Stator of an electrical machine

Abstract

A stator of an electromachine (2) comprising a stator laminate (3) containing sheet metal (8) and extending around a stator shaft (7), having stator teeth (4) and stator slots (5) between the stator teeth (4), wherein within the stator laminate (3) there is provided at least one set (13) of three first stator sub-laminateds (3.1) twisted in opposite directions to clamp the stator coil (6) at clamping points (10) of the stator slots (5), with two of the first stator sub-laminateds (3.1) of each set (13) in one circumferential direction about the stator shaft (7), and the remaining first stator of the set (13) A stator characterized in that a sub-laminated stack (3.1) is twisted in opposite directions, and within the stator slot (5) of the stator stack (3), a protective cylinder (11) is provided in the region of the twisted first stator sub-laminated stack (3.1), and this protective cylinder (11) protects the stator coil (6) from damage caused by the twisted first stator sub-laminated stack (3.1), and is particularly electrically insulating, wherein at least one of the protective cylinders (11) has at least one flange (12), and this flange (12) is bent with respect to the slot section (11.1) of the protective cylinder (11) and is provided so as to be supported by axial bracing against one of the stator teeth (4) of one of the first stator sub-laminated stacks (3.1).

Description

Technical Field

[0001] The present invention starts from the stator of an electric machine based on the generic concept of an independent claim.

Background Art

[0002] Already from DE102021204202A1, there is a stator tooth and a stator slot between the stator teeth, which extends around the stator axis and includes a stator laminate made of thin sheet metal, and a stator coil running in the stator slot. For an electric machine stator, in this stator laminate, at least one set of three first stator partial laminates twisted in opposite directions is provided to clamp the stator coil at the clamping location of the stator slot. Two of the first stator partial laminates of each set are twisted in one circumferential direction around the stator axis, and the remaining first stator partial laminates of the set are twisted in the opposite direction. In the stator slot of this stator laminate, a protective cylinder is provided in the region of the twisted first stator partial laminate, and this protective cylinder protects the stator coil from damage by the twisted first stator partial laminate. Such a stator is known.

Summary of the Invention

[0005] The measures described in the dependent claims enable the advantageous modification and improvement of the stator of the electromachine presented in the independent claim. In one advantageous embodiment, the flange of each protective cylinder is formed on at least one side facing the tooth surface of each stator slot and / or on a narrow surface connecting the sides. The flange of each protective cylinder may be a ring-shaped flange that encircles the cylinder.

[0006] Particularly advantageous is the case where each first stator sub-laminated laminate includes at least one end plate on at least one of both end faces, and the slot contour of this end plate is offset backward from the remaining plates to form a structural space for accommodating the flange of each protective casing. Alternatively, or in addition to this, the flange of each protective casing may be sandwiched between the plates of the stator laminate. In this way, the protective casing is securely fixed in the stator laminate via the flange.

[0007] A further advantage is when multiple, and especially all, protective cylinder flanges of one or one set of the first stator sub-laminated stacks are integrally connected to form a protective cylinder unit, which has a plate section for connecting the protective cylinders, and the plate section of the protective cylinder unit is formed in the plane between two plates of the stator stack. This simplifies the attachment of the protective cylinders, as fewer parts need to be attached to the stator stack.

[0008] A significant advantage is when each protective cylinder extends axially into only one of the first stator sub-laminated stacks in each set, according to the first embodiment, or into all of the first stator sub-laminated stacks in the set, according to the second embodiment. The protective cylinder according to the first embodiment does not need to deform when the first stator sub-laminated stack is twisted. The protective cylinder according to the second embodiment must be able to absorb deformation when the first stator sub-laminated stack is twisted, but has the advantage of requiring fewer parts to be attached to the stator stack. Furthermore, in the embodiment with a rearward-shifted slot contour in the end laminated stack, less iron needs to be removed from the end laminated stack of the first stator sub-laminated stack.

[0009] A further advantage is when the protective cylinder is formed either closed or interrupted by slits in the circumferential direction, with these slits located particularly at the axial corners of the protective cylinder. A closed protective cylinder has the advantage of being highly dimensionally stable and easy to install. A slitted protective cylinder has the advantage that the conductor bundle of the stator coil can be inserted and passed through the protective cylinder more easily, particularly when the protective cylinder is manufactured with a draft angle.

