Stator of an electric machine

Abstract

Stator of an electric machine (2) with a stator lamination stack (3) comprising a stack of laminations (4) and on which at least one positive locking element (5), in particular a positive locking groove and / or positive locking tooth, is formed along its outer circumference, which is provided for fixing the stator to a machine housing (6) and is designed to form a press fit with a counter-positive locking element (15), in particular a housing tooth or a housing groove of the machine housing (6), or with an intermediate element (16), in particular a T-nut, wherein the respective positive locking element (5) has two opposing flanks (5f) for interacting with the respective counter-positive locking element (15) or with the respective intermediate element (16) and extends in particular in an axial direction with respect to a stator axis (1a), characterized by the fact that at least one flank (5f) of the respective positive locking element (5) has a flank ribbing (10) comprising projecting ribs (11) and recessed sections (12) relative to the projecting ribs (11).

Description

State of the art

[0001] The invention relates to a stator of an electrical machine according to the preamble of the main claim.

[0002] A stator of an electric machine is already known from EP3748816 A1, comprising a stator lamination stack with a stack of laminations and several positive locking elements, in particular positive locking teeth, formed along its outer circumference. These positive locking elements are designed for fixing the stator to a machine housing and are each configured to form a contact with a corresponding positive locking element. The positive locking elements, designed as positive locking teeth, each have two opposing flanks for interacting with the corresponding positive locking element and extend, in particular, in the axial direction with respect to a stator axis. The corresponding positive locking elements are grooves in the machine housing.The pressure between the positive locking teeth of the stator lamination stack and the housing grooves of the machine housing can cause mechanical stresses in the stator lamination stack, which negatively affect the magnetic properties of the laminations, thus reducing the power of the electric machine. Advantages of the invention

[0003] In contrast, the stator of an electric machine according to the invention, with the characterizing features of the main claim, has the advantage that it provides a stator fixation that generates fewer mechanical stresses in the stator lamination stack and thus impairs the magnetic properties of the laminations less. This allows the power output of the electric machine to be further increased.

[0004] This is achieved according to the invention by having at least one flank of the respective positive locking element having flank ribbing that includes projecting ribs and sections recessed relative to the projecting ribs.

[0005] Due to the flank ribbing according to the invention, fewer stresses are generated in the stator lamination stack than in the prior art, because only a part of the lamination plates of the stator lamination stack is locally subjected to pressure per positive locking element.

[0006] The stator fixing also has lower tolerance requirements, allowing for increased joining tolerances. This eliminates the need for post-processing of the stator lamination stack to meet joining tolerances. Furthermore, no heating of either component is required to join the stator fixing. Overall, this can reduce manufacturing costs.

[0007] The measures listed in the dependent claims enable advantageous further developments and improvements of the stator of an electrical machine specified in the main claim.

[0008] It is particularly advantageous if both flanks of the respective positive locking element have flank ribbing. In this way, very low joining forces can be achieved for joining the stator fixing.

[0009] It is highly advantageous if the ribs and recessed sections of the respective flank ribbing are formed on different laminations and arranged axially in such a way that at least two separate gaps are formed on each flank, into which an adjacent rib can be bent. This makes the flank ribbing more easily deformable. Part of the bending deformation is elastic. The stator can therefore be joined with lower joining forces than in the prior art, resulting in even less stress being generated locally in the stator lamination stack and further minimizing the degradation of the magnetic properties of the laminations.

[0010] It is further advantageous if the ribs of the respective flank ribs are designed to form a contact with a mating element or intermediate element. It is also advantageous if recessed sections of the respective flank are provided relative to the ribs to form a joint clearance with the mating element or intermediate element. In this way, only a portion of the laminations of the stator core is subjected to local pressure for each mating element, thereby generating fewer stresses in the stator core.

[0011] It is advantageous if several, and in particular all, sheet metal laminations have several contour elements on their outer circumference, especially lamination recesses and / or lamination teeth, to form at least one positive locking element. In this way, the contour elements of the stacked sheet metal laminations can form the at least one positive locking element on the outer circumference of the stator lamination stack.

[0012] It is also advantageous if the respective contour element of the respective sheet metal lamella a. a rib on one flank and a recessed section on the other flank or b. forms a rib or a recessed section on both flanks. According to these advantageous variations, the flank ribbing can be produced very easily.

[0013] Furthermore, it is advantageous if, according to one variant, the contour elements of the respective sheet metal lamella have the same width and are arranged at different angular intervals along the circumference, or, according to another variant, if they have two different widths and are arranged at the same angular intervals along the circumference. According to this further variant, the first width of a contour element is used to create a pressure point, and the second width of a contour element is used to create a joint clearance. In this way, the side ribbing can be produced very easily.

