Stator lamination stack and method for manufacturing a stator lamination stack

Abstract

The invention relates to a stator lamination stack with stator laminations, each comprising a stator yoke section and stator tooth sections separated from the stator yoke section, which are integrally connected to each other in tooth root areas. To improve and / or simplify the production of stator lamination stacks, the stator laminations each have at least one manufacturing-optimized predetermined separation point in the tooth root areas.

Description

[0001] The invention relates to a stator lamination stack comprising stator laminations, each of which includes a stator yoke section and stator tooth sections separated from the stator yoke section, which are integrally joined together in tooth root regions. The invention further relates to a method for manufacturing such a stator lamination stack. State of the art

[0002] International Patent Application WO 2012 / 089404 A2 discloses a stator for an electric machine with winding teeth formed from a stack of sheet metal laminations having different geometries. German Patent Application DE 10 2019 114 264 A1 discloses a stator for a brushless DC motor comprising a stator core with a plurality of stacked stator laminations, each having an annular surface and a plurality of stator teeth, wherein the stator teeth are uniformly spaced circumferentially around a longitudinal axis of the stator and each has a tooth root and a tooth tip, wherein currentable windings are arranged on the tooth roots of the stator core to form coils, and wherein the stator core is formed from three different types of stator laminations. Disclosure of the invention

[0003] The object of the invention is to improve and / or simplify the production of stator lamination stacks with stator laminations, each comprising a stator yoke section and stator tooth sections separated from the stator yoke section, which are integrally connected in tooth root areas.

[0004] The problem is solved in a stator lamination stack with stator laminations, each comprising a stator yoke section and stator tooth sections separated from the yoke section and integrally joined at the tooth root, by ensuring that the stator laminations each have at least one manufacturing-optimized predetermined separation point at the tooth root. The separated stator tooth sections of the stator laminations are not connected to the respective stator yoke section. The stator yoke section is, for example, essentially designed as an annular disk-shaped yoke body. The ends of the stator tooth sections facing the stator yoke section are also referred to as head sections. The head sections are not connected to the respective stator yoke section of a stator lamination. The ends of the stator tooth sections facing away from the stator yoke section are also referred to as tooth root sections.At least two tooth root regions of the stator tooth segments of a stator lamination are integrally joined by a manufacturing-optimized separation point. This separation point serves two purposes: firstly, to simplify cutting the integral connection in the tooth root regions, advantageously without compromising the stability of the stator tooth segments to such an extent that further handling of the stator tooth segments during the manufacturing and further processing of the stator lamination stack becomes significantly more difficult; and secondly, the integral connection of the stator tooth segments of a stator lamination in the tooth root regions considerably simplifies the application of windings to the stator teeth, which are represented by the stator tooth segments of a stator lamination stack. The stator yoke sections are advantageously applied to the stator teeth, along with the stator tooth segments of the stacked stator laminations of the stator lamination stack, only after the windings have been applied to the stator teeth.Advantageously, the stator lamination stack is only subsequently overmolded or potted. The integrally connected stator tooth sections represent loose stator root sections within the stator laminations. Depending on the design, all stator tooth sections of a stator lamination can be connected in the tooth root areas by at least one manufacturing-optimized predetermined separation point. According to a further aspect of the invention, the integral connections in the tooth root areas are cut before potting or overmolding. However, the manufacturing-optimized predetermined separation points may eliminate the need for cutting if the stator lamination stack performs its desired function in operation even with the integral connections in the tooth root areas of the stator tooth sections.

[0005] A preferred embodiment of the stator lamination stack is characterized in that the one-piece connection between two circumferentially adjacent stator tooth sections comprises at least two connecting webs spaced apart in a radial direction. The term circumferential direction refers to an axis of rotation of a rotor that is rotatably arranged in the stator to form an electric machine. The term radial also refers to this axis of rotation. A radial distance between the connecting webs is advantageously smaller than the length of the connecting webs, but particularly advantageously larger than the radial dimensions of the connecting webs. The claimed design of the connecting webs simplifies cutting the connecting webs.Furthermore, the connecting webs can also be designed in such a way that cutting is not necessary at all, but the function can still be realized despite the one-piece connections in the tooth root areas of the stator tooth sections.

[0006] Another preferred embodiment of the stator lamination stack is characterized in that the connecting webs have circumferential lengths that are more than twice the radial dimensions of the connecting webs. The connecting webs advantageously have the shape of circular arcs that are spaced apart from one another in the radial direction. The claimed design of the connecting webs allows for a simple way to achieve the desired stability of the stator laminations with the stator tooth sections that are separate or isolated from the respective stator yoke section.

