DE102020111815A1 - Rotor and method for manufacturing a rotor - Google Patents

Abstract

A rotor for a current-excited synchronous machine, comprising a laminated core with a winding, the laminated core extending along a rotor axis, wherein a cover element is arranged at least at a first end of the laminated core, which forms or forms an arrangement space towards the laminated core, wherein the arrangement space at least is partially filled with a first material, in particular a potting material, and wherein at least one material section is arranged in the arrangement space, which in cooperation with the first material forms an additional element made of a composite material.

Description

The present invention relates to a rotor, a motor series, an electrical machine and a method for manufacturing a rotor.

For the mechanical stabilization of rotor windings, the rotors are often encapsulated or encapsulated with a casting compound. the DE 10 2016 205 813 A1 discloses, for example, a method for the production of a rotor, a laminated rotor core and winding being placed in a casting mold and encapsulated with a plastic compound. It has been shown that cracks can form in the area of the potting compound. Often, when the potting compound cools down, microcracks occur, which become larger when the rotor is later in operation. This can lead to problems, especially if the crack growth extends to the actual rotor winding. This can lead to wire breaks, especially in the area of the winding heads.

It is therefore an object of the present invention to specify a rotor, a motor series, an electrical machine and a method for manufacturing a rotor, which solve the aforementioned problem, with rotors being specified which are characterized by excellent operational stability and are inexpensive to manufacture are.

This object is achieved by a rotor according to claim 1, by a motor series according to claim 9, by an electrical machine according to claim 10 and by a method according to claim 11. Further advantages and features emerge from the subclaims as well as the description and the attached figures.

According to the invention, a rotor for a current-excited synchronous machine comprises a laminated core with a winding, the laminated core being arranged directly or indirectly on a rotor shaft which extends along a rotor axis . Forms or at least forms an arrangement space with this, wherein the arrangement space is at least partially filled with a first material, in particular a potting material, and wherein at least one material section is provided or arranged in the arrangement space, which in cooperation with the first material an additional element forms from a composite material. It has been found that the potting compound can be stabilized and solidified with the additional element, as a result of which any crack formation in the potting compound or in the first material or any crack growth can be effectively countered. The at least one material section is particularly preferably designed to be flexible and / or soft or resilient, as a result of which optimal contact with the first end of the laminated core is possible. In other words, the at least one material section can adapt to the shape of the end winding on which it is arranged or rests. Such a rotor can also be manufactured economically, since the additional element is formed automatically, so to speak, from the composite material when the arrangement space is filled with the first material.

According to a preferred embodiment, the rotor is overmolded or encapsulated, for example in an injection molding tool. Alternatively, potting takes place by means of a potting process, such as vacuum pressure gelling, for example. According to a preferred embodiment, the first material is a thermosetting or thermoplastic material.

According to one embodiment, a multiplicity of material sections, in particular two, three, four or even more, are arranged along the rotor axis for forming the additional element. In other words, the additional element preferably has a layer or layer structure, the individual layers or layers each being formed by a material section. This advantageously makes it possible to provide a scalable additional element, in particular a scalable reinforcement, the scaling being adaptable to set a stiffness of the additional element and / or a thermal capacity which, depending on the engine design, for example with regard to the speeds used or, more generally, the performance class , can be different.

According to one embodiment, the at least one material section or the additional element is designed in the form of a disk. In particular, the at least one material section or the additional element is dimensioned in such a way that the arrangement space is completely or at least approximately completely filled in the radial direction.

According to one embodiment, the at least one material section is a fleece, woven fabric and / or scrim. Multiaxial, quasi-isotropic and / or isotropic materials are preferably used. The at least one material section is preferably formed from a non-metallic material, such as a textile material, a glass material or a carbon material. Alternatively, metallic materials, such as metal mesh, possibly provided with a suitable coating, can also be used.

Typical layer thicknesses are in a range from approximately 0.2 to 3 mm, particularly preferably in a range from approximately 0.3 to 2.5 mm.

According to a preferred embodiment, a glass scrim is used as the scrim, for example, which has a laminate thickness in a range of about 0.3 to 0.4 mm, particularly preferably 0.35 mm in particular. Such a glass fabric advantageously has a +/- 45 ° orientation. A preferred weight per unit area is in a range of 320 g / mm ² . An alternatively preferred glass fabric has a 0/90 ° fiber orientation. The weight per unit area and the layer thickness expediently correspond to the aforementioned dimensions.

According to one embodiment, a fleece or a fleece material is designed as a needle fleece, preferably with a weight per unit area of about 50 g / m ² . Preferred thicknesses for the fleece are in a range from approximately 1 to 2 mm, particularly preferably in a range from approximately 1.5 to 1.8 mm, very particularly preferably around 1.7 mm.

According to one embodiment, the additional element comprises or has a plurality of differently designed and / or oriented material sections.

According to a preferred embodiment, the additional element has a glass scrim with a +/- 45 ° fiber orientation and a further glass scrim with a 0/90 ° fiber orientation and a layer of needle punched nonwoven. According to the preferred embodiment, the additional element is therefore in particular three-layered.

The additional element is expediently scalable, so it can also have more or fewer layers. According to a preferred embodiment, the thickness of the additional element preferably remains constant or the same, as will be explained in more detail below. The thickness is measured along the rotor axis. The constant thickness or wall thickness makes it possible that the design of the reinforcement otherwise does not require any structural changes to the rotor or the electrical machine. This not only reduces the complexity, but also benefits the assembly process, since, for example, a worker or a mechanical device such as an industrial robot, by means of which the at least one material section is arranged, can always work with a component of the same size.

According to one embodiment, the at least one material section or the additional element has an opening which is designed for, in particular a form-fitting, arrangement on the rotor shaft. According to one embodiment, the opening is round, in particular circular. The opening enables secure and fault-free assