EP3785351A1

EP3785351A1 - Electric motor and method for producing same

Info

Publication number: EP3785351A1
Application number: EP19721977.7A
Authority: EP
Inventors: Peter Schwanemann; Andreas KESKINOGLU
Original assignee: Schaeffler Technologies AG and Co KG
Current assignee: Schaeffler Technologies AG and Co KG
Priority date: 2018-04-27
Filing date: 2019-04-23
Publication date: 2021-03-03
Also published as: CN112020814A; DE112019002187A5; US20210143704A1; DE102018110176A1; WO2019206380A1

Abstract

The invention relates to an electric motor (1) comprising a cylindrical housing (10), a stator (2) which consists of multiple stacked metal sheets (3) and is mounted in the housing (10), and a rotor (4) which sits on a shaft (6) that is rotatably mounted in a respective bearing shield (7) provided at a first end (11) or a second end (12) of the housing (10). The housing (10) is die-cast, and the stator (2) protrudes seamlessly into a wall (9) of the housing (10) to a depth (T) which is less than the thickness (W) of the wall (9). The invention also relates to a method for producing such an electric motor (1).

Description

ELECTRIC MOTOR AND METHOD FOR THE PRODUCTION THEREOF

The invention relates to an electric motor. The invention particularly relates to an electric motor with a cylindrical housing, a stator which consists of a plurality of stacked sheets and which is supported in the housing, and having a rotor which sits on a shaft which in each case a bearing plate, which at a first end or is provided at a second end of the housing, is rotatably mounted.

Furthermore, the invention relates to a method for producing such an electric motor.

Various housing manufacturing and assembly concepts for electric motors are known and are already used in series.

German Offenlegungsschrift DE10 201 1076904 A1 discloses a cooled stator for an electric motor.

German Offenlegungsschrift DE 10 201 1 082 461 A1 discloses a stator housing for an electric motor.

European Patent Application EP 2 933 902 A1 discloses a heat dissipation of an electric machine.

The German patent application DE 10 2015 200 096 A1 discloses a

Cooling jacket arrangement for an electric motor.

The German patent application DE 198 51 439 A1 discloses an electrical

Machine with a stator and a die-cast housing. Cooling channels are integrated in the stator. German patent application DE 10 2009 000 591 A1 discloses a

Drive device, preferably hybrid drive device, in particular for a motor vehicle. An internal combustion engine is provided for driving the motor vehicle. In a housing, an electric machine with a stator and a rotor is arranged. The housing is provided with at least one cooling fin to improve the cooling of the electrical machine.

German Offenlegungsschrift DE 10 2012 213 237 A1 discloses an electrical machine with a housing, a stator and a rotor. A cooling channel is provided between the housing and the stator. The housing and the stator are positively connected to each other via axial webs against radial rotation, wherein the webs are designed to redirect the cooling medium.

From the prior art, the structure of a housing of three components is known. The first component is a so-called A-end shield, the second component is a

cylindrical middle housing part as an extruded profile and the third component is also a bearing plate, a so-called B-end shield. The A-end shield is on the output side and usually carries a fixed bearing. The B-end shield is arranged on the axially opposite side and the storage takes place, for example, without limitation, via a sliding seat to compensate for thermal expansion of the armature of the rotor can. End shields are usually used in electric machines the rear and front covers of the housing, which oppose the machine interior

Protect the contact and take up the bearings of the shaft ends of the armature of the rotor. A disadvantage of this three-part structure of the housing is that the stator is adjacent only from the outside to the cylindrical central housing part or stator and housing are arranged only adjacent to each other (see Fig. 1). These

Arrangement of stator and housing causes a relatively poor security against rotation and stability. To achieve better stability, the housing must be made of three components larger, as stated below. In order to ensure against rotation in this arrangement of stator and housing, a high contact pressure (for example by shrink fit, press fit or the like) is required. To the housing stability at this contact pressure and thus To ensure connected mechanical stresses, the thickness of the

Housing therefore be made relatively large, making the case heavier and more expensive to manufacture, which in turn meets today's requirements

Compactness and price sensitivity contradict. In addition, there is a relatively poor thermal transition between the stator and the housing.

