may be made from a resin and formed like a connector block holding the motor connector elements. The supporting member may be fixed to a housing part of the electric motor or of the turbocharger by means of screws and washers or by sandwiching it between housing parts of the electric motor, or between housing parts of the electric motor and of the turbocharger. The motor connector element may also have a mismatch preventing means for preventing a mismatching connection of counter connector elements to motor connector elements. Such a mismatch preventing means allows the motor connector element to be connected exclusively to a matching counter connector element. Thus, it can be prevented that counter connector elements are connected to wrong motor connector elements, which are not supposed to be connected thereto.

Preferably, at least said part of the motor connector element may partly be covered by electrically insulating material forming said mismatch preventing means. Accordingly, only those parts of the motor connector element which are to be connected to the counter connector element may be exposed. The other parts can be electrically insulated for preventing short circuits or an electric shock to a person.

The electric motor may also be provided with six motor connector elements each for a respective one of six phase windings of the electric motor. Thus, the motor connector elements may be applied to a multiphase electric motor. Preferably, the motor connector elements are bundled in pairs or triples. Thus, the connector supporting structure can be minimized in size and the connection work can be simplified.

Furthermore, the electric motor can be accommodated in an electric motor cartridge wherein at least said part of said at least one motor connector element penetrates through the electric motor cartridge. Accordingly, the electric motor can be provided as a prefabricated structure within the electric motor cartridge which can easily be inserted into the center housing of the turbocharger or the housing of the electrically driven compressor. Simultaneously with the inserting of the cartridge into a respective housing portion, the motor connector elements can be passed through openings of the housing portion for positioning them according to the above features.

^'5 According to a further exemplary embodiment, a turbocharger has an electric motor for inserting into a center housing of the turbocharger and driving a compressor wheel accommodated in a compressor housing, said electric motor 0 being supplied with electric power through at least one motor connector element, wherein at least a part of the motor connector element protrudes from a contact plane between the center housing and the compressor housing toward the electric motor. Such a turbocharger may further 5 be embodied as described above for the electric motor. Accordingly, the above described advantages can be obtained for the turbocharger according to an aspect of the invention. 0 Other features and advantages of the invention will become apparent from the description that follows with reference being made to the enclosed drawings, in which:

Fig. 1 is a sectional view schematically showing a 5 turbocharger having a center housing provided with an electric motor accommodated in an electric motor cartridge and having a motor connector element according to an exemplary embodiment of the invention. 0 Fig. 2 is a sectional view of a part of the center housing of Fig. 1.

Fig. 3 is a sectional view schematically showing a part of the turbocharger of Fig. 1 including a part of a compressor 5 housing mounted to the center housing. Fig. 4 is a top view of the electric motor from the compressor side without an electric motor back plate.

Fig. 5 is a sectional view schematically showing the electric motor cartridge assembly and the center housing of Fig. 2 in a disassembled state.

Fig. 6 is a sectional view schematically showing a part of a turbocharger having a motor connector element according to another exemplary embodiment .

Fig. 7 is a sectional view schematically showing a part of a turbocharger having a motor connector element according to still another exemplary embodiment.

Fig. 8 is a sectional view of a turbocharger according to another configuration, and

Fig. 9 is an enlarged portion of the electrical connection according to the turbocharger shown in Fig. 8.

An electrically assisted turbocharger 1 according to the exemplary embodiment shown in Fig. 1 comprises a turbine housing 2 for accommodating a turbine wheel 3, a center housing 7 for accommodating an electric motor cartridge 4 and a compressor housing 5 for accommodating a compressor wheel 6. According to Fig. 1, the turbine housing 2 is to be disposed at the right hand side and the compressor housing 5 is to be disposed at the left hand side of the center housing 7, respectively. A shaft 8 extends through the center housing 7 and through the electric motor cartridge 4 accommodated therein, and connects the compressor wheel 6 to the turbine wheel 3. Generally, the compressor wheel 6 is driven by the turbine wheel 3 due to the exhaust gas flowing through an inlet and a volute of the turbine housing 2 thus driving the turbine wheel 3. However, when the energy content of the exhaust gas is too low to produce a required charging air pressure, the driving of the compressor wheel 6 is assisted by an electric motor 9 constituting a part of the electric motor cartridge 4, which needs electric power supply.