[0007] Another preferred embodiment of the stator lamination stack is characterized in that the stator laminations in the stack each have a number of predetermined separation points that is less than the number of stator tooth segments per stator lamination. A stator lamination stack advantageously comprises at least as many stator laminations as stator teeth. At least two stator tooth segments of a stator lamination are integrally joined at their tooth root regions. Depending on the embodiment, more than two stator tooth segments of a stator lamination can also be integrally joined at their tooth root regions. From a manufacturing perspective, it has proven advantageous if not all stator tooth segments of a stator lamination are integrally joined at their tooth root regions. This offers, among other advantages, the benefit that cutting at these points is unnecessary.

[0008] Another preferred embodiment of the stator lamination stack is characterized in that two stator laminations stacked one above the other in a stator lamination stack have two predetermined separation points which are arranged circumferentially offset from each other by a defined angle. In this way, the desired stability of the stator lamination stack can be achieved with simple means, without having to integrally join all stator tooth sections of the respective stator lamination.

[0009] In a method for manufacturing a previously described stator lamination stack, the above-mentioned problem is solved alternatively or additionally by cutting the one-piece connection in the tooth root regions between two circumferentially adjacent stator tooth sections. Cutting the one-piece connections in the tooth root regions is significantly simplified by the claimed embodiment of the optimized predetermined separation point. The cutting preferably takes place before overmolding or potting the stator laminations in the tooth root regions. Depending on the method, the stator laminations in the tooth tip regions and in the tooth yoke sections can also be potted or overmolden before cutting the predetermined separation points.

[0010] A preferred embodiment of the method is characterized in that loose stator base parts, each comprising at least two stator tooth sections integrally connected at the tooth root, are positioned with their predetermined separation points offset from one another in the circumferential direction by means of a force-fit, material-fit, and / or friction-fit method. The offset positioning of the loose stator base parts can advantageously be carried out directly in a tool, in particular directly in a stamping tool used for manufacturing the stator laminations. Stamping of the stator base parts can also advantageously be carried out directly in the stamping tool. In this way, a stator iron assembly with the claimed stator lamination stack can be manufactured with maximum efficiency.

[0011] Another preferred embodiment of the method is characterized in that the one-piece connections are cut at the predetermined separation points after the stator yoke sections have been assembled. This reduces undesirable losses during the operation of a stator equipped with a stator lamination stack in an electric machine.

[0012] Another preferred embodiment of the method is characterized in that a thermal microstructure transformation takes place in the area of ​​the intended separation points after the stator yoke sections have been assembled. The thermal microstructure transformation can be achieved, for example, using a laser or local heating by induction. This thermal microstructure transformation further reduces operating losses of the stator equipped with the stator lamination stack.

[0013] The invention further relates to a stator lamination and / or a loose stator base section for a previously described stator lamination stack. The stator laminations and the loose stator base sections are separately tradable.

[0014] The invention may also relate to a stator with a previously described stator lamination stack.

[0015] The invention may also relate to an electrically driven compressor with a stator containing a stator lamination stack as previously described.

[0016] Further advantages, features and details of the invention will become apparent from the following description, in which various embodiments are described in detail with reference to the drawing. Brief description of the drawing

[0017] They show: Fig. Figure 1 shows an electric machine with a multi-part rotor shaft in longitudinal section; Fig. 2 a stator lamination with manufacturing-optimized predetermined separation points between circumferentially adjacent tooth sections in a top view; Fig. 3 an enlarged section with a predetermined separation point made of Fig. 2; and Fig. 4 a perspective partial view of a stator lamination stack with stator laminations, as shown in Fig. 2 are shown. Description of the exemplary implementations

[0018] In Fig. Figure 1 shows a gas supply device designed as an electrically driven turbomachine 1, comprising a compressor wheel 2 and a turbine wheel 4, in longitudinal section. The compressor wheel 2 is arranged on a compressor side 3 of the turbomachine 1. The turbine wheel 4 is arranged on a turbine side 5 of the turbomachine 1.

[0019] The turbine wheel 4 is driven by the compressor wheel 2. The two wheels 2 and 4 belong to a rotating assembly 6. The rotating assembly 6 includes a motor shaft 7 to provide a rotationally fixed connection between the compressor wheel 2 and the turbine wheel 4. The motor shaft 7 is partially designed as a hollow shaft and is rotatable about a pivot axis 8.