The object of the invention is therefore to provide an electric motor that is compact, inexpensive and easy to manufacture and assemble and also safe in operation.

This object is achieved by an electric motor according to claim 1. The

Subclaims contain advantageous embodiments of the electric motor.

The object of the invention is also to provide a method for producing an electric motor, which produces a compact electric motor inexpensively and in a simple manner, wherein the electric motor is easy to assemble and also safe to operate.

This object is achieved by a method for producing an electric motor according to claim 6. The subclaims contain advantageous embodiments of the method.

In one embodiment, the electric motor according to the invention comprises

cylindrical housing, a stator and a rotor. The stator comprises a plurality of stacked sheets or consists of a plurality of stacked sheets, and the stator is supported in the housing. The rotor sits on a shaft. The shaft is rotatably mounted, for example, in each case a bearing plate, which closes the housing. The respective end shield is provided at a first end or at a second end of the housing. According to the invention, at least the housing (housing shell) is pressure-cast. In addition, according to the invention, the stator protrudes with a depth seamlessly into a wall of the housing, wherein the depth is smaller than a thickness of the wall. The

Housing is thus directly, seamlessly and firmly on the stator and encloses the stator even to the said depth, which has several advantages. First, it is so designed electric motor compact. Second, the stator is safe and firm, especially against rotation, on or even in part

Housing anchored so that the electric motor is safe in operation. Third, this achieves a very good heat transfer resistance. Fourth, die casting is a low cost manufacturing process. Fifth, the assembly of the

Electric motor itself and in his environment easy.

In one embodiment of the electric motor according to the invention, the housing made of aluminum is pressure-cast, which also has a cost effect on the production of the electric motor and also reduces the weight of the electric motor.

In one embodiment of the electric motor according to the invention, at least a part of the stacked sheets of the stator has a plurality of teeth on an outer circumference

formed, which protrude into the wall of the die-cast housing. This too has several advantages. The teeth ensure an even better anchoring of the

Statorblechpakets in the housing, the weight of the electric motor is thereby further reduced and in small spaces can thereby be provided space for cooling channels for a cooling medium in the housing. The recesses for the cooling channels, for example, expediently, but not necessarily, below the

Statorzähne be formed in the wall of the housing. The shape of the teeth on the outer circumference should be chosen accordingly so that a sufficient

Anchoring is given, for example, but without limitation of the invention, as a hook with at least one barb, but also as a simpler formed rectangles, trapezoids or triangles, optionally with rounded corners, such as in a toothing on known gears.

In one embodiment of the electric motor according to the invention a plurality of channels for a cooling medium in the wall of the housing are formed. The cooling medium may be, for example, a mixture of water and glycol. The channels serve the effective dissipation of heat loss of the electric motor and can in one

Embodiment be formed directly in the die casting. In further

Embodiments, the channels are formed in an axial direction and analogous to Housings with an extruded profile component connected via the two end shields.

In one embodiment of the electric motor according to the invention, the cylindrical housing is integrally connected to a bearing plate at the first end or at the second end of the housing. The die-cast housing is then poured, for example, in a "pot shape", that is, a first bearing plate is cast directly to the statortragenden housing part and materially connected thereto and only one additional, so a second bearing plate are mounted to the housing got to. Again, the execution of integrated cooling channels is conceivable.

The pot shape also allows the production of a combined housing, which has already been formed for example on the housing structures for the cultivation of a transmission.

In one embodiment of the electric motor according to the invention a plurality of channels are formed in the bearing plate, which are fluidly connected to the channels in the wall of the housing for circulation of the cooling medium. These channels in the end plate also serve to effectively dissipate heat loss from the electric motor.

The inventive method for producing an electric motor comprises several steps. First, the electric motor in turn comprises a cylindrical housing, a stator which comprises a plurality of stacked sheets or consists of several stacked sheets, wherein the stator is mounted in the housing, and a rotor which sits on a shaft which in each case a bearing plate, the a first end

or is provided at a second end of the housing. In a first step, the stator stacked from a plurality of laminations is so into one

Die casting mold introduced that the stator partly into a free space of the

Die casting mold protrudes. In a next step, the free space of the die is ejected with a good heat-conducting material, so that the heat-conducting material fits seamlessly against the part of the stator projecting into the free space and forms the housing which supports the stator. The advantages of the method according to the invention are already described in connection with the electric motor according to the invention. In one embodiment of the method, the stator winding with insulation in a later manufacturing step after the ejection of the free space of the

Die casting mold with a good heat conducting material introduced.

In one embodiment of the method according to the invention, a plurality of teeth are formed on an outer circumference on some of the stacked sheets of the stator in the stator used in the die casting mold. The teeth are overmolded by the material as the die is ejected so that the teeth protrude into a wall of the die-cast housing. Possible shapes and the advantages of the teeth are already described in connection with the electric motor according to the invention.

In one embodiment of the method according to the invention, several channels for a cooling medium are formed in the wall of the housing during the ejection of the free space of the die-casting mold. The advantages of the channels are already described in connection with the electric motor according to the invention.

In one embodiment of the method according to the invention is in each case a

End shield set to the first end and the second end of the housing such that the multiple channels of the housing communicate with several channels in the respective bearing plate for the circulation of the cooling fluid. The advantages of the bearing plates and channels are already described in connection with the electric motor according to the invention.

In one embodiment of the method according to the invention, the die casting mold is designed such that in addition to the housing, a bearing plate at the first end or second end of the housing is formed such that the bearing plate

cohesively connected to the housing and formed in the bearing plate several channels are fluidly connected to the channels in the wall of the housing for circulation of the cooling medium. The benefits are also already in the

Connection described with the electric motor according to the invention. The invention finds application, for example, but without limitation of the invention, in all devices in which rotating electrical machines are installed. In particular, but not exclusively, the invention may be used in the field of electric drive systems of e-axis and hybrid systems.

In addition, the invention and its advantages with reference to the attached

Drawings explained in more detail.

Fig. 1 shows a sectional view of an electric motor of the prior art.

2 shows an enlarged partial view of an embodiment of the mounting method of the stator according to the invention in the housing of an embodiment of the invention

electric motor according to the invention.

3 shows a sectional view through the housing and the stator along a sectional plane A-A perpendicular to the axis of an embodiment of the electric motor.

4 shows a sectional view through the housing and the stator along a section plane B-B running radially to the axis of the electric motor according to FIG. 3.

Fig. 5 shows a sectional view through the housing along another, perpendicular to the axis of the electric motor of Fig. 3 sectional plane A-A, which is outside the range of the stator.

Fig. 6 shows a sectional view through the housing and the stator along another, to the axis of the electric motor of FIG. 3 radially extending cutting plane B- B.

Fig. 7 shows a partial view of an embodiment according to the invention, in which a bearing plate is an integral part of the housing. Fig. 8 shows a plan view of a part of a sheet for a sheet stack of the stator.

9 shows a schematic partial view of an embodiment of a die-casting mold for producing at least one housing.

10 shows a schematic partial view of a stator inserted into the die casting mold.

Fig. 1 1 shows a schematic partial view of a material injected into the die.

Fig. 12 shows a schematic partial view of the removed from the die casting housing with the stator.

The drawings are merely specific embodiments of the invention. However, the invention should not be expressly limited to the embodiments shown.

