WO2023061737A1

WO2023061737A1 - Slot liner for a rotor or stator of an electric machine

Info

Publication number: WO2023061737A1
Application number: PCT/EP2022/076672
Authority: WO
Inventors: Alexander Chugreev
Original assignee: Robert Bosch Gmbh
Priority date: 2021-10-11
Filing date: 2022-09-26
Publication date: 2023-04-20

Abstract

The invention relates to a slot liner (15) for a rotor (1) and/or stator (1) of an electric machine (2). The slot liner (15) consists of a folded flat insulating material (16), and the flat insulating material (16) is folded such that in a state in which the flat insulating material (16) lines a slot (4) of the rotor (1) or the stator (1), a contact of the flat insulating material (16) on multiple faces (5, 6, 7, 8) of the slot (4) of the rotor (1) or the stator (1) is facilitated, and at least one projection (17) is formed on the flat insulating material (16), said projection protruding out of the slot (4) on one end face (18) of the rotor (1) or the stator (1) in the aforementioned state. According to the invention, at least one paper tongue (19) is cut onto the projection (17), and the paper tongue (19) is folded over onto the end face (18) of the rotor (1) or the stator (1) in the aforementioned state. The invention additionally relates to an electric machine (2) and a rotor (1) or a stator (1) comprising such slot liners (15).

Description

title

Slot lining for a rotor or stator of an electrical machine

State of the art

The invention relates to a slot lining for a rotor and/or stator of an electrical machine, a component of an electrical machine and an electrical machine.

A slot lining for a stator using insulating paper is known from US Pat. No. 3,514,836. Here, the insulating paper is folded with two creases at two edges along the extension of a groove into which the insulating paper is inserted. In addition, when the insulating paper is inserted into the slot, it protrudes slightly at the end face of the stator, so that there is an overhang around the three sides. The overhang is designed as a support collar that is bent over on the three sides.

The slot lining known from US Pat. No. 3,514,836 has the disadvantage that the insulating paper bulges out when it is inserted, making it more difficult to insert the electrical conductors into the lined slot. In addition, the inserted insulating papers overlap from one slot to the next, which is unfavorable.

In the production of a stator of an electrical machine, the wiring of the stator winding can be carried out using methods from the group of plug-in technology, in which case solid copper conductors can be used as winding elements, which can be in the form of pins. The winding elements are inserted into the laminations of the stator by axial feeding. Before joining, the stator slots are lined with a surface insulating material. When assembling or joining the copper winding in the Laminate pack with the surface insulation material in the stator slots, the surface insulation material can then slip through due to the coefficients of friction and narrow tolerances, which are caused in particular by a desired copper fill factor. The surface insulating material can be a multi-layer laminate, for example a two-layer laminate.

In order to avoid slipping through, a surface insulating material, in particular insulating paper, with a support collar can be used in the known process chains. The collar has a supporting function to ensure the axial position of the surface insulation when joining the wires. However, such a support collar can be undesirable in the respective application and/or cause disadvantages. However, the omission of the support collar leads to an unstable process due to the possible slipping through of the surface insulating material.

Disclosure of Invention

The slot lining according to the invention with the features of claim 1, the component according to the invention with the features of claim 8 and the electrical machine according to the invention with the features of claim 10 have the advantage that an improved design and mode of operation are made possible.

Advantageous developments of the slot lining specified in claim 1, the component specified in claim 8 and the electrical machine specified in claim 10 are possible as a result of the measures listed in the dependent claims.

The component of the electrical machine can be a rotor or a stator of the electrical machine. The proposed slot linings can also be provided both on the rotor and on the stator. Furthermore, the proposed slot linings are preferably provided on all slots of the rotor or on all slots of the rotor.

The proposed slot lining and the proposed rotor or the proposed stator are particularly suitable for one electric drive motor for motor vehicles. In this way, traction and support drives can be implemented, in particular with plug-in technology for the high and low voltage range.

An incision is advantageously made on the sheet insulating material to form the paper tongue which can be used to secure the paper position. In the case of a stator, the incision is preferably made on the preferably radially outer side of the flat insulating material during folding. During or after the joining of the surface insulating material, a type of tongue or tab can be bent to the side by a preferably axial expansion of the paper and clamped by a single clamping mask on the periphery of the laminated core.

This keeps the surface insulating materials in their positions. In this way, the copper elements can be inserted into the laminated core without a surface insulating material slipping through or a support collar being required. Since the surface insulating material may not have to take on an insulating function, since this already exists through an insulating coating of the copper elements, and can therefore only be used to join the wire basket without damage, the electrical function of the machine is not impaired.

