WO2007107131A1

WO2007107131A1 - Stator for an electric motor and method for the production thereof

Info

Publication number: WO2007107131A1
Application number: PCT/DE2006/002309
Authority: WO
Inventors: Michael Bulatow
Original assignee: Temic Automotive Electric Motors Gmbh
Priority date: 2006-03-20
Filing date: 2006-12-22
Publication date: 2007-09-27
Also published as: DE112006003573A5

Abstract

The invention relates to a stator (1) for an electric motor. Said stator has a stator core (3), which is surrounded by a housing (6) and whose surface (2.1, 3.1) that faces the housing inner wall (6.1) is provided with at least one depression (2.2), the outer edge (2.3) of which engages with the housing inner wall (6.1).

Description

Description. STATOR FOR AN ELECTRIC MOTOR AND METHOD FOR THE PRODUCTION THEREOF

The invention relates to a stator for an electric motor _^ and a method for manufacturing such a stator.

Such stators are particularly suitable for use in motor vehicles. In the motor vehicle sector, electric motors, which are designed as small motors, play an important role due to the limited installation space. Small engines are electric motors with small dimensions and usually have. a power up to 1 kW.

Electric motors can be designed as internal rotor or external rotor motors. Internal rotor motors have an outer stator and an inner rotor. The rotor is inserted coaxially in the stator. In an external rotor motor, the outer rotor coaxially surrounds the inner stator. The rotor or the rotor shaft is rotatably mounted in all variants.

Stators are known in the art, which are composed of Statorpolzähnen. The stator pole teeth are preferably coupled together. For this purpose, the

Statorpolzahne either externally provided with thin webs or manufactured with hinges. Such a constructed stator can be opened. The Statorpolzahne preferably remain coupled. In the unfolded state, the stator can be easily handled. Also can with low

Effort and high density electrical windings are applied. After winding, the stator pole teeth are collapsed into the closed cylindrical shape of the stator. Alternatively, the stator may be formed in one piece and have outwardly any shape and be round inside and thus cylindrical. In order to prevent the outer stator, which is surrounded by an outer housing, from rotating in the case of an internal rotor motor, it is usually materially or mechanically joined in a housing. When integrally joining the stator is glued into the housing or molded with plastic. Such a joining process is particularly complicated and expensive. During mechanical joining, the stator is caulked to the housing. In an alternative method, the housing is heated during insertion of the stator. By subsequent cooling, the housing shrinks, so that the stator is mechanically held in the housing. This process is expensive.

The invention is therefore based on the object to provide a stator for an electric motor and a method for producing such a, whereby a simple construction of an electric motor with the greatest possible protection against spin is made possible.

According to the invention the object is achieved by a stator having the features specified in claim 1, and by a method having the features specified in claim 11.

Advantageous embodiments of the invention are the subject of the dependent claims.

The stator according to the invention for a, in particular designed as an internal rotor motor electric motor has a stator, which is surrounded by a housing. The stator, in particular a laminated core is according to the invention provided on its outwardly, in particular to the housing inner wall facing surface with at least one recess, wherein a resulting outer edge engages in the surrounding housing inner wall. The depression may in particular be designed as a groove introduced into the surface. In this case, the recess is preferably made sharp-edged on the upper edge, which forms the outer edge, so that this in the housing inner wall when mounting cuts. Alternatively, the upper edge may be slightly rounded. The shape of the outer edge depends in particular on the nature of the housing material. The outer edge preferably engages positively and non-positively in the inner wall of the housing.

This leads to a particularly secure anti-rotation. In addition, a very stable connection of stator and housing is possible with little effort.

In one possible embodiment, the recess of the stator core has a substantially radially outwardly extending edge. In other words, at least the upper edge of the outer edge forms the surface of the stator packet adjacent to the housing inner wall. In this case, the outer edge on the surface parallel to the rotor shaft and along the longitudinal axis of the stator core.

