Stator of an electrical machine

Abstract

The invention relates to a stator (1) of an electrical machine with a stator laminated core (2) and with a housing (3), wherein the stator laminated core (2) is formed with a plurality of stator laminates (4) which are arranged to form a laminated core by an adjacent arrangement of the stator laminates (4) and are arranged in the housing (3), wherein the stator laminates (4) have screw eyes (5) with through holes (6) for the passage of axial screws (7) for the axial screwing and clamping of the stator laminated core (2), wherein the screw eyes (5) are arranged distributed over the circumference of the stator laminated core (2) and elastic contact areas (13) are provided between each adjacently arranged screw eyes (5), which contact areas lie radially on the outside of the housing (3) under radial prestress.

Description

[0001] The invention relates to a stator of an electrical machine, in particular of a motor vehicle. The invention also relates to an electrical machine with a stator.

[0002] Electrical machines consist of a stator and a rotor. The rotor rotates, and the torque delivered by the rotor is supported by the stator. The stator typically consists of a laminated core arranged and secured in a housing. The laminated core, with its many stacked laminations, is usually secured using an interference fit, in which the laminations of the laminated core are inserted into the housing with interference. The laminations and the housing are thermally treated so that the laminations can be inserted into the housing without axial force and are held securely in the housing even after cooling and under operating conditions.

[0003] However, this transverse interference fit creates stresses in the stator laminations and in the housing, with the stresses in the stator laminations having a negative impact on the consumption of the electrical machine.

[0004] For small electric motors with a few stator laminations in the stator core, a known solution is to clamp the stator laminations axially using screws. This has the disadvantage of a temperature-dependent expansion behavior of the self-bonding varnish on the stator laminations. Over a temperature cycle, this can lead to plastic elongation of the screws and thus to a loss of preload.

[0005] Electrical machines with axial screw connection of the laminated cores are known, for example, from DE 37 04 157 C2 or from DE 10 2021 212 359 A1.

[0006] US 10 336 299 B2 discloses a stator according to the preamble of claim 1.

[0007] DE 10 2020 204 725 A1 discloses an electric machine with a stator, wherein the stator is arranged in a housing in a rotationally fixed manner and is connected to the housing by means of connecting elements, wherein the connecting elements connect the stator rigidly in the circumferential direction and flexibly in the radial direction.

[0008] US 2020 / 0 186 001 A1 discloses a stator of an electric machine with an outwardly arranged circular edge and radially inwardly formed teeth, wherein openings are arranged distributed over the circumference adjacent to the outwardly arranged edge.

[0009] DE 10 2021 212 362 A1 discloses a stator of an electric machine with an externally arranged circular edge with screw-on eyes and radially inwardly formed teeth, wherein openings are arranged distributed over the circumference adjacent to the externally arranged edge.

[0010] The task is to create an improved stator of an electrical machine which reduces or eliminates the disadvantages described above and yet allows the production of an electrical machine with low consumption.

[0011] The problem of the stator is solved with the features of claim 1.

[0012] One embodiment of the invention relates to a stator of an electrical machine with a stator laminated core and with a housing, wherein the stator laminated core is formed with a plurality of stator laminates which are arranged to form a laminated core by an adjacent arrangement of the stator laminates and are arranged in the housing, wherein the stator laminates have screw eyes with through holes for the passage of axial screws for axially screwing and clamping the stator laminated core, wherein the screw eyes are arranged distributed over the circumference of the stator laminated core and elastic contact areas are provided between each adjacently arranged screw eyes, which contact areas bear radially on the outside of the housing under radial prestress. This ensures that the stator laminated core is securely arranged and clamped in the housing and that the stator laminates are centered.

[0013] According to the invention, the stator laminations are essentially formed with a circular ring-shaped region, and the screw bosses and / or the contact areas protrude radially outward from the ring area. The contact areas are preferably located radially further outward than the screw bosses. This enables a flexible connection to the outer housing because the ring area itself does not rest against the housing. This enables the centering of the stator laminations.

[0014] It is also advantageous if the screw bosses and the contact areas are spaced apart from each other in the circumferential direction. This allows for a distribution of the contact areas, with the screw bosses not in contact with the housing positioned between them and set back radially.

[0015] According to the invention, the contact area is formed by webs extending in the circumferential direction and by webs extending in the radial direction. This allows a radially softer area to be formed, which allows the stator lamination to be centered in the housing.

[0016] It is also preferred if the webs form an elastic supporting structure. This achieves a defined elasticity, which allows for the centering of the stator laminations.

[0017] According to the invention, first webs extending radially outward from the annular region are provided, which support a second web extending in the circumferential direction. Starting from the second web extending in the circumferential direction, third webs extending radially outward are provided, which support a further fourth web extending in the circumferential direction. This creates elastic regions and stable regions that allow secure support while still providing a defined degree of elasticity for centering.

[0018] It is also advantageous if the fourth web forms a contact surface for the housing. This creates a defined, flat contact area to achieve compression and transmit force for centering.

[0019] It is also advantageous if the radially extending first and third webs are offset from each other in the circumferential direction. This provides a defined, stable support for achieving compression and transmitting force for centering.

[0020] In one embodiment, it is expedient for the stator laminations to be coated, in particular with a bonding varnish. This provides electrical insulation between the stator laminations and, if necessary, adhesive bonding of the stator laminations.

[0021] The object of the electrical machine is achieved with the features of claim 7.