The depth, number and shape of the incision can be varied. Furthermore, other modifications can also be realized.

The tension mask can be executed as an iris tool analogous to a support finger tool. This can only hold the surface insulation material axially when the wiring unit is joined into the lamina stack. It is advantageous if these clamping surfaces for the surface insulating materials can be integrated into existing iris tools with support fingers, so that comparatively low tool costs then arise. A clamping device to hold the slot linings in place is usually required during production. After the wiring unit has been added to the plate pack, the clamping device then moves out. It therefore does not remain on the product. However, the paper tabs can remain on the product.

The paper tongues can then subsequently be processed without changing the process chain held in place by impregnating resin. The surface insulating materials with cut edges can also only be over-resinized.

It is advantageous that the paper tongue is cut through at least one cut that extends at least approximately along a fold edge of the surface insulating material. The at least one cut can advantageously be made during the preparation of the planar insulating material, in particular after folding.

It is advantageous that the paper tongue is cut through at least one further cut, which extends at least approximately along a further folded edge of the flat insulating material, and that the folded edge of the flat insulating material and the further folded edge of the flat insulating material extend along a longitudinal direction of the flat insulating material, which in the mentioned State is oriented at least approximately parallel to an axis of rotation of the electrical machine. As a result, the paper tongue can advantageously be designed in the form of a tab, which can then be placed against the end face. In this case, the paper tongue can be folded over in an area where the surface insulating material emerges from the groove at the end face in the state mentioned, in which the surface insulating material lines a slot of the rotor or the stator. This kink can already be realized when preparing the surface insulating material.

It is advantageous that the folded edge of the flat insulating material and the further folded edge of the flat insulating material are arranged in the mentioned state on edges of the slot of the stator or the rotor, between which lies a narrow side of the slot and/or the side of the slot lying on the stator yoke or on the rotor yoke. As a result, the paper tongue can be designed at least largely flat and free of folded edges and also optimally wide, so that the slot lining is advantageously prevented from slipping through when the electrical conductors are joined into the slot.

It is advantageous that the paper tongue is folded over towards the stator yoke or towards the rotor yoke. In this way, an advantageous arrangement can be implemented. In particular, there is usually more space towards the yoke than towards the tooth. In addition, the groove can be partially open towards the tooth, so that the Contact surface on the front side would therefore also be reduced. Furthermore, there is usually a comparatively small distance between adjacent grooves, so that the paper tab would then have to be shortened if necessary. An arrangement of the paper tongue toward the yoke is therefore generally preferred.

It is advantageous that the planar insulating material is widened at the overhang, in particular is widened at least approximately in the shape of a truncated pyramid. This can facilitate the insertion of the electrical conductors into the slot lined with the slot liner.

It is advantageous that the surface insulating material has a transverse cut between at least two edges, between which no paper tongue is cut, which in the state mentioned is preferably arranged at least approximately in the vicinity of the end face of the rotor or the stator, and that the transverse cut Section preferably runs at least substantially from one of the two edges to the other of the two edges. This makes it easier to insert the electrical conductors into the slot lined with the slot lining.

It is advantageous that a resin coating is provided and that the paper tongue of the surface insulating material is held in place by the resin coating on the end face of the rotor or stator. This enables an advantageous fixation of the paper tongue in the manufactured state, so that in particular a subsequent shortening of the paper tongue can be omitted.

It is thus possible to implement a process-reliable and cost-effective slot lining without a support collar for rotors and/or stators, which is particularly suitable for rod technology with electrical conductors that can be designed in the shape of a hairpin.

Short descriptions of the drawings

Preferred embodiments of the invention are in the following description with reference to the accompanying drawings in which Corresponding elements are provided with the same reference numerals, explained in more detail. Show it:

1 shows a component of the electrical machine, which is designed as a rotor or stator of an electrical machine, according to a first exemplary embodiment in a partial, schematic representation during manufacture;

FIG. 2 shows the component shown in FIG. 1 according to the first exemplary embodiment during manufacture, with a slot liner being inserted into a slot;

Figure 3 shows the component shown in Figure 1 according to the first embodiment, with the slot liner and electrical conductors inserted into the slot;

4 shows a component, which is designed as a stator of an electrical machine, according to a second exemplary embodiment in a partial, schematic, spatial representation during production, with a slot lining being inserted into a slot;

5 shows a component, which is designed as a rotor or stator of an electrical machine, according to a third exemplary embodiment in a partial, schematic representation during production, with a slot lining being inserted in a slot;

FIG. 6 shows the component shown in FIG. 5 according to the third exemplary embodiment in a partial, schematic, three-dimensional representation during production, with the slot lining being inserted into the slot; and

7 shows the slot lining shown in FIG. 6 according to the third exemplary embodiment in a schematic representation from the viewing direction labeled VII.

Embodiments of the invention 1 shows a component 1 of the electrical machine, which is designed as a rotor or stator of an electrical machine 2, according to a first exemplary embodiment in a partial, schematic representation during production. The component 1 has a multiplicity of lamellae 3, of which only the lamella 3 is identified to simplify the illustration.

The component 1 has a groove 4 . Furthermore, the component 1 has further grooves 4 which are designed in accordance with the groove 4 . The groove 4 includes sides 5, 6, 7, 8 (Fig. 4). On the side 7 the groove 4 is open towards a lateral surface 9 of the component 1 .

FIG. 2 shows the component 1 shown in FIG. 1 according to the first exemplary embodiment during production. Here, a slot liner 15 is inserted into the slot 4 . The slot lining 15 is folded from a surface insulating material 16. In this exemplary embodiment, the surface insulating material 16 is in the form of insulating paper 16 .

The concept of surface insulating material 16 is to be understood in general terms and includes papers, laminates, which can have a foil and/or pressboard, foils and slot insulation.

This is done when preparing the slot liner 15. The insulating paper 16 is then folded so that in a state where the insulating paper 16 is inserted into the slot 4 of the component 1 and lines it, the insulating paper 16 is then folded on the multiple sides 5, 6, 7, 8 (Fig. 4) of the groove 4 rests.

The insulating paper 16 is cut to such a large size and is arranged in the groove 4 in such a way that an overhang 17 is formed on the insulating paper 16 which protrudes from the groove 4 on an end face 18 of the component 1 . Furthermore, the groove lining 15 is prepared in such a way that a paper tongue 19 is cut into the overhang 17 . When the groove liner 15 is then inserted into the groove 4, the paper tongue 19 is placed against the face 18. The paper tongue 19 is cut through a cut 20 and a further cut 21 . Here, the cut 20 extends along a folded edge 22 of the insulating paper 16. The further cut 21 extends along a further folded edge 23 (Fig. 4) of the insulating paper 16. Since the folded edges 22, 23 and further folded edges 24, 25 along a longitudinal direction 27 of the insulating paper 16 or the slot lining 15, the cuts 20, 21 then also extend along the longitudinal direction 27. Since the slot 4 extends parallel to an axis of rotation of the electrical machine through the component 1, the longitudinal direction 27 of the slot lining 15 is in the Mentioned state oriented parallel to the axis of rotation of the electrical machine 2.

When the slot liner 15 is placed in the slot 4, the folding edges 22, 23, 24, 25 of the insulating paper 16 lie against edges 28, 29 (Fig. 4), 30 (Fig. 4), 31 of the slot 4. Here are the folded edges 22, 23 are arranged on the edges 28, 29, between which a narrow side 5 of the groove 4 lies. This side 5 then lies on the stator yoke 32 or on the rotor yoke 32 depending on the design of the component 1 as a stator 1 or rotor 1 .

FIG. 3 shows the component 1 shown in FIG. 1 according to the first exemplary embodiment. In this case, as in FIG. 2 , the slot lining 15 is inserted into the slot 4 . Furthermore, electrical conductors 35 are inserted into the groove 4, which are shown in a greatly simplified form. The electrical conductors 35 are joined along the longitudinal direction 27 through the slot 4 lined with the slot lining 15 . Here, the groove lining 15 is held stationary relative to the lamellae 3 and is not pulled through the groove 4 since the groove lining 15 is sufficiently fixed by its paper tongue 19 resting on the end face 18 .

After the insertion of the electrical conductors 35, a resin coating 40 is applied. The paper tongue 19 of the insulating paper 16 is then attached to the face 18 of the component 1 by the resin coating 40 . The resin coating 40 can be applied by immersion or by dripping. The insulating paper 16 can absorb the impregnating resin. FIG. 4 shows the component 1, which is designed as a stator 1 of an electrical machine 2, according to a second exemplary embodiment in a partial, schematic, three-dimensional representation during production. Here, a slot liner 15 is inserted into the slot 4 . In this exemplary embodiment, the insulating paper 16 is widened at the overhang 17. The widening is in the form of a truncated pyramid.