[0010] According to one advantageous embodiment, the slot section of the protective cylinder may be formed in a manner corresponding to the shape of the stator slot, in particular, having a trapezoidal, rectangular, sleeve-shaped, partially trapezoidal, partially rectangular, or U-shaped cross-section.

[0011] Furthermore, it is advantageous if the material of each protective cylinder is plastic, particularly elastomer or thermoplastic elastomer, or ceramic. This ensures that the tooth surfaces of the twisted first stator sub-laminated are covered with an electrically insulating material. A clamping force is applied to the stator coil through the protective cylinder. In the case of elastic plastic for the protective cylinder, the clamping force due to the twisting of the first stator sub-laminated prevents damage to the conductors of the stator coil at the clamping point.

[0012] Furthermore, since each stator slot is permeable to a coolant, particularly oil, along the cooling path, it is advantageous in the protective cylinder if a bypass is provided for the flow to bypass the clamping points, particularly on one of the narrow inner surfaces of the protective cylinder, especially on the narrow inner surface facing or not facing the stator yoke. This allows the coolant to be guided to pass by the clamping points with minimal pressure loss.

[0013] An advantage is when the stator teeth are interconnected via a ring-shaped stator yoke, each having a tooth end formed as a tooth tip, particularly one not facing the stator yoke, the stator slots have slot slits formed between the tooth ends, and radially projecting sections are formed on the narrow faces of each protective cylinder not facing the stator yoke, these projections extending into the respective slot slits and extending axially. This allows for control of meandering flow within the slot gaps of the stator slots. The projections provide local sealing of the slot slits in the clamping area, forcing the flow to pass alongside each clamping area via a bypass in the bottom of the slot. This results in better and / or more uniform cooling of the stator coil conductors.

[0014] A further advantage is provided in the stator stack where at least one second stator sub-stack is located within the stator stack, the second stator sub-stack is positioned between one set of first stator sub-stacks and / or between two sets of first stator sub-stacks, and circumferentially, the conductors of the stator coils in each stator slot of the second stator sub-stack are aligned to run along the stator slot with spacing relative to both tooth surfaces of the stator slot, thereby forming slot gaps within the stator slot. This allows the refrigerant to be guided through the stator slot with less pressure loss.

[0015] To seal the slot slits, a stator sleeve may be provided in the inner diameter of the stator stack. The present invention further relates to an electromachine equipped with a stator according to the present invention.

[0016] Exemplary embodiments of the present invention are shown in the drawings and will be described in detail below. [Brief explanation of the drawing]

[0017] [Figure 1] This is a cross-sectional view of an electromachine equipped with a stator and a rotor. [Figure 2] This is a partial view of a stator according to Figure 1, comprising a plurality of twisted first stator partial stacks, each having a protective cylinder according to the present invention based on a first exemplary embodiment, provided within the stator slot. [Figure 3] This figure shows a first stator sub-laminated assembly according to Figure 2, which includes a protective cylinder according to the present invention based on a first exemplary embodiment. [Figure 4] This is a partial view of a stator according to Figure 1, comprising a plurality of untwisted first stator partial stacks, each having a protective cylinder according to the present invention based on a second exemplary embodiment, located within the stator slot. [Figure 5] Figures 2 to 4 show a first embodiment of the protective cylinder according to the present invention. [Figure 6] This figure shows a second embodiment of the protective cylinder according to the present invention, based on Figures 2 to 4. [Figure 7] This is a further diagram of the protective cylinder based on Figure 5. [Modes for carrying out the invention]

[0018] Figure 1 shows a cross-sectional view of an electromachine equipped with a stator and rotor. The stator 1 according to the present invention of the electric machine 2 includes a stator laminate 3, in which stator teeth 4 and stator slots 5 between the stator teeth 4 are formed, and the stator laminate 3 extends around a stator axis 7. The stator 1 further includes a stator coil 6 running in the stator slots 5. The stator laminate 3 is formed from a stack of thin plates 8, especially sheet metal.