In a preferred embodiment, the outer edge is in the form of a barb. As a result, a secure intervention, in particular cutting into the housing inner wall is made possible. In addition, this allows a particularly stable connection between the stator and the housing.

Conveniently, at least two outer edges are introduced at a predetermined distance from each other in the surface stator. The distance between the outer edges corresponds to the width of the recess, in particular the width of the groove. In this case, the distance between the two outer edges can vary, for example, to reduce the surface pressure. In one possible embodiment, the two spaced-apart outer edges of the recess are in the form of a respective barb. Depending on the type and shape of the stator, z. B. stator or stator of single Statorpolzahnen or a stator of a Stator- polzahnscharnierkette, the shape and number of wells and the shape and number of edges vary. For example, in a stator of Statorpolzahnen ever Statorpolzahn and depending on the shape of the recess be introduced one or two edges in the form of barbs in the surface of the respective Statorpolzahns. If only one edge in the form of a barb inserted per Statorpolzahn, the edges of adjacent Statorpolzähne are mirrored to each other or rotated by 180 °. This allows safe protection against spinning in both directions.

In an additional or alternative embodiment, the outer edge may also be provided with a radially outward elevation. The survey engages like a spine in the housing inner wall.

Depending on the embodiment of the stator, the housing may be made of metal or another suitable material, for. As plastic, be formed.

In the method according to the invention for producing a stator with a stator core and a housing surrounding it, at least one depression is introduced into the surface of the stator core facing the inner wall of the housing, at least one outer edge of which is pressed into the inner wall of the housing when the cylindrical stator core is inserted , In this case, the recess may be formed in particular as a sharp-edged groove. Alternatively, the edge may be slightly rounded with a rounding edge of about 0.3 mm. The shape of the edge and the Kantengrat depend, for example, on the nature of the method of introducing the depression. Thus, when inserting the recess z. B. achieved by lasers, for example, patterned parts no sharp, but a slightly rounded edge. By pressing the sharp or round-edged recess of the stator in the housing inner wall when joining the housing and stator, the housing is partially positively and non-positively joined in the recess of the stator, so that a stable connection between the housing and stator is possible. When inserting the stator pack into the housing For example, the housing with little effort on the collapsed or one-piece Stätorpaket and thus the hollow cylindrical housing inner wall added to the cylindrical ^' stator or vice versa, then the stator is pressed into the housing. In addition, the housing can be one or more parts, z. B. half-shell, be formed. Also, a multi-part housing made of different materials, eg. As aluminum-plastic housing, aluminum-steel housing, be formed. Conveniently, bonding is performed on the surface of the stator core or on the surface of a single stator pole tooth or on the surface of a plurality of stator pole teeth. The connection between stator and housing can be made with high precision and stability.

The advantages achieved by the invention are, in particular, that with little effort, a stator for an electric motor can be produced with a particularly good spin-through protection.

Also claimed is an electric motor with a stator according to the invention.

An embodiment of the invention will be explained in more detail with reference to drawings. Show:

1 schematically in cross section a stator in the folded and joined state with a plurality of stator pole teeth, which engage in a housing inner wall of a surrounding housing,

Fig. 2 shows schematically a single Statorpolzahn in

Cross-section with a recess made in the outwardly directed surface, 3 schematically shows an alternative embodiment for a single Statorpolzahn with an outward protrusion,

Fig. 4 shows schematically an alternative embodiment for a one-piece stator, and

Fig. 5 and 6 schematically another alternative embodiment for a multi-part stator with a per Statorpolzahn introduced individual

Outer edge, which engages in the surrounding housing inner wall.

Corresponding parts are provided in all figures with the same reference numerals.

FIG. 1 schematically shows, in cross-section, an exemplary embodiment of a stator 1 made of stator pole teeth 2 in the folded-up state. In this case, a plurality of the stator 1 forming, in particular T-shaped Statorpolzähne 2 by one

Rotor shaft 4 is arranged. In a manner not shown in detail and ^' way is the stator 1, in particular each Statorpolzahn 2 along the longitudinal axis of the stator 1 of a plurality of identical individual sheets, which are stacked identically to each other to a stator 3 and then joined together materially assembled. The substantially T-shaped Statorpolzahne 2, for example, by means of a film hinge, not shown, or in any other suitable manner coupled to each other flexibly hinged. Each Statorpolzahn 2 can in a suitable manner, for example, from painted or linked individual sheets, which are stacked identical to each other in the longitudinal axis of the stator 3, assembled and in particular stanzpaketiert or stoeffschlüssig connected, z. B. glued be.

The stator 1 ^has' in the collapsed state is substantially a hollow cylindrical shape. In addition, the Stator 1 surrounded by a housing 6. The housing 6 is for example a metal housing, for. As aluminum, steel o- a plastic housing. In order to secure the stator 6 against spinning, the surface 3.1 of the stator packet 3 and thus the surface 2.1 of the stator pole tooth 2 engages in the assembled state of the stator 1 in the housing inner wall 6.1 of the surrounding housing 6.

FIG. 2 shows in detail a single stator pole tooth 2. For a positive and non-positive engagement of the surface 2.1 of the respective stator pole tooth 2 in the housing inner wall 6.1, a recess 2.2 is made in the surface 2.1 pointing outwards in the direction of the housing inner wall 6.1. The depression 2.2 is at least partially sharp-edged. For example, the recess

2.2 a substantially radially extending outer edge 2.3, which extends substantially parallel to the rotor shaft 4 and along this over the entire length of the surface 2.1 of the stator 3. For a secure engagement of the sharp-edged depression 2.2 in the housing inner wall 6.1, the outer edge 2.3 is formed in the form of a barb. Any other suitable form is also possible.

In addition, the surface 2.1 of the respective stator pole tooth 2 can have a plurality of depressions 2.2 and, as a result, a plurality of, in particular two, opposing outer edges

2.3, which are each formed in the form of a barb. Also, only one recess 2.2 can be introduced with two outer edges 2.3. In this case, the barbs are mirrored within a pole tooth or rotated by 180 ° relative to one another, so that protection against spinning in both directions of rotation is ensured. In addition, the two outer edges 2.3 can be arranged at a predetermined distance a from one another in order to be able to reduce the surface pressure. That is, only the protruding outer edges 2.3 engage in the housing inner wall 6.1, since the recess 2.2 does not touch the housing inner wall 6.1. The distance a may further correspond to the width of the recess 2.2. Depending on the specification, a further recess 2.4 may additionally be introduced into the depression 2.2, which serves to receive and fix gripping tools for mounting the stator 1 and the stator core 3.

When joining the stator 1 in the housing 6, the stator 1 is first folded and joined to the cylindrical shape. Subsequently, the housing 6, z. B. one or more parts, pressed onto the stator 1 with such a force that the outer edges 2.3 are pressed into the housing inner wall 6.1 and inserted there positive and non-positive. Thus, a stable, in particular positive and non-positive connection is given between the housing 6 and stator 1. An additional Liehe cohesive connection, such. B. gluing or

Plastic syringes, is not required. The shape of the barbs of the outer edges 2.3, which in the housing inner wall

6.1 in the joined state, allows an increase in the stable connection of the housing 6 and stator 1. Alternatively, the stator 1, i. the stator 3, in the

Housing 6 joined, for example, pressed, be.

Alternatively to the sharp-edged design of the recess

2.2 by the outer edges 2.3, the recess 2.2 with a radially outwardly standing, in particular sharp or bent outward elevation 2.5 be provided. Such an embodiment of the respective stator pole tooth 2 is shown in more detail in FIG. The survey 2.5 allows a simple and quick intervention when compressing the housing 6 and stator 1 in the housing inner wall 6.1. In this case, the survey 2.5 preferably also has a hook shape, so that a spin protection is given at least in one or both directions of rotation.