[0022] An embodiment of the invention relates to an electrical machine with a rotor and with a stator, wherein the stator is designed according to a configuration according to the invention.

[0023] The invention will be explained in detail below using an exemplary embodiment with reference to the drawings. In the drawings: Fig. 1 a schematic sectional view of an embodiment of a stator of an electrical machine, and Fig. 2 a view of an enlarged section of the stator laminated core.

[0024] The Fig. 1 shows a sectional view of a stator 1 of an electrical machine with a stator core 2 and with a housing 3. The Fig. 2 shows an enlarged section of the stator core 2. The electric machine typically has a rotor and a stator 1.

[0025] The stator lamination stack 2 consists of a plurality of stator laminations 4 that are stacked to form the stator lamination stack 2, which is also referred to as packaging. Typically, the stator lamination stack 2 consists of approximately 500 to 1000 or more stator laminations 4, each of which is arranged adjacent to one another.

[0026] The stator laminated core 2 is arranged in the housing 3 under a compression at the edge of the housing 3.

[0027] Furthermore, the stator laminations 4 have screw eyes 5 with through holes 6 for the passage of axial screws 7 for the axial screwing and clamping of the stator lamination package 2.

[0028] As from the Fig. 1, the screw eyes 5 are arranged distributed over the circumference of the stator laminated core 2.

[0029] Between each two adjacently arranged screw eyes 5, elastic contact areas 13 are provided, which are placed radially outside on the housing 3 under radial preload, as shown in Fig. 1 is shown.

[0030] In the embodiment shown, the stator laminations 4 are essentially formed with a circular ring-shaped annular region 8, wherein the screw eyes 5 and / or the contact regions 13 protrude radially outwards from the annular region 8.

[0031] As can also be seen, the screw bosses 5 and the contact areas 13 are arranged at a distance from one another in the circumferential direction. This provides a defined spatial separation, so that the contact areas 13 can elastically deform to a defined extent in the radial direction without the influence of the screw bosses 5, in order to allow centering of the stator laminations 4.

[0032] According to the embodiment shown, the contact area 13 is formed by webs 9, 10 extending in the circumferential direction and by webs 11, 12 extending in the radial direction.

[0033] The webs 9, 10, 11, 12 form an elastic supporting structure, which allows a defined radial elastic design.

[0034] The supporting structure is formed in such a way that, starting from the annular region 8, radially outwardly extending first webs 11 are provided, which carry a second web 9 extending in the circumferential direction, and, starting from the second web 9 extending in the circumferential direction, radially outwardly extending third webs 12 are provided, which carry a further fourth web 10 extending in the circumferential direction.

[0035] The fourth web 10 forms a contact surface 14 for the housing 3, against which the inner wall of the housing 3 rests.

[0036] According to the illustrated embodiment, the first webs 11, which extend in the radial direction, and the third webs 12 are arranged offset from one another in the circumferential direction. This allows for an elastic configuration between the webs 9 and 10, which serves as a centering element.

[0037] Furthermore, it is expedient for the stator laminations 4 to be coated, in particular with a bonding varnish. This serves to electrically insulate the stator laminations 4 and, if necessary, to bond them together. List of reference symbols 1 stator 2 stator laminations 3 housings 4 Stator sheet 5 screw eyes 6 through holes 7 Axial screw 8 ring area 9 second bridge 10 fourth bridge 11 first bridge 12 third bridge 13 Investment area 14 contact surface

Claims

[1] Stator (1) of an electrical machine with a stator laminated core (2) and with a housing (3), wherein the stator laminated core (2) is formed with a plurality of stator laminates (4) which are arranged to form a laminated core by an adjacent arrangement of the stator laminates (4) and are arranged in the housing (3), wherein the stator laminates (4) have screw eyes (5) with through holes (6) for the passage of axial screws (7) for the axial screwing and clamping of the stator laminated core (2), wherein the screw eyes (5) are arranged distributed over the circumference of the stator laminated core (2) and elastic contact areas (13) are provided between each adjacently arranged screw eyes (5), which contact areas lie radially outside on the housing (3) under radial prestress, characterized byin that the stator laminations (4) are essentially formed with a circular ring-shaped annular region (8) and the screw eyes (5) and / or the contact regions (13) protrude radially outwards from the annular region (8), and wherein the contact region (13) is formed by webs (9, 10) extending in the circumferential direction and by webs (11, 12) extending in the radial direction, wherein, starting from the annular region (8), radially outwardly extending first webs (11) are provided, which carry a second web (9) extending in the circumferential direction, and, starting from the second web (9) extending in the circumferential direction, radially outwardly extending third webs (12) are provided, which carry a further fourth web (10) extending in the circumferential direction. [2] Stator (1) according to claim 1, characterized by that the screw eyes (5) and the contact areas (13) are arranged at a distance from one another in the circumferential direction. [3] Stator (1) according to claim 1 or 2, characterized by that the webs (9, 10, 11, 12) form an elastic supporting structure. [4] Stator (1) according to claim 1, 2 or 3, characterized by that the fourth web (10) forms a contact surface (14) for the housing (3). [5] Stator (1) according to one of the preceding claims 1 to 4, characterized by that the first webs (11) and third webs (12) extending in the radial direction are arranged offset from one another in the circumferential direction. [6] Stator (1) according to one of the preceding claims, characterized by that the stator laminations (4) are painted or have a baked enamel coating. [7] Electrical machine with a rotor and with a stator (1), wherein the stator (1) is designed according to one of the preceding claims.

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