STATOR FOR AN ELECTRIC MOTOR

Abstract

A stator for an electric motor, wherein the stator has a laminated stator core which is formed from a multitude of individual teeth that can be arranged in a ring around an axis of rotation of the electric motor and interconnected in the circumferential direction, wherein each individual tooth of the plurality of individual teeth is flanked on both sides along the circumferential direction by a further individual tooth from among the plurality of individual teeth and has a connection portion for mechanically fixing the individual tooth to the individual teeth by which it is flanked, and wherein at least some of the individual teeth each have a pressing portion for elastic and/or plastic deformation and establishment of a press-fit connection between the laminated stator core and a radially inner axle, so that, upon joining of the stator to the axle, the stator can be fixed to the axle through the deformation of the pressing portions and a force acting on the axle as a result of the deformation between laminated stator core and axle.

Claims

1. A stator for an electric motor having an axle (20), the stator comprising: a laminated stator core (10) which is formed from a plurality of individual teeth (11) arranged in a ring around an axis of rotation (R) of the electric motor and interconnected in the circumferential direction (U), wherein each individual tooth (11) of the plurality of individual teeth is flanked on both sides along the circumferential direction (U) by a further individual tooth (11) from among the plurality of individual teeth (11) and has a connection portion (12) for mechanically fixing the individual tooth (11) to the individual teeth (11) by which it is flanked, and wherein at least some of the plurality of individual teeth (11) each have a radially inner pressing portion (13) for elastic and/or plastic deformation and establishment of a press-fit connection between the laminated stator core (10) and an axle (20) of the electric motor configured so as to extend through the laminated stator core (10) along the axis of rotation (R) and coaxially with the axis of rotation (R), so that, upon joining of the stator to the axle (20), the stator can be fixed to the axle (20) through the deformation of the pressing portions (13) and a force acting on the axle (20) as a result of the deformation between laminated stator core (10) and axle (20).

2. The stator as set forth in claim 1, wherein the pressing portions (13) each have a web (14) extending in the radial direction (X) and at least one lever arm (15) that is connected to the web (14) and protrudes in the circumferential direction (U) relative to the web (14) with a contact surface (16) that points inward in the radial direction (X) for contact with the axle (20), and wherein the at least one lever arm (15) can be deflected and deformed in the radial direction (X) during joining, so that a pressing force can be exerted on the axle (20) as a result of the deflection and deformation.

3. The stator as set forth in claim 2, wherein the lever arms (15) together define a sleeve-shaped pressing contour with their contact surfaces (16) that is coaxial with the axis of rotation (R) and oversized compared to an outer contour (21) of the axle (20), so that the lever arms (15) are pressed radially outward when joined to the axle (20).

4. The stator as set forth in claim 2, wherein the contact surfaces (16) of the lever arms (15) are concave.

5. The stator as set forth in claim 2, wherein the pressing portions (13) each have two lever arms (15) which protrude in the circumferential direction relative to the web (14), which lever arms (15) are situated opposite one another and protrude in opposite directions relative to the web (14).

6. The stator as set forth in claim 5, wherein at least one groove (17) is respectively formed on the pressing portions (13) between the two lever arms (15), which decouples the lever arms (15) from one another and separates the lever arms (15) from one another so that they can be deflected and deformed independently of one another.

7. The stator as set forth in claim 2, wherein the lever arms (15) are each connected to the web (14) via a connection portion (18) that is instantiated particularly as a taper by means of which a force acting during joining can be predetermined.

8. The stator as set forth in claim 1, wherein the pressing portions (13) are embodied such that, due to the deformation of the pressing portions (13), a force acting on the connection portions (12) and separating the individual teeth (11) from one another is smaller during joining than a maximum permissible force, so that the individual teeth (11) do not separate during joining.

9. An electric motor with a stator as set forth in claim 1.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

[0024] Other advantageous refinements of the disclosure are characterized in the subclaims and/or depicted in greater detail below together with the description of the preferred embodiment of the disclosure with reference to the figures. In the drawings:

[0025] FIG. 1 shows a perspective representation of a laminated stator core joined to an axle;

[0026] FIG. 2 shows detail from a plan view of a laminated stator core joined to an axle; and

[0027] FIG. 3 shows a pressing portion of a single tooth of a laminated stator core joined to an axle.

DETAILED DESCRIPTION

[0028] The figures are schematic examples. Same reference symbols in the figures indicate same functional and/or structural features.

[0029] FIG. 1 shows a perspective view of a laminated stator core 10 joined to an axle 20. If, as is the case here, a laminated stator core 10 is formed from a multitude of individual teeth 11 that are interconnected in the circumferential direction U, it is possible during joining of the laminated stator core 10 to the axle 20 for impermissibly high forces to occur in the region of the connection portions 12 by which the Individual teeth 11 are mechanically interconnected or fixed to one another in the circumferential direction U, resulting in the release of the mechanical connection and separation of the individual teeth 11 from one another and thereby dismantling or even damaging the laminated stator core.

[0030] In order to prevent such dismantling or damage to the laminated stator core 10, at least some of the individual teeth 11 and — especially preferably, as shown in FIGS. 1 to 3 — all of the individual teeth 11 have a pressing portion 13 that is designed to join the laminated stator core 10 to the axle 20.

[0031] The pressing portion 13 is located radially to the axis of rotation R about which a rotor of the electric motor can rotate around the stator, on the inside, and closes off the individual teeth 11 in the radial direction X inward or toward the axle 20.

[0032] FIG. 2 corresponds to detail of a plan view of the laminated stator core 10 with the axle 20 joined thereto, as illustrated by FIG. 1. This makes it particularly clear that the laminated stator core 10 is in contact with the axle 20 exclusively through the pressing portions 13 of the individual teeth 11 of the laminated stator core 10, and that the pressing portions 13 of the individual teeth 11 together define a sleeve-shaped pressing contour that corresponds to the outer contour of the axle 20 but is oversized relative thereto. Due to the oversize, the axle 20 can be arranged in and pressed into the pressing contour formed by the pressing portions 13, so that a deformation of the pressing portions 13 or a deformation of the lever arms 15 of the pressing portions 13 shown in FIG. 3 occurs during the pressing-in, whereby the lever arms 15 are pressed radially outward and exert a pressing force on the axle 20.

[0033] FIG. 3 shows an enlarged view of a single pressing portion 13, making it clear that the pressing portion 13 is terminated radially inward by two lever arms 15 which are separated from one another by a weakening or a groove 17, but each of which is connected to the web 14 by means of a taper or a connection portion 18.

[0034] The connection portions 18 and the groove 17 enable the lever arms 15 to be deflected independently of one another, with these each having a free end opposite their end that merges into the connection portion 18, so that when they are joined to the axle 20, they initially yield elastically and can be plastically deformed preferably at the end of the elastic deformation.

[0035] The lever arms 15 each have a contact surface 16 for contact with the axle 20, with each of the contact surfaces 16 or the two contact surfaces 16 of the pressing portion 13 together describing a concave shape or possibly being concave. The two contact surfaces 16 provide two contact regions or contact points for each pressing portion via which the respective individual tooth 11 rests against the axle 20.

[0036] In order to prevent the individual teeth 11 that are interconnected at the connection portions 12 from being separated from one another when the axle 20 is joined, i.e., pressed into the stator or into the pressing contour formed by the pressing portions 13, the connection portions 18 are embodied such that, during joining and an associated deflection of the lever arms 15 at the connection portions 12, a force acts which is smaller than a maximum permissible force by which the individual teeth 11 at the connection portions 12 would be separated from one another.

[0037] The disclosure is not limited in its execution to the abovementioned preferred exemplary embodiments. Rather, a number of variants are conceivable that make use of the illustrated solution even in the form of fundamentally different embodiments.