Fig. 1 shows a sectional view of an electric motor 1 of the prior art. The electric motor 1 comprises a cylindrical housing 10, a stator 2 and a rotor 4. The stator 2 consists of a plurality of stacked sheets 3 (see the sheets 3 in detail in Fig. 2) and is supported in the housing 10. The rotor 4 is seated on a shaft 6 through whose center the axis A (axis of rotation) of the electric motor 1 runs. The shaft 6 is in one embodiment, and as shown in Fig. 1, rotatably mounted in each case a bearing plate 7. In this case, a first bearing plate 7 is provided at a first end 1 1 of the housing 10 and a second bearing plate 7 is provided at a second end 12 of the housing 10. The respective end shield 7 constitutes a cover and closes off the housing 10, as already described in detail in the introduction. As shown in Fig. 1, a certain distance is usually provided in the prior art between the stator 2 and the housing 10, so that the stator 2 is not directly connected to the housing 10, or the stator 2 is adjacent only from the outside to the cylindrical central housing part or stator 2 and housing 10 are only adjacent to each other. As already described in the introduction, it is disadvantageous in this design that the electric motor 1 constructed in this way is not compact and therefore expensive to produce; the stator 2 may not be securely and firmly anchored to the housing 10, in particular not twist-proof. so that the electric motor 1 may not be safe in operation, and moreover, between the stator 2 and the housing 10 is a relatively poorer thermal

Transition given.

Fig. 2 shows an enlarged partial view of an embodiment of the mounting method according to the invention of the stator 2 in the housing 10 of an embodiment of the

Electric motor according to the invention 1. Again, the inventive

Electric motor 1, a cylindrical housing 10, a stator 2 and a rotor 4. The stator 2 is composed of a plurality of stacked sheets 3 and is supported in the housing 10. The rotor 4 is seated on a shaft 6 through whose center the axis A (axis of rotation) of the electric motor 1 runs. The shaft 6 is in one embodiment, and as shown in Fig. 1, rotatably mounted in each case a bearing plate 7. In this case, a first bearing plate 7 is provided at a first end 1 1 of the housing 10 and a second bearing plate 7 is provided at a second end 12 of the housing 10. The respective end shield 7 closes off the housing 10.

According to the invention and in contrast to Fig. 1, however, in Fig. 2, the housing 10 is die-cast and the stator 2 projects with a depth T seamlessly into a wall 9 of the housing 10. The depth T is smaller than a thickness W of the wall. 9 The stator 2 is thus radially surrounded by the molded die-cast housing 10 and the housing 10 carries the stator 2. As already explained above, the stator 2 is then directly, seamlessly and firmly on and even at least partially in the housing 10, which has several advantages Has. The thus constructed electric motor 1 is compact and therefore inexpensive to manufacture; the stator 2 is thereby securely and firmly, in particular also against rotation, anchored on or in the housing 10, so that the electric motor 1 is safe in operation; a very good heat transfer resistance reached; Die casting is a low cost manufacturing process; and the assembly of the electric motor 1 itself and in its environment is simple.

In one embodiment of the electric motor 1 according to the invention, the housing 10 is pressure-cast from aluminum, which also has a cost-effective effect on the production and weight of the electric motor 1.

FIG. 3 shows a sectional view through the housing 10 and the stator 2 along a sectional plane A-A according to FIG. 4 that is perpendicular to the axis A of an embodiment of the electric motor 1, the sectional plane A-A lying within the area of the stator 2. The axis A is shown here as a point, since the axis A comes out of the plane in this sectional view, so to speak.

In the embodiment of the electric motor 1 according to the invention shown in Fig. 3 are a plurality of channels 15 for a cooling medium in the wall 9 of the housing 10th

educated. The cooling medium may be, for example, a mixture of water and glycol. The channels 15 serve the effective dissipation of heat loss of the electric motor 1 and can be formed directly in an embodiment in die casting. The recesses for the cooling channels 15 are in the illustration of FIG. 3 expediently, but not necessarily formed below the stator teeth 24 in the wall 9 of the housing 10. The other components of the electric motor 1 are described in connection with FIG. 2.