[0019] The stator teeth 4 are interconnected via a ring-shaped stator yoke 9. Each stator slot 5 has a slot bottom 5g facing the stator yoke 9 and a slot slit 5s formed between tooth ends 4e on the side opposite to the slot bottom 5g.

[0020] In each stator slot 5, there is provided only one conductor 15 or a conductor bundle 29 including a plurality of conductors 15, especially a stack of flat conductors, in order to form the electrical stator coil 6.

[0021] In addition to this, the electric machine 2 has a rotor 26 rotatable about the stator axis 7 and a housing 27. An air gap 28 is formed between the stator 1 and the rotor 26. For example, at least one supply path 30 may be formed in the stator laminate 3. This supply path 30 is provided for supplying a refrigerant to the cooling path 17 and leads to the stator slots 5 through slot inlets 5i respectively. In each stator slot 5, from each slot inlet 5i, for example, two cooling paths 17 running in opposite directions and especially in a meandering shape are defined. These cooling paths 17 exit as free jets through slot outlets 5a at the ends of each stator slot 5.

[0022] Alternatively, both coil ends of the stator coil 6 can be arranged in coil end cooling spaces 31 that terminate along the dashed line in the housing 27 respectively. These two coil end cooling spaces 31 are in fluid communication with each other through a cooling path 15, especially in a meandering shape, passing through the stator slot 6.

[0023] Figure 2 shows a partial view of the stator based on FIG. 1, which includes a plurality of twisted first stator partial laminations according to the invention based on the first exemplary embodiment, with a protective cylinder provided in the stator slots.

[0024] In the stator laminate 3, at least one set 13 of three first stator partial laminations 3.1 that are twisted in opposite directions about the stator axis 7 is provided to clamp the stator coil 6 at the clamping location 10 of the stator slot 5. With respect to this, two of the first stator partial laminations 3.1 of each set 13 are twisted by a twist angle φ in one circumferential direction about the stator axis 7, and the remaining first stator partial laminations 3.1 of the set 13 are twisted by the twist angle φ in the opposite direction. The thin plates 8 of each first stator partial lamination 3.1 are fixedly coupled to each other, and are particularly bonded, punched and laminated pressed, welded, or baked.

[0025] By the set 13 of the first stator partial laminations 3.1, an axial support region 14 can be formed in the stator laminate 3. In each support region 14 of the stator laminate 3, the stator coils 6 in all the stator slots 5 are locally clamped at the clamping location 10. Each clamping location 10 is an axial region in each stator slot 5. According to this exemplary embodiment, a plurality of, for example, two, three, or four support regions 14 that are axially spaced apart from each other are provided in the stator laminate 3.

[0026] In the stator slot 5 of the stator laminate 3, a protective cylinder 11 is provided in the region of the twisted first stator partial lamination 3.1. The protective cylinder 11 protects the stator coil 6 from damage by the twisted first stator partial lamination 3.1 and is particularly made with electrical insulation.

[0027] According to the present invention, at least one of the protective cylinders 11 has at least one flange portion 12 that is bent relative to the slot section 11.1 of the protective cylinder 11. The flange portion 12 supports the protective cylinder 11 by bracing axially against one of the stator teeth 4 of one of the first stator sub-laminated bodies 3.1 relative to the stator shaft 7, thereby determining the axial position of the protective cylinder 11 within each stator slot 5.

[0028] Within the stator laminate 3, as shown in Figures 2 and 4, there may be at least one second stator sub-laminated laminate 3.2, the second stator sub-laminated laminate 3.2 being positioned between one set 13 of the first stator sub-laminated laminates 3.1 and / or between two sets 13 of the first stator sub-laminated laminates 3.1, and circumferentially, the conductors 15 of the stator coils 6 in each stator slot 5 of the second stator sub-laminated laminate 3.2 are positioned to run along each stator slot 5 with a gap between them and both tooth surfaces 4f of the stator slot 5, thereby forming slot gaps 23 within the stator slots 5. The thin sheets 8 of each second stator sub-laminated laminate 3.2 are fixedly joined to each other, for example, by bonding, punching and laminating press, welding, or baking.