[0014] Furthermore, it is advantageous if the sheet metal lamellae are formed congruently with contour elements and are each rotated by an angle of rotation around the stator axis and / or arranged laterally reversed to form the flank ribbing. In this way, the flank ribbing can be produced with only one type of sheet metal lamella, so that only one stamping tool is required to punch out this type of sheet metal lamella.

[0015] It is advantageous if cooling channels, in particular cooling grooves, are provided between the positive locking elements of the stator, especially if they run in the axial direction. In this way, in addition to stator fixation, stator cooling can be implemented on the outer circumference of the stator lamination stack.

[0016] The invention further relates to a machine arrangement comprising a machine housing and a stator according to the invention arranged in the machine housing. The machine housing has at least one mating positive locking element, in particular a housing groove or a housing tooth, for direct or indirect interaction with a positive locking element of the stator. A press fit is provided between the respective positive locking element of the stator and the associated mating positive locking element of the machine housing. Alternatively, an intermediate element, in particular a T-nut, can be arranged with a press fit in the respective positive locking element and the respective mating positive locking element.

[0017] Several positive locking elements and counter-locking elements can be arranged along the circumference of the machine arrangement, in particular with the same angular spacing. drawing

[0018] Exemplary embodiments of the invention are shown in simplified form in the drawing and explained in more detail in the following description.

[0019] They show: Fig. 1 a stator according to a first embodiment which has three slot-shaped positive locking elements on its outer circumference into which slot blocks for fixing the stator to a machine housing can be pressed, Fig. 2 a partial view of one of the groove-shaped positive locking elements of the stator according to Fig. 1 with flank ribs according to the invention, Fig. 3 a sheet metal lamella of the stator after Fig. 1 with contour elements for forming the form-fitting elements, Fig. 4 a variant of the flank ribbing according to the invention Fig. 2, Fig. 5 a further variant of the flank ribbing according to the invention Fig. 2, Fig. 6 a stator according to a second embodiment, which has three tooth-shaped positive locking elements on its outer circumference that can be pressed into housing grooves of the machine housing and Fig. 7 a partial view of one of the tooth-shaped positive locking elements of the stator according to Fig. 6 with flank ribs according to the invention. Description of the exemplary implementations

[0020] Fig. Figure 1 shows a stator according to a first embodiment, which has three groove-shaped positive locking elements on its outer circumference, into which slot blocks for fixing the stator to a machine housing can be pressed.

[0021] The stator 1 of an electric machine 2 has a stator lamination stack 3, which comprises a stack of laminations 4 and on which at least one positive locking element 5, in particular a positive locking groove and / or a positive locking tooth, is formed along its outer circumference. The respective positive locking element 5 is provided for fixing the stator to a machine housing 7. The respective positive locking element 5 can engage with a counter-positive locking element 15, in particular a housing tooth or a housing groove of the machine housing 7, or as shown in Fig. Figure 1 shows a press fit with an intermediate element 16, in particular a T-nut. The machine housing 7 has at least one counter-positive locking element 15 for direct or indirect interaction with a positive locking element 5 of the stator 1. The machine housing 7 and the stator 1 arranged in the machine housing 7 form a machine assembly 20.

[0022] After Fig. 1 The machine housing 7 has several counter-locking elements 15, in particular housing grooves, along its inner circumference for indirect or direct interaction with the positive locking elements 5 of the stator 1. The several positive locking elements 5 and counter-locking elements 15 are arranged along the circumference of the machine arrangement, in particular with the same angular distance α.

[0023] The intermediate elements 16, in particular T-nuts, are arranged with a press fit in the positive locking elements 5 and the counter-positive locking elements 15.

[0024] The stator fixing can serve to support the torque of the stator 1 on the machine housing 7 or to align the stator 1 in the machine housing 7.

[0025] The stator lamination stack 3 has, for example, several positive locking elements 5 along its outer circumference, according to Fig. 1 for example three positive locking elements 5. The positive locking elements 5 are according to Fig. 1 for example, designed in a groove shape. The respective positive locking element 5 has two opposing flanks 5f for interaction with the respective counter-positive locking element 15 or with the respective intermediate element 16 and extends in particular in the axial direction with respect to a stator axis 1a. A perpendicular line on the respective flank 5f points in the circumferential direction. Cooling channels 8, in particular cooling grooves, can be provided in the circumferential direction between the positive locking elements 5 of the stator 1, extending particularly in the axial direction. However, the cooling channels 8 can also be omitted.

[0026] The laminations 4 of the stator lamination stack 3 are firmly connected to each other, for example by gluing or interlocks.