In the embodiment of the electric motor 1 according to the invention shown in Fig. 3, at least a portion of the stacked sheets 3 of the stator 2 on the outer circumference 13 has a plurality of teeth 14 which project into the wall 9 of the die-cast housing 10. The shape of the teeth 14 on the outer circumference should be chosen to provide sufficient anchorage, for example but not limited to the invention, as relatively complex hooks with two barbs each, but also as simply shaped rectangles, trapezoids or triangles such as

For example, a toothing on known gears. In the illustration after For example, but not limited to the invention, the teeth 14 are formed as elongated, rounded trapezoids.

4 shows a sectional view through the housing 10 and the stator 2 along a sectional plane BB according to FIG. 3 extending radially to the axis A of the electric motor 1 according to FIG. 3. In the illustrated embodiment, the channels 15 are in an axial direction, ie parallel to the axis A, shaped and analogous to housings with an extruded profile component on the two end shields 7 (see, for example, Fig. 7) connected. It can be clearly seen that the stator 2 of the die-cast housing 10 with a depth T projects seamlessly into a wall 9 of the housing 10 and the depth T is smaller than a thickness W of the wall 9. The stator 2 is thus surrounded radially by the molded die-cast housing 10 and the housing 10 carries the stator 2. As explained above, the stator 2 is thus directly, seamlessly and firmly on or even partially in the housing 10. The other components of the electric motor 1 are described in connection with FIGS. 2 and 3.

FIG. 5 shows a sectional view through the housing 10 along a sectional plane AA according to FIG. 6 which is also perpendicular to the axis A of the electric motor 1 according to FIG. 3, the sectional plane AA (in contrast to FIG and 4) is outside the range of the stator 2. Accordingly, the stator 2 is shown in Fig. 5 only schematically (dashed lines). The other components of the

Electric motors 1 are described in connection with FIGS. 2 to 4.

FIG. 6 shows a sectional view through the housing 10 and the stator 2 along a sectional plane BB according to FIG. 5 which is also radially opposite to the axis A of the electric motor 1 according to FIG. 4 along other lines of the electric motor 1 are described in connection with FIGS. 2 to 5. Again, it can be clearly seen that the stator 2 projects into the housing 10 with a depth T that is significantly smaller than the wall thickness W of the wall 9 of the housing 10.

Fig. 7 shows a partial view of an embodiment of the invention

Electric motor 1, in which a bearing plate 7 is an integral part of the housing 10. The cylindrical housing 10 is integrally connected to a bearing plate 7 at the first end 11 and / or at the second end 12 of the housing 10, wherein here, without limiting the invention, only the bearing plate 7 at the first end 1 1 is shown. The other end shield 7 (not shown in FIG. 7) is attached to the housing 10

axially symmetrical with respect to a vertical axis A to the first bearing plate 7 mounted and the two end shields 7 then each form a cover for the housing 10. The structure of the housing 10 of FIG. 7 is thus of three parts: A-end shield, cylindrical middle housing part Extruded profile and B-end shield.

The die-cast housing 10 is cast, for example in a "pot shape", that is, that the first bearing plate 7 is molded directly to the stator 2 supporting part of the housing 10 and only one additional, so the second,

End plate 7 is necessary (not shown in Fig. 7), which must be mounted on the housing 10. Here, too, the execution of integrated cooling channels 16 in the respective bearing plate 7 is conceivable, as shown in Fig. 7.

In the illustrated embodiment of FIG. 7, the plurality of channels 16 molded in the housing 10 die-cast with the housing 10 are fluidly connected to the channels 15 in the wall 9 of the housing 10 for circulating the cooling medium. These channels 16 in the cast-on end shield 7 serve the effective dissipation of heat loss of the electric motor 1. The other, not shown bearing plate can be provided with cooling channels.