The electric motor 9 has a stator 10 provided with windings 27, and a rotor 11, wherein the latter may be provided in the form of the shaft 8 itself. According to this exemplary embodiment, the electric motor 9 is accommodated in the prefabricated electric motor cartridge 4, which is slid over the shaft 8 into the center housing 7 when assembling the turbocharger 1.

As can best be seen from Fig. 2, the substantially cylindrical center housing 7 has a bearing section 12 for bearing the shaft 8 (not shown in Fig. 2), and an electric motor accommodating section 13 for accommodating the electric motor cartridge 4, both sections being situated in a central portion of the center housing 7. At the left hand side, as seen in Fig. 2, the center housing 7 is provided with a compressor housing attachment section 14 for attaching the compressor housing 5 (not shown in Fig. 2) to the center housing 7.

From the fact that the diametrical dimension of the compressor housing 5 is larger than that of the electric motor 9 (see Fig. 1) results that a transition from the electric motor accommodating section 13 to the compressor housing attachment section 14 constitutes a radially extending center housing flange 15. A cylindrical center housing side wall 16 relating to the electric motor accommodating section 13 has a smaller diameter compared to the diameter of a cylindrical center housing rim wall 17 relating to the compressor housing attachment section 14. The center housing flange 15 is formed as a ring-shaped plate portion which connects the center housing side wall 16 and the center housing rim wall 17.

The center housing flange 15 is provided with openings 18 through which connector projections 32 projecting from motor connector blocks 19 (described later) of the electric motor cartridge 4 extend. Furthermore, a ring flange 20 is formed at the outer peripheral rim surface of the center housing rim wall 17 so as to enable an abutting attachment of the compressor housing 5 (see Fig. 3) which can be secured to the center housing 7 by means of bolts and threaded holes (not shown) as an example.

Furthermore, due to the above-mentioned different diameters of the center housing side wall 16 and rim wall 17, a recessed space 21 is formed, which circumferentially extends around the center housing 7 at the electric motor accommodating section 13 and thus around the electric motor 9. According to an aspect of the invention, this recessed space 21 is used for positioning the motor connector projections 32. By utilization of this space it is possible to arrange the electric connection means like the motor connector projection 32 without the need of enlarging the envelope dimensions of the turbocharger 1.

The electric motor cartridge 4 receives, amongst other things, the electric motor 9 and the motor connector blocks 19. As can best be seen from Fig. 2, the electric motor cartridge 4 is substantially cylindrical and comprises a cartridge bottom portion 22, a cartridge side wall 23, a cartridge flange 24 and a cartridge rim wall 25. The cartridge bottom portion 22 has a through hole at its center for passing through the shaft 8 and faces the turbine side of the turbocharger 1. The cartridge side wall 23 extends from the cartridge bottom portion 22 towards the compressor side of the turbocharger 1 and has a stator insert recess 26 extending over the axial length of the stator 10. Thus, when the stator 10 is received in the electric motor cartridge 4 with an edge of the stator 10 abutting against an edge of the recess 26, the windings 27 are positioned such that they do not contact the cartridge bottom portion 22. Furthermore, the compressor side end of the cartridge side wall 23 is preferably in alignment with the compressor side end of the stator 10. Thus, the compressor side of the windings 27 is located at an open space 39 defined by the cartridge flange 24 and cartridge rim wall 25, which enables an easy connection of the windings 27 to the motor connector blocks 19 (described later more in detail) .

The cartridge flange 24 radially extends from the compressor side of the cartridge side wall 23 and provides cartridge flange openings 28 which are slightly larger than the openings 18 of the center housing flange 15. The cartridge rim wall 25 extends from the radial outer end of the cartridge flange 24 towards the compressor side and is coaxial to the cartridge side wall 23. A recess 29 for receiving an electric motor plate 30 is provided at the compressor side end of the cartridge rim wall 25.

The electric motor plate 30 has a concave-shaped portion 37 towards the center thereof so as to receive a convex portion of the compressor wheel 6. The outer rim of the electric motor plate 30 fits into the recess 29 of the cartridge rim wall 25 such that the electric motor cartridge 4 with the electric motor 9 and the motor connector blocks 19 accommodated therein is closed by the electric motor plate 30. The outer rim of the electric motor plate 30, the cartridge rim wall 25 and the center housing rim wall 17 constitute a continuous annular surface which defines a contact plane 38 between the center housing 7 and the compressor housing 5, as can be seen in Fig. 3.