[0027] Fig. Figure 2 shows a partial view of one of the groove-shaped positive locking elements of the stator. Fig. 1 with flank ribbing according to the invention.

[0028] According to the invention, at least one flank 5f of the respective positive locking element 5 has a flank ribbing 10 comprising projecting ribs 11 and recessed sections 12 relative to the projecting ribs 11.

[0029] According to the first embodiment in Fig. 2 Both flanks 5f of the respective positive locking element 5 have a flank ribbing 10.

[0030] The projecting ribs 11 of the respective flank ribbing 10 are designed to form a press fit with a counter-form-locking element 15 or an intermediate element 16. The recessed sections 12 of the respective flank 5f, relative to the ribs 11, are designed to form a joint clearance with the counter-form-locking element 15 or intermediate element 16.

[0031] The ribs 11 and recessed sections 12 of the respective flank ribbing 10 are according to Fig. 2, Fig. 4 and Fig. 5 each formed on different sheet metal lamellae 4 and arranged in the axial direction with respect to the stator axis 1a in such a way that at least two separate gap spaces 13 are formed on the respective flank 5f, into which an adjacent rib 11 can be bent.

[0032] The stator 1 has stator teeth 14 on its inner circumference, the tooth flanks 14f of which are unribbed. The flank ribbing 10 is thus formed without creating a ribbing of the tooth flanks 14f of the stator teeth 14.

[0033] The transition 17 from the respective flank 5f of the respective groove-shaped form-locking element 5 to a groove base 5g is, for example, designed in the form of an undercut.

[0034] Fig. Figure 3 shows a sheet metal lamella of the stator. Fig. 1 with contour elements for forming the form-fitting elements.

[0035] Several, in particular all, laminations 4 of the stator lamination stack 3 have several contour elements 6 on their outer circumference according to the Fig. 3, in particular lamellar recesses and / or lamellar teeth, to form a positive locking element 5 in the stator lamination stack 3. In the circumferential direction between the contour elements 6 of the respective sheet metal lamella 4, cooling elements 9, in particular lamella recesses, can be provided to form the cooling channels 8 in the stator lamination stack 3.

[0036] Fig. Figure 4 shows a variant of the flank ribbing according to the invention. Fig. 2.

[0037] Fig. Figure 4 shows sheet metal lamellae 4.1, in which the respective contour element 6 of the respective sheet metal lamella 4.1 forms a rib 11 on both sides 6f. Furthermore, it shows Fig. 4 sheet metal lamellae 4.2, in which the respective contour element 6 of the respective sheet metal lamella 4.2 forms a recessed section 12 on both flanks 6f.

[0038] The sheet metal lamellae 4 with contour elements 6 according to Fig. The four laminations are identical, meaning they are of the same type. To form the flank ribbing 10, the laminations 4 are each rotated by an angle around the stator axis 1a and / or arranged in reverse.

[0039] The several contour elements 6 of the respective sheet metal lamella 4 have according to Fig. 4 two different widths b and are arranged with equal angular spacing β along the circumference, wherein a first width b1 is provided to form a pressure and a second width b2 is provided to form a joint clearance.

[0040] Fig. Figure 5 shows another variant of the flank ribbing according to the invention. Fig. 2.

[0041] Fig. Figure 5 shows sheet metal lamellae 4.3, in which the respective contour element 6 of the respective sheet metal lamella 4.3 forms a rib 11 on one flank 6f and a recessed section 12 on the other flank 6f. Furthermore, Figure 5 shows... Fig. 5 sheet metal lamellae 4.4, in which the respective contour element 6 of the respective sheet metal lamella 4.4 forms a recessed section 12 on both flanks 6f.

[0042] The sheet metal lamellae 4 with contour elements 6 according to Fig. The 5 are also identical in design, i.e., of the same sheet metal lamella type. To form the flank ribbing 10, the sheet metal lamellae 4 are each rotated by an angle of rotation around the stator axis 1a and / or arranged laterally reversed.

[0043] The several contour elements 6 of the respective sheet metal lamella 4 have according to Fig. 5 have the same width b and are arranged with different angular distances β along the circumference.

[0044] Fig. Figure 6 shows a stator according to a second embodiment, which has three tooth-shaped positive locking elements on its outer circumference that can be pressed into housing grooves of the machine housing.

[0045] According to the second embodiment, the positive locking elements 5 are tooth-shaped.

[0046] The respective positive locking element 5 is according to Fig. 6 for forming a press fit with a counter-form-locking element 15, in particular a housing groove of the machine housing 7. The intermediate elements 16 from the first embodiment are omitted in the second embodiment.