[0029] Each stator slot 5 is permeable to a coolant, particularly oil, along the meandering cooling path 17. The protective cylinder 11 may have bypasses 24 for the flow to bypass the clamping points 10, particularly as recesses or depressions on one of the inner narrow surfaces 22, especially on the inner narrow surface 22 facing or not facing the stator yoke 9.

[0030] A stator sleeve 25 may be provided in the inner diameter of the stator laminate 3 to seal the slot slit 5s. Figure 3 shows a first stator sub-laminated structure based on Figure 2, equipped with a protective cylinder according to the present invention based on a first exemplary embodiment.

[0031] According to the first exemplary embodiment, each protective cylinder 11 extends axially into only one of the first stator sub-laminated 3.1 of a set 13. The flange portion 12 of each protective cylinder 11 is formed on at least one side surface 21 facing the tooth surface 4f of each stator slot 5, and / or on a narrow surface 22 connecting the side surfaces 21.

[0032] Each first stator sub-laminated 3.1 may have at least one end plate 8e on at least one of both end faces, as shown in Figures 2 and 3, the slotted contour of this end plate 8e is offset backward from the remaining plates 8 to form a structural space for accommodating the flange 12 of each protective cylinder 11. In addition, the flange 12 of each protective cylinder 11 may be sandwiched between the plates 8 of the stator laminate 3 in the axial direction with respect to the stator axis 7.

[0033] Figure 4 shows a partial view of the stator according to Figure 1, comprising a plurality of untwisted first stator sub-laminateds, within the stator slots of these first stator sub-laminateds, are protective cylinders according to the present invention according to a second exemplary embodiment.

[0034] According to a second exemplary embodiment, each protective cylinder 11 extends within all of the first stator sub-laminated 3.1 of the set 13, that is, from the flange 12, through all of the first stator sub-laminated 3.1 of the set 13 within each stator slot 5.

[0035] According to a second exemplary embodiment, the flanges 12 of multiple, in particular, all protective cylinders 11 of one or one set 13 of the first stator sub-laminated 3.1 can be integrally connected to form a protective cylinder unit 16. The protective cylinder unit 16 has a plate section 16.1 for connecting the protective cylinders 11. The plate section 16.1 of the protective cylinder unit 16 is located in the plane between two plates 8 of the stator laminate 3.

[0036] The protective cylinder 11 can be formed closed in the circumferential direction according to Figure 5, or interrupted by a slit portion 18 according to Figure 6. According to Figure 6, for example, the slit portion 18 is provided at a corner 19 running axially on the protective cylinder 11.

[0037] The slot section 11.1 of the protective cylinder 11 is formed to correspond to, for example, the shape of the stator slot 5. Therefore, the slot section 11.1 of the protective cylinder 11 can be manufactured with a trapezoidal, rectangular, sleeve-shaped, and partially trapezoidal, partially rectangular, or U-shaped cross-section.

[0038] The protective cylinder 11 may be made from plastic, particularly elastomer or thermoplastic elastomer, or from ceramic. Figure 7 shows a further diagram of the protective cylinder based on Figure 5.

[0039] The protective cylinder 11 may have a radially protruding section 20 on a narrow surface 22 that does not face the stator yoke 9, and this protruding section 20 extends into each slot slit 5s and extends axially.

Claims

1. A stator for an electromachine (2), comprising a stator laminate (3) extending around a stator shaft (7), having stator teeth (4) and stator slots (5) between the stator teeth (4), and comprising stator coils (6) running within the stator slots (5), wherein within the stator laminate (3) there are at least one set (13) of three first stator sub-laminated units (3.1) twisted in opposite directions to clamp the stator coils (6) at clamping locations (10) of the stator slots (5), each Two of the first stator sub-laminated units (3.1) of the set (13) are twisted in one circumferential direction about the stator axis (7), and the remaining first stator sub-laminated units (3.1) of the set (13) are twisted in the opposite direction, and within the stator slot (5) of the stator laminate (3), a protective cylinder (11) is provided in the region of the twisted first stator sub-laminated units (3.1), and the protective cylinder (11) protects the stator coil (6) from damage caused by the twisted first stator sub-laminated units (3.1), and is particularly electrically insulating, in the stator, A stator characterized in that at least one of the protective cylinders (11) has at least one flange (12), the flange (12) is bent with respect to the slot section (11.1) of the protective cylinder (11), and is provided to be supported by axial bracing against one of the stator teeth (4) of one of the first stator partial laminates (3.1).