Two motor connector blocks 19 are provided in the electric motor cartridge 4 at opposite positions with respect to the axis A of the electric motor 9. The motor connector blocks 19 are substantially constituted by a connector base plate 31 and, in this embodiment, three connector projections 32. The connector base plate 31 is disposed at the inside of the cartridge flange 24 and the connector projections 32 extend parallel to the electric motor axis A through the openings 18 of the center housing flange 15 into the recessed space 21, as can be seen in Figures 2 and 3. The connector projections 32 are bundled in triples, as can best be seen from Fig. 4.

The connector base plate 31 is stepped such that a stepped part 33 thereof passes through the cartridge flange opening 28 and abuts against inner portions of the center housing flange 15. The connector projections 32 extend from the stepped portion 33 to the recessed space 21 while fins 34 extend from the opposite side of the base plate 31 toward the compressor side to be in alignment with the recess 29 of the cartridge rim wall 25. Thus, when the electric motor cartridge 4 is closed by the electric motor plate 30, the motor connector blocks 19 are fixed to the electric motor cartridge 4 by sandwiching the fins 34 and the connector base plate 31 between the electric motor plate 30 and the cartridge flange 24. The connector projections 32 are, as well as the fins 34, integrally formed with the connector base plate 31 from an insulating material and provide a cavity for receiving a conductive sheet plate 35. At the outside of the center housing 7, i.e. in the recessed space 21, the conductive sheet plate 35 is exposed through an opening of the connector projection 32 thus allowing to plug a counter connector element thereto. At the inside of the cartridge 4, the conductive sheet plate 35 is exposed between the fins 34 of the connector base plate 31 so as to allow the windings 27 of the electric motor 9 to be connected thereto.

The orientations of the conductive sheet plates 35 of the respective connector projections 32 are such that plug-in directions D perpendicular to respective plug connection surfaces each constituted by the corresponding conductive sheet plate 35 deviate from the radial direction RD of the turbocharger 1 (see Fig. 4) . In this embodiment, the deviation angle is about 45°. The deviation angle allows an access to the conductive sheet plates 35 of the respective connector projections 32 from the radial outer side of the turbocharger 1 while allowing a minimized positioning space of the connector projections 32 in the circumferential direction of the center housing 7.

Furthermore, the connector projections 32 of the motor connector blocks 19 are provided with mismatch preventing means 36 (see Fig. 5), also known as "Poka-Yoke-device" for preventing a mismatch connection of a counter connector element which is to be connected to the connector projection 32. In this embodiment, the mismatch preventing means 36 is provided by giving the connector projection 32 a certain plug matching shape which only matches to a corresponding plug matching shape of the pertaining counter connector element. For each pair of the connector projections/counter connector elements a different pair of plug matching shapes is provided. Thus, erroneous connecting of a counter connector element and a connector projection 32 which are not allowed to be connected to each other is prevented.

With an arrangement as described above, it is possible to easily assemble the turbocharger 1, as can be seen in Fig. 5. According to what is shown in Fig. 5, the pre-assembled electric motor cartridge 4 can be slid over the shaft 8 (not shown in Fig. 5) and inserted into the center housing 7 before mounting the compressor housing 5 (not shown in Fig. 5) . While doing so, the connector projections 32 projecting from the electric motor cartridge 4 are passed through the openings 18 of the center housing flange 15. Then, the electric motor cartridge 4 is, together with the motor back plate 30, fixed to the center housing 7 by means of screws 50 which are screwed into corresponding bores 51 in the center housing 7. Alternatively, the electric motor cartridge 4 already provided with the motor back plate 30 can be fixed to the center housing 7 by mounting the compressor housing 5 to the center housing 7 and thus clamping portions of the electric motor cartridge 4 between portions of the center housing 7 and the compressor housing 5.