[0020] For electric drive, the turbomachine 1 comprises an electric machine 9. The electric machine 9 is designed as an electric motor with a motor housing 10 and a motor winding 11. A magnet 12, designed as a permanent magnet, is arranged in the motor shaft 7, which is designed as a hollow shaft.

[0021] In operation within a fuel cell system, the compressor wheel 2 of the turbomachine 1 is driven firstly by the turbine wheel 4. Secondly, the compressor wheel 2 is driven by the electric motor 9.

[0022] The drive unit 6 with the motor shaft 7 is rotatably mounted in the motor housing 10 of the electric machine 9 by means of two radial bearings 13, 14. The radial bearings 13, 14 are advantageously designed as foil air bearings.

[0023] On compressor side 3, a compressor spiral casing 15 is attached to the motor housing 10. The compressor spiral casing 15 includes a compressor inlet 16, through which air to be compressed is supplied to the turbomachine 1.

[0024] On turbine side 5, a turbine spiral casing 17 is attached to the motor housing 10. The turbine spiral casing 17 includes a turbine outlet 18 through which expanded air exits. The energy generated during the expansion of the air is used to drive the compressor wheel 2.

[0025] The motor shaft 7 can also be called a rotor shaft because it serves to form a rotor 19 in the electric machine 9. The rotor 19 comprises a magnetic section 20 in which the magnet 12 is arranged. Two shaft sections 21, 22 are attached to the opposite ends of the magnetic section 20. The magnet 12 is surrounded in the magnetic section 20 by a bandage 23, which can also be called a sleeve.

[0026] In the Fig. 2, Fig. 3 to Fig. Figure 4 illustrates how to use stator laminations 40, one of which is in Fig. 2 is shown in top view, a in Fig. 4. Stator lamination stack 50, shown in perspective, is manufactured. The in Fig. The stator lamination 40 shown in Figure 1 can be manufactured in different versions in the diagram shown in Figure 1. Fig. The stator lamination stack 50 shown in section 4 can be used.

[0027] The in Fig. The stator lamination 40 shown in Figure 2 comprises a stator yoke section 30, which essentially has the shape of a circular annular disk. Stator tooth sections 41 and 42 are arranged radially within the stator yoke section 30. Fig. 2 are, by way of example, twelve stator tooth sections 41, 42 arranged radially within the stator yoke section 30.

[0028] Divided by dividing lines 35, 36, in Fig. Figure 2 indicates that the stator tooth sections 41 and 42 are designed separately from the stator yoke section 30. "Separate" or "separate" in this context means that the stator tooth sections 41 and 42 are designed as separate parts; in particular, the stator tooth sections 41 and 42 are not integrally connected to the stator yoke section 30. Nevertheless, the stator lamination 40 is referred to as the stator lamination.

[0029] The dividing lines 35, 36 are between stator head sections that are in Fig. 2 are not provided with reference numerals, and the stator yoke section 30 is provided. Tooth root regions 43, 44 are arranged at the radially inwardly directed ends of the stator tooth sections 41, 42. The tooth root regions 43, 44 of the stator tooth sections 41, 42 are integrally connected to each other by a one-piece connection 71.

[0030] In Fig. Figure 3 shows an enlarged top view of the two integrally connected stator tooth sections 41, 42 with the integral connection 71. The two integrally connected stator tooth sections 41, 42 constitute a loose stator base part 45 that can be handled separately.

[0031] This loose stator base part 45 can be combined in different configurations with other loose stator base parts in a stator lamination 40, as shown in Fig. The figures shown in section 2 can be combined. Fig. 2 indicates that the one-piece connection 71 is combined with a predetermined separation point 73.

[0032] Another one-piece connection 70 is in Fig. 2 are arranged diametrically opposite the one-piece connection 71. The one-piece connection 70 also connects two unspecified stator tooth sections. Furthermore, the one-piece connection 70 is also combined with a predetermined separation point 75.

[0033] Depending on the design, more than two stator tooth sections, for example three or more stator tooth sections, can be connected to each other in one piece by means of one-piece connections with predetermined separation points.

[0034] In Fig. Figure 3 shows that the one-piece connection 71 between the two tooth root regions 43, 44 of the stator tooth sections 41, 42 comprises two connecting webs 31, 32, which are spaced apart from each other in the radial direction. The two radially spaced connecting webs 31, 32 represent the predetermined separation point 73 of the one-piece connection 71.

[0035] The connecting webs 31, 32, for example, have the same thickness as the stator tooth sections 41, 42. In the radial direction, the connecting webs 31, 32 have a significantly smaller dimension than in the circumferential direction.