FIG. 8 shows a plan view of a part of a sheet 3 for a sheet stack of the stator 2. As shown in FIG. 3, in the embodiment of the invention

Electric motor 1 of FIG. 8, at least a portion of the stacked sheets 3 of the stator 2 on an outer periphery 13 of the respective sheet 3, a plurality of teeth 14 are formed, which protrude into the wall 9 of the die-cast housing 10. This also has several advantages, as already explained above. The teeth 14 provide an even better

Anchoring of the stator lamination in the housing 10, the weight of the electric motor 1 is thereby further reduced and in small installation spaces can thereby space for cooling channels 15 (see Fig. 3 to 7) provided for a cooling medium in the housing 10 become. The shape of the teeth on the outer circumference 13 should be chosen accordingly so that a sufficient anchorage is given, for example and as shown in Fig. 8, but without limitation of the invention, as a hook with each

at least one barb 17, wherein in each case two barbs 17 per tooth 14 are shown. However, the hook shape of the teeth 14 selected in FIG. 8 is complex and therefore expensive to manufacture. As already described above, other, simpler shapes for the teeth can be chosen instead, for example, without limitation of the invention, rectangles, trapezoids (see Fig. 3) or triangles, optionally with rounded corners, such as in a toothing on known gears ,

The recesses for the cooling channels 15 may, for example, expediently, but not necessarily, be formed below the stator teeth 24 (see FIG. 3) in the wall 9 of the housing 10.

9 shows a schematic partial view of an embodiment of a die-casting mold 20 for producing at least one housing 10 for the electric motor 1 according to the invention. As shown in the schematic partial view of FIG. 10, according to the inventive method for producing the electric motor 1, the first of several Sheet 3 stacked stator 2 is inserted into the die 20 in such a way that the stator 2 projects partly into a free space 22 of the die 20. As shown in the schematic partial view of FIG. 11, the free space 22 of the die casting mold 20 is subsequently sprayed with a good heat-conducting material 30, so that the heat-conducting material 30 fits seamlessly against the part of the stator 2 projecting into the free space 22 and the die-cast housing 10 forms, which holds the stator 2. Subsequently, the die 20 can be removed from the housing 10. The schematic partial view of Fig. 12 shows the removed from the die 20 housing 10 with the stator 2. The stator 2 projects with a depth T seamlessly into a wall 9 of the housing 10. The depth T is smaller than a thickness W of the wall 9. The stator 2 is thus surrounded radially by the molded and die-cast housing 10 and the housing 10 carries the stator 2. The advantages of the invention Method are already described in connection with the electric motor 1 according to the invention.

In one embodiment of the method, the winding of the stator 2 with

Insulations in a later manufacturing step after the ejection of the free space 22 of the die 20 with a good heat conducting material 30 (see FIG. 11) introduced.

In one embodiment of the method according to the invention, in the stator 2 inserted into the die, several teeth 14 are formed on some of the stacked sheets 3 of the stator 2 on an outer periphery 13 (not shown in FIGS. 9 to 12, see FIG. 8 instead). The teeth 14 are overmolded by the material 30 during the ejection of the die casting mold 20 according to FIG. 11, so that the teeth 14 protrude into the wall 9 of the die-cast housing 10. The advantages of the teeth 14 have already been described in connection with FIGS. 3 and 8.

In one embodiment of the method according to the invention, several channels 15 for a cooling medium are formed in the wall 9 of the housing 10 during ejection of the free space 22 of the die casting 20 (as shown in FIG. 11) (not shown in FIGS. 9 to 12, see FIG. 3 instead) to 7). The advantages of the channels 15 have already been described above.

In one embodiment of the method according to the invention is in each case a

End plate 7 on the first end 1 1 and the second end 12 of the

Housing 10 is set such that the plurality of channels 15 of the housing 10 with several channels 16 in the respective bearing plate 7 for the circulation of the cooling fluid communicate fluidly (not shown in Fig. 9 to 12, see instead Fig. 7). The advantages of the bearing plates 7 and channels 15, 16 are already described above.

In one embodiment of the method according to the invention, the die casting mold 20 is designed such that in addition to the housing 10, a bearing plate 7 at the first end 1 1 or second end 12 of the housing 10 is formed such that the Bearing plate 7 is materially connected to the housing 10 and formed in the bearing plate 7 a plurality of channels 16 are fluidly connected to the channels 15 in the wall 9 of the housing 10 for circulation of the cooling medium, which is also not shown in Fig. 9 to 12, but instead see Fig. 7). The advantages are also already described above.