A further alternative embodiment for a one-piece stator 1 is shown in more detail in FIG. The stator 1 in this case comprises a stator packet 3, which is shown in detail in FIG. is conventionally formed of a number of identically stacked and tooth-like structured Einzelblecheή. In the surface 3.1 of the stator core 3, in an analogous manner, as described above under FIG. 1, at least one depression 2.2 is introduced. A resulting 2.3 outer edge engages the housing inner wall 6 when the stator 3 in the housing S actual press-fitted or ^■ vice versa.

FIG. 5 shows a further embodiment for a multi-part stator 1 with a plurality of stator pole teeth 2. In each case, such a depression 2.2 is introduced per stator pole tooth 2 in its surface 2.1 and thus in the upper surface 3.1 of the stator core 3. hende outer edge 2.3 is formed. In detail, the individual Statorpolzahn 2 is shown in Figure 6 in more detail. The. single outer edge 2.3 engages in the housing inner wall 6.1 as described above in the pressed state in the housing 6 of the stator 3. Depending on the specification, the outer edge 2.3 of the respective Statorpolzahns 2 is executed in this embodiment in the form of a barb. The barbs of adjacent Statorpolzahne 2 are mirrored to each other or 180 °. turned introduced. This allows a particularly good protection against rotation. '

Reference sign list

1 stator

2 stator pole tooth

2.1 surface

2.2 deepening

2.3 outer edge

2.4 Survey

4 rotor shaft

6 housing

6.1 Housing inner wall

Claims

claims

1. stator (1) for an electric motor, comprising a stator (3) which is surrounded by a housing (6) and its housing inner wall (6.1) facing surface (2.1, 3: 1) provided with at least one recess (2.2) is, with a resulting outer edge (2.3) engages in the housing inner wall (6.1).

2. Stator according to claim 1, wherein the recess (2.2) at least partially, in particular one or both sides is sharp-edged.

3. Stator according to claim 1 or 2, wherein the outer edge (2.3) positively and non-positively in the housing inner wall (6.1) engages.

4. Stator according to one of the preceding claims, wherein at least the upper edge of the outer edge (2.3) forms the surface (2.1, 3.1) of a Statorpolzahns (2) and / or the stator (3.1).

5. Stator according to claim 4, wherein the outer edge (2.3) is in the form of a barb.

6. Stator according to claim 4 or 5, wherein at least two outer edges (2.3) at a predetermined distance (a) to each other in the surface (2.1, 3.1) of a Statorpolzahns (2) and / or the stator core (3) are introduced.

7. stator (5) according to any one of claims 4 to 6, wherein two opposite radially extending outer edges (2.3) of the recess (2.2) are in the form of a respective barb.

8. Stator according to one of the preceding claims 1 to 7, wherein the recess (2.2) is provided with a radially outward elevation (2.5).

9. Stator according to one of the preceding claims 1 to 8, wherein the housing (6) made of metal or other suitable material is formed.

10. Stator according to one of the preceding claims 1 to 9, wherein the stator core (3) is formed in one or more parts.

11. A stator according to claim 10, wherein a multi-part stator (3) is formed from a predetermined number distributed over the Um'fang individual Statorpolzähne (2), which in turn are formed in the longitudinal axis of the stator core (3) in turn from identical stacked individual sheets ,

12. Stator according to claim 10, wherein a one-piece Statorpa- ket (3) from a predetermined number of identical "stacked one above the other and according to the tooth-like structured individual sheets is formed.

13. Electric motor with a stator (1) according to one of the preceding claims 1 to 12.

14. A method for producing a stator (1) with a stator (2) and a surrounding housing (6) for an electric motor, in particular according to one of claims 1 to 12, wherein in the housing inner wall (6.1) facing 0- surface of the Stator package (3) at least one recess (2.2) is introduced, whose at least one outer edge (2.3) during the joining of the cylindrical stator core (3) with the housing (6) in the housing inner wall (6.1) is pressed.