The electric motor 9 of the thus assembled turbocharger 1 can now easily be connected to an electric power source via ^■ the motor connector blocks 19. The positioning of the conductive sheet plates 35 in the connector projections 32 according to an aspect of the invention allows a proper and easy connection of an electric power source to the electric motor 9 without changes of any envelope dimensions of the turbocharger being necessary. Furthermore, with such an arrangement, instead of threading the lead wires of the electric motor each through a radially extending hole in the center housing, the connector projections 32 are easily passed through the axially extending openings 18 simultaneously with the inserting of the electric motor cartridge 4 into the center housing 7. This makes the assembly easy, eliminates the presence of sharp edges which may contribute to short circuit risk and there are no lead wires which need to pass a water cavity of the center housing 7. Therefore, the water cavity is not affected by any lead wires and can be designed appropriate for a good cooling performance of the electric motor 9.

The invention is not restricted to the above described embodiment and can be changed in various modifications without departing from the scope of the invention.

For example, in the above described embodiment, the motor connector blocks 19 are fixed to the electric motor cartridge 4 by sandwiching them between the electric motor plate 30 and the cartridge flange 24 by means of the fins 34. However, the fins 34 may be omitted and the motor connector elements 19 may be fixed to the cartridge 4 by means of bolts and washers, or other fixing methods including riveting, gluing or the like.

Another modification of the motor connector block is shown in Fig. 6. According to this modification, the connector base plate 131 and the cartridge flange 124 are shaped such that the connector base plate 131 can be sandwiched between the cartridge flange 124 and the center housing flange 115. Accordingly, neither fins nor screws or washers are necessary for the fixing of the connector blocks. Furthermore, another exemplary embodiment of a turbocharger

200 according to an aspect of the invention is shown in Fig. 7. Also this turbocharger 200 comprises, among other elements, a center housing 207 which receives an electric motor 209 pre-assembled in an electric motor cartridge 202, and a compressor housing 205 which receives a compressor wheel 206. However, according to this exemplary embodiment, the motor connector block does not extend to the recessed space 21 but extends in form of a female plug connector 201 from a contact plane 238 between compressor housing 205 and center housing 207 to the inside of the electric motor cartridge 202. The female plug connector 201 provides conductivity of electricity to windings 227 of the electric motor 209. Furthermore, the compressor housing 205 is equipped with male plug connector 203 which fits to the female plug connector 201 of the electric motor cartridge 202 and to which electricity can be supplied via a main connector plug 210. When mounting the compressor housing 205 to the center housing 207, the male plug connector 203 is simultaneously plugged-into the female plug connector

201 thus providing conductivity therebetween. Accordingly, the windings 227 of the electric motor 209 can be supplied with electricity via the main plug connector 210, the male plug connector 203 and the female plug connector 201.

Claims

1. An electric motor (9) for inserting into a center housing (7) of a turbocharger (1) or an electrically driven compressor, and driving a compressor wheel (6) accommodated in a compressor housing (5), said electric motor (9) being supplied with electric power through at least one motor connector element (35) characterized in that at least a part of the motor connector element (35) protrudes from a contact plane (38) between the center housing (7) and the compressor housing (5) toward the side of the electric motor (9).

2. The electric motor (9) according to claim 1, wherein said part of the motor connector element (35) protrudes to a space radially outside of the electric motor (9).

3. The electric motor (9) according to claim 1 or 2, wherein the axis of said part of said motor plug connector (35) extends parallel to an axis (A) of the electric motor (9) .

4. The electric motor (9) according to any of claims 1 to 3, wherein the motor plug connector (35) is adapted to have a plug-in direction (D) of a counter connector element to the part of the motor connector element (35) in parallel to said contact plane (38) .

5. The electric motor (9) according to claim 4, wherein the motor connector element (35) is adapted to have a plug-in direction (D) of the counter connector element to the part of the motor connector element in a radial direction (RD) of the electric motor (9) .

6. The electric motor (9) according to claim 4, wherein the plug-in direction (D) is slanted with respect to the radial direction (RD) of the electric motor (9).

7. The electric motor (9) according to claim 6, wherein the plug-in direction (D) is slanted with respect to the radial direction (RD) of the electric motor (9) about 45°.

8. The electric motor (9) according to claim 1, 2 or 3, wherein a main plane of a plug connection surface of the motor connector element (35) is slanted with respect to the radial direction (RD) of the electric motor (9) .

9. The electric motor (9) according to claim 8, wherein said main plane of said plug connection surface extends tangentially to the electric motor (9) .