5 and 7 illustrate a configuration according to a third embodiment. Here, FIG. 5 shows a component 1, which is designed as a rotor 1 or stator 1 of an electrical machine 2, according to the third exemplary embodiment in a partial, schematic representation during manufacture. FIG. 6 shows the component 1 according to the third exemplary embodiment in a partial, schematic, three-dimensional representation during production. FIG. 7 shows the slot lining 15 shown in FIG. 6 according to the third exemplary embodiment in a schematic representation from the viewing direction labeled VII. Here, the slot liner 15 is inserted into the slot 4 in Fig. 5 and 6.

The insulating paper 16 has the folded edges 22, 23, 24, 25. Between the two adjacent folding edges 22, 25, a transverse cut 41 is provided. The cut 41 is preferably made on the insulating paper 16 in such a way that it is arranged at least approximately in the vicinity of the end face 18 of the component 1 . In addition, the transverse cut 41 preferably runs at least substantially from one edge 22 to the other edge 25.

A transverse cut 42 is provided between the two adjacent folded edges 23, 24 in a corresponding manner. The cut 42 is preferably made on the insulating paper 16 in such a way that it is arranged at least approximately in the vicinity of the end face 18 of the component 1 . In addition, the transverse cut 42 preferably runs at least substantially from one edge 23 to the other edge 24.

As illustrated in FIG. 7, bulges 43, 44 of the insulating paper 16, which are located outside the groove 4, can thus be made possible. This makes it easier to insert the electrical conductors 35 into the slot 4 lined with the slot lining 15 .

The paper tongue 19 is preferably not shortened. But it can be shortened. The remaining overhang 17 can be shortened to a few millimeters, for example, in the respective application.

The invention is not limited to the exemplary embodiments described.

Claims

Expectations

1. Slot lining (15) for a rotor (1) and/or stator (1) of an electrical machine (2), the slot lining (15) being folded from a flat insulating material (16), the flat insulating material (16) being folded in this way that in a state in which the surface insulating material (16) lines a slot (4) of the rotor (1) or the stator (1), the surface insulating material (16) rests on several sides (5, 6, 7, 8) of the groove (4) of the rotor (1) or of the stator (1) is made possible, and wherein at least one projection (17) is formed on the surface insulating material (16), which in the stated state is on an end face (18) of the rotor (1 ) or the stator (1) protrudes from the groove (4), characterized in that at least one paper tongue (19) is cut into the projection (17) and that the paper tongue (19) in the stated state is attached to the end face (18) of the Rotor (1) or the stator (1) is folded.

2. Slot lining according to claim 1, characterized in that the paper tongue (19) is cut through at least one cut (20) which extends at least approximately along a folded edge (22) of the surface insulating material (16).

3. Slot lining according to claim 2, characterized in that the paper tongue (19) is cut through at least one further cut (21) which extends at least approximately along a further fold edge (23) of the surface insulating material (16), and that the fold edge (22) of the flat insulating material (16) and the further folded edge (23) of the flat insulating material (16) extend along a longitudinal direction (27) of the flat insulating material (16), which in the stated state is oriented at least approximately parallel to an axis of rotation of the electrical machine (2). is.

4. slot lining according to claim 3, characterized in that that the folded edge (22) of the flat insulating material (16) and the further folded edge (23) of the flat insulating material (16) in the stated state on edges (28, 29) of the slot (4) of the stator (1) or of the rotor (1) are arranged, between which lies a narrow side (5) of the groove (4) and/or on the stator yoke (32) or on the rotor yoke (32).

5. Slot lining according to one of claims 1 to 4, characterized in that the paper tongue (19) is folded towards the stator yoke (32) or towards the rotor yoke (32).

6. slot lining according to one of claims 1 to 5, characterized in that the surface insulating material (16) at the projection (17) is widened, in particular at least approximately widened in the shape of a truncated pyramid.

7. Slot lining according to one of Claims 1 to 6, characterized in that the surface insulating material (16) has a transverse cut (41 ; 42), which in the state mentioned is preferably arranged at least approximately in the vicinity of the end face (18) of the rotor (1) or the stator (1), and that the transverse cut (41 ; 42) is preferably at least essentially one of the two edges (22; 23) extends to the other of the two edges (25; 24).

8. Component (1) of an electrical machine (2), in particular a rotor (1) or stator (1), the component (1) having a plurality of slots (4) lined with slot linings (15), characterized in that the slot liners (15) are each formed according to any one of claims 1 to 7.

9. Component according to claim 8, characterized in that that a resin coating (40) is provided and that the paper tongue (19) of the surface insulating material (16) is held in place by the resin coating (40) on the end face (18) of the rotor (1) or stator (1).

10. Electrical machine (2) with a rotor (1), which is designed according to claim 8 or 9, and / or a stator (1), which is designed according to one of claims 8 or 9.