2. The stator according to claim 1, characterized in that the flange portion (12) of each of the protective cylinders (11) is formed on at least one side surface (21) facing the tooth surface (4f) of each of the stator slots (5), and / or on a narrow surface (22) connecting the side surfaces (21).

3. The stator according to claim 1 or 2, wherein each of the first stator sub-laminated units (3.1) includes at least one end plate (8e) on at least one of both end faces, the slot contour of the end plate (8e) being offset backward from the remaining plates (8) to form a structural space for accommodating the flange (12) of each of the protective tubular units (11), and / or the flange (12) of each of the protective tubular units (11) being sandwiched between the plates (8) of the stator laminate (3).

4. The stator according to any one of claims 1 to 3, characterized in that the flanges (12) of a plurality, in particular all, of protective cylinders (11) of one of the first stator sub-laminated stacks (3.1) or one set (13) of the first stator sub-laminated stacks (3.1) are integrally connected to form a protective cylinder unit (16), the protective cylinder unit (16) having a thin plate section (16.1) for connecting the protective cylinders (11), and the thin plate section (16.1) of the protective cylinder unit (16) is formed in a plane between two thin plates (8) of the stator stack (3).

5. The stator according to any one of claims 1 to 4, characterized in that each of the protective cylinders (11) extends in the axial direction into only one of the first stator sub-laminated bodies (3.1) of each of the sets (13), or into all of the first stator sub-laminated bodies (3.1) of the set (13).

6. The stator according to any one of claims 1 to 5, characterized in that the protective cylinder (11) is formed in a closed manner in the circumferential direction or interrupted by a slit portion (18), and the slit portion (18) is provided in particular at a corner (19) running in the axial direction of the protective cylinder (11).

7. The stator according to any one of claims 1 to 6, characterized in that the slot section (11.1) of the protective cylinder (11) is formed in a cross-section that corresponds to the shape of the stator slot (5), in particular being trapezoidal, rectangular, sleeve-shaped, partially trapezoidal, partially rectangular, or U-shaped.

8. The stator according to any one of claims 1 to 7, characterized in that the material of each of the protective cylinders (11) is plastic, particularly elastomer or thermoplastic elastomer, or ceramic.

9. The stator according to any one of claims 1 to 8, characterized in that the stator teeth (4) are interconnected via a ring-shaped stator yoke (9), and each has a tooth end (4e) formed as a tooth tip, in particular, which does not face the stator yoke (9), the stator slot (5) has a slot slit (5s) formed between each of the tooth ends (4e), and a radially protruding projection section (20) is formed on the narrow surface (22) of each of the protective cylinders (11) that does not face the stator yoke (9), the projection section (20) reaches into each of the slot slits (5s) and extends in the axial direction.

10. The stator according to claim 9, wherein each of the stator slots (5) is passable by a coolant, particularly oil, along the cooling path (17), and in this regard, the protective cylinder (11) is provided with a bypass (24) for the flow to bypass the clamping location (10), particularly on one of the narrow inner surfaces (22) of the protective cylinder (11), and especially on the narrow inner surface (22) that faces or does not face the stator yoke (9).

11. The stator according to any one of claims 1 to 10, wherein at least one second stator sub-laminated (3.2) is provided within the stator laminate (3), the second stator sub-laminated (3.2) is positioned between one set (13) of the first stator sub-laminated (3.1) and / or between two sets (13) of the first stator sub-laminated (3.1), and in the circumferential direction, the conductors (15) of the stator coils (6) in each stator slot (5) of the second stator sub-laminated (3.2) are positioned to run along the stator slot (5) with a gap between both tooth surfaces (4f) of the stator slot (5), thereby forming a slot gap passage (23) within the stator slot (5).

12. An electric machine (2) comprising a stator (1) according to any one of claims 1 to 11.

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