10. The electric motor (9) according to claim 8, wherein said main plane of the plug connection surface is slanted about 45° with respect to the radial direction of the electric motor (9).

11. The electric motor (9) according to any of the preceding claims, further comprising a motor connector supporting member (19) for supporting the motor connector element (35) and electrically connecting the same to respective windings (27) of the electric motor (9).

12. The electric motor (9) according to any of the preceding claims, wherein the motor connector element (35) has a mismatch preventing means (36) for preventing a mismatching connection of counter connector elements to motor connector element (35) .

13. The electric motor (9) according to claim 12, wherein at least said part of the motor connector element (35) is partly covered by electrically insulating material forming said mismatch preventing means (36) .

14. The electric motor (9) according to any of the preceding claims, having six motor connector elements (35) each for one of six phase windings (27) of the electric motor (9) .

15. The electric motor (9) according to claim 14, wherein the motor connector elements (35) are bundled in pairs or triples.

16. The electric motor (9) according to any of the preceding claims, accommodated in an electric motor cartridge (4) wherein at least said part of said at least one motor connector element (35) penetrates the electric motor cartridge (4).

17. A turbocharger (1) having an electric motor (9) for inserting into a center housing (7) of the turbocharger (1) and driving a compressor wheel (6) accommodated in a compressor housing (5), said electric motor (9) being supplied with electric power through at least one .motor connector element (35), characterized in that at least a part of the motor connector element (35) protrudes from a contact plane (38) between the center housing (7) and the compressor housing (5) toward the electric motor (9) .

18. The turbocharger (1) according to claim 17, wherein said part of the motor connector element (35) protrudes to a space radially outside of the electric motor (9).

19. The turbocharger (1) according to claim 17 or 18, wherein the axis of said part of said motor connector element (35) extends parallel to an axis of the electric motor (9) .

20. The turbocharger (1) according to claim 17, 18 or 19, wherein the motor connector element (35) is adapted to have a plug-in direction (D) of a counter connector element to the part of the motor connector element (35) in parallel to said contact plane (38).

21. The turbocharger (1) according to claim 20, wherein the motor connector element (35) is adapted to have a plug-in direction of the counter connector element to the part of the motor plug connector (35) in a radial direction (RD) of the electric motor (9) .

22. The turbocharger (1) according to claim 20, wherein the plug-in direction (D) is slanted with respect to the radial direction (RD) of the electric motor (9).

23. The turbocharger (1) according to claim 22, wherein the plug-in direction (D) is slanted with respect to the radial direction (RD) of the electric motor (9) about 45°.

24. The turbocharger (1) according to claim 17, 18 or 19, wherein a main plane of a plug connection surface of the motor connector element (35) is slanted with respect to the radial direction (RD) of the electric motor (9).

25. The turbocharger (1) according to claim 24, wherein said main plane of said plug connection surface extends tangentially to the electric motor (9) .

26. The turbocharger (1) according to claim 24, wherein said main plane of the plug connection surface is slanted about 45° with respect to the radial direction (RD) of the electric motor (9) .

27. The turbocharger (1) according to any of the preceding claims 17 to 26, further comprising a motor connector element supporting member (19) for supporting the motor connector element (35) and electrically connecting the same to respective windings (27) of the electric motor (9).

28. The turbocharger (1) according to any of the preceding claims 17 to 27, wherein the motor connector element (35) has a mismatch preventing means (36) for preventing a mismatching connection of counter connector elements to motor plug connector elements (35) .

29. The turbocharger (1) according to claim 28, wherein at least said part of the motor connector element (35) is partly covered by electrically insulating material forming said mismatch preventing means (36) .

30. The turbocharger (1) according to any of the preceding claims 17 to 29, having six motor connector elements (35) each for one of six phase windings (27) of the electric motor (9) .

31. The turbocharger (1) according to claim 30, wherein the motor connector elements (35) are bundled in pairs or triples.

32. The turbocharger (1) according to any of the preceding claims 17 to 31, wherein the electric motor (9) is accommodated in an electric motor cartridge (4), wherein at least said part of said at least one motor connector element (35) penetrates the electric motor cartridge (4)

33. A turbocharger (1) having an electric motor (9) according to any of claims 1 to 16.