LIST OF REFERENCE NUMBERS

1 electric motor

2 stators

3 sheet metal

4 rotor

6 wave

7 end shield

9 wall

10 housing

1 1 first end

12 second end

13 outer circumference

14 tooth

15 channel

16 channel

17 barbs

20 die casting mold

22 free space

24 stator tooth

30 material

A axis

A-A cutting plane

B-B cutting plane

T depth

W wall thickness

Claims

claims

1. Electric motor (1) comprising

a cylindrical housing (10),

a stator (2) consisting of a plurality of stacked sheets (3) and supported in the housing (10),

a rotor (4) seated on a shaft (6) in each case one

Bearing plate (7) which is provided at a first end (1 1) or at a second end (12) of the housing (10) is rotatably mounted,

characterized in that

the housing (10) is die-cast and the stator (2) projects with a depth (T) seamlessly into a wall (9) of the housing (10), the depth (T) being less than a thickness (W) of the wall (9 ).

2. Electric motor (1) according to claim 1, wherein at least a part of the stacked

Sheet metal (3) of the stator (2) on an outer circumference (13) has a plurality of teeth (14) formed, which protrude into the wall (9) of the die-cast housing (10).

3. Electric motor (1) according to one of the preceding claims, wherein a plurality of channels (15) for a cooling medium in the wall (9) of the housing (10) are formed.

4. Electric motor (1) according to one of the preceding claims, wherein the

cylindrical housing (10) with a bearing plate (7) at the first end (1 1) or at the second end (12) of the housing (10) is integrally connected.

5. Electric motor (1) according to claim 4, wherein in the bearing plate (7) a plurality of channels (16) are formed, which are fluidly connected to the channels (15) in the wall (9) of the housing (10) for circulation of the cooling medium.

6. A method for producing an electric motor (1), wherein the electric motor (1) has a cylindrical housing (10), a stator (2), which is stacked from a plurality Sheet metal (3) and is in the housing (10) is supported, and a rotor (4) which sits on a shaft (6), in each case a bearing plate (7) at a first end (1 1) or at a second end (12) of the housing (10) is provided comprises;

characterized by the following steps:

Inserting the stator (2) stacked of a plurality of sheets (3) into a die-casting mold (20) such that the stator (2) protrudes partly into a free space (22) of the die-casting mold (20); and

Ejecting the clearance (22) of the die (20) with a good heat conducting material (30) so that the heat conducting material (30) abuts seamlessly on the part of the stator (2) projecting into the clearance (22) and the housing (10 ) which supports the stator (2).

7. The method of claim 6, wherein in the die-casting mold (20)

The stator (2) used on some of the stacked sheets (3) of the stator (2) on an outer circumference (13) a plurality of teeth (14) are formed, which are overmolded during ejection of the die casting mold (20) of the material (30) the teeth (14) protrude into a wall (9) of the die-cast housing (10).

8. The method according to any one of claims 6 to 7, wherein during the ejection of the

Freiraums (22) of the die casting mold (20) a plurality of channels (15) for a cooling medium in the wall (9) of the housing (10) are formed.

9. The method of claim 8, wherein in each case a bearing plate (7) on the first end (1 1) or the second end (12) of the housing (10) is set such that the plurality of channels (15) of the housing (10). with a plurality of channels (16) in the respective bearing plate (7) for the circulation of the cooling fluid communicate fluidly.

10. The method according to any one of claims 8 to 9, wherein the die-casting mold (20) is designed such that in addition to the housing (10) has a bearing plate (7) on first end (1 1) or second end (12) of the housing (10) is formed such that the bearing plate (7) is integrally connected to the housing (10) and in the bearing plate (7) formed several channels (16) the channels (15) in the wall (9) of the housing (10) are fluidly connected to the circulation of the cooling medium.