[0036] In Fig. Figure 4 shows a circumferential direction 61, a radial direction 62, and a stacking direction 63 indicated by arrows. The circumferential direction 61 and the radial direction 62 refer to an axis of rotation of a rotor that is rotatable within a stator, which is constructed using stator lamination stacks 50, as shown in Fig. The stacking direction 63, as shown in Figure 4, is realized. The stacking direction 63 extends parallel to this axis of rotation.

[0037] A multitude of stator laminations 40 stacked one above the other in the stacking direction 63 serve to form stator teeth 51 to 54, which are wound with winding wires in a known manner. Further stator tooth sections are provided with reference numerals 55 to 58 in the stator lamination stack 50. The stator tooth sections 55 to 58 are similar to those described in Fig. 2 is indicated, connected to each other by one-piece connections which are provided with predetermined separation points 73, 74.

[0038] In Fig. 2 is indicated in a reduced detail by an angle 77, that the stator laminations 40 or loose stator base parts 45, as in one in Fig. 3 is shown, rotated relative to each other to align the stator lamination stack 50 in Fig. 4 to represent.

[0039] In Fig.Figure 4 indicates how different stator base parts 45, 46 can be combined with each other in the stator lamination stack 50 by means of a further one-piece connection 72 with a predetermined separation point 74. The loose stator base parts 45, 46 represent partial connections in the area of ​​the tooth roots of the stator tooth sections and can be arranged offset from each other in a stamping tool, for example by an angle 77.

[0040] The offset positioning of the stator base parts 45, 46 is maintained in the tool even without a connection between the loose stator base parts 45, 46 for a short time. A stamping process can ensure that the positioning is permanent in order to represent a stator iron core.

[0041] Without the stator yoke section 30, the winding can then be inserted from the outside. The yoke sections are then advantageously mounted. The stator assembly can then be overmolded. Optionally, after the yoke is mounted, the partial connection can be removed by cutting the one-piece connections at the designated separation points. 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] WO 2012 / 089404 A2

[0002] DE 10 2019 114 264 A1

[0002]

Claims

Stator lamination stack (50) with stator laminations (40), each comprising a stator yoke section (30) and stator tooth sections (41, 42; 55, 56, 57, 58) separated from the stator yoke section (30), which are integrally connected to each other in tooth root regions (43, 44), characterized in that the stator laminations (40) each have at least one manufacturing-optimized predetermined separation point (73, 74, 75) in the tooth root regions (43, 44). Stator lamination stack (50) according to claim 1, characterized in that the one-piece connection (71) between two stator tooth sections (41, 42) adjacent in a circumferential direction (61) comprises at least two connecting webs (31, 32) spaced apart from each other in a radial direction (62). Stator lamination stack (50) according to claim 2, characterized in that the connecting webs (31, 32) have circumferential lengths that are more than twice as large as radial dimensions of the connecting webs (31, 32). Stator lamination stack (50) according to one of the preceding claims, characterized in that the stator laminations (40) in the stator lamination stack (50) each have a number of predetermined separation points (73, 74, 75) which is less than a number of teeth of stator tooth sections (41, 42; 55, 56, 57, 58) per stator lamination (40). Stator lamination stack (50) according to one of the preceding claims, characterized in that two stator laminations (40) stacked one above the other in a stator lamination stack (50) have two predetermined separation points (73, 74, 75) which are arranged in the stator lamination stack (50) offset from each other in the circumferential direction (61) by a defined angle (77). Method for manufacturing a stator lamination stack (50) according to one of the preceding claims, characterized in that the one-piece connection (71) in the tooth root areas (43,44) between two circumferentially adjacent stator tooth sections (41,42;55,56,57,58) is cut. Method according to claim 6, characterized in that loose stator foot parts (45), each comprising at least two stator tooth sections (41, 42) integrally connected in the tooth foot regions (43, 44), are positioned relative to each other by means of a force-, material-, and / or friction-locking method with their predetermined separation points (73) offset in the circumferential direction (61). Method according to one of claims 6 or 7, characterized in that the cutting of the one-piece connections (71) at the predetermined cutting points (73, 74, 75) takes place after assembly of the stator yoke sections (30). Method according to claim 8, characterized in that a thermal microstructure transformation takes place in the area of ​​the intended separation points (73, 74, 75) after the assembly of the stator yoke sections (30). Stator lamination (40) for a stator lamination stack (50) according to one of claims 1 to 5 .

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