[0047] Fig. Figure 7 shows a partial view of one of the tooth-shaped positive locking elements of the stator. Fig. 6 with flank ribs according to the invention.

[0048] According to the second embodiment, several, in particular all, sheet metal laminations 4 of the stator lamination stack 3 have tooth-shaped contour elements 6 on their outer circumference to form a positive locking element 5 in the stator lamination stack 3. The contour elements 6 are therefore laminar teeth.

[0049] Even in the second embodiment, at least one flank 5f of the respective positive locking element 5 has a flank ribbing 10 according to the invention. Fig. 7 have flank ribbing on both sides 5f 10.

[0050] The flank ribbing 10 is produced in the same way as in the first embodiment. QUOTES INCLUDED IN THE DESCRIPTION

[0000] This list of documents cited by the applicant was automatically generated and is included solely for the reader's convenience. The list is not part of the German patent or utility model application. The DPMA accepts no liability for any errors or omissions. Cited patent literature

[0000] EP 3748816 A1

[0002]

Claims

[1] Stator of an electric machine (2) with a stator lamination stack (3) comprising a stack of laminations (4) and on which at least one positive locking element (5), in particular a positive locking groove and / or positive locking tooth, is formed along its outer circumference, which is provided for fixing the stator to a machine housing (7) and is designed to form a press fit with a counter-positive locking element (15), in particular a housing tooth or a housing groove of the machine housing (7), or with an intermediate element (16), in particular a T-nut, wherein the respective positive locking element (5) has two opposing flanks (5f) for interacting with the respective counter-positive locking element (15) or with the respective intermediate element (16) and extends in particular in an axial direction with respect to a stator axis (1a), characterized by, that at least one flank (5f) of the respective positive locking element (5) has a flank ribbing (10) comprising projecting ribs (11) and recessed sections (12) relative to the projecting ribs (11). [2] Stator according to claim 1, characterized by , that both flanks (5f) of the respective positive locking element (5) have flank ribbing (10). [3] Stator according to any one of the preceding claims, characterized by , that the ribs (11) and recessed sections (12) of the respective flank ribbing (10) are each formed on different sheet metal lamellae (4) and are arranged in an axial direction in such a way that at least two separate gap spaces are formed on the respective flank (5f), into which an adjacent rib (11) can be bent. [4] Stator according to any one of the preceding claims, characterized by, that the protruding ribs (11) of the respective flank ribbing (10) are provided to form a press fit with a counter-form locking element (15) or intermediate element (16) and that the recessed sections (12) of the respective flank (5f) are provided to form a joining clearance to the counter-form locking element (15) or intermediate element (16). [5] Stator according to any one of the preceding claims, characterized by , that several, in particular all, sheet metal lamellae (4) have several contour elements (6) on their outer circumference, in particular lamella recesses and / or lamella teeth, to form the at least one positive locking element (5). [6] Stator according to claim 5, characterized by , that the respective contour element (6) of the respective sheet metal lamella (4) a. on one flank (6f) a rib (11) and on the other flank (6f) a recessed section (12) or b. forms a rib (11) or a recessed section (12) on both flanks (6f). [7] Stator according to one of claims 5 or 6, characterized by , that the contour elements (6) of the respective sheet metal lamella (4) a. have the same width (b) and are arranged at different angular intervals (β) along the circumference b. have two different widths and are arranged with equal angular spacing (β) along the circumference, wherein a first width (b1) is provided to form a pressure and a second width (b2) is provided to form a joint clearance. [8] Stator according to any one of claims 5 to 7, characterized by , that the sheet metal lamellae (4) are formed congruently with contour elements (6) and are each rotated by an angle of rotation around the stator axis (1a) and / or arranged in reverse to form the flank ribbing (10). [9] Stator according to any one of the preceding claims, characterized by, that cooling channels (8), in particular cooling grooves, are provided between the positive locking elements (5) of the stator (1), which extend in particular in the axial direction. [10] Machine arrangement comprising a machine housing (7) and a stator (1) arranged in the machine housing (7) according to one of the preceding claims, wherein the machine housing (7) has at least one counter-form-locking element (15), in particular a housing groove or a housing tooth, for indirect or direct interaction with a form-locking element (5) of the stator (1), wherein a press fit is provided between the respective form-locking element (5) of the stator (1) and the associated counter-form-locking element (15) of the machine housing (7), or wherein an intermediate element (16), in particular a T-nut, is arranged with a press fit in the respective form-locking element (5) and the respective counter-form-locking element (15). [11] Machine arrangement according to claim 10, characterized by , that several positive locking elements (5) and counter-locking elements (15) are arranged along the circumference of the machine arrangement, in particular with the same angular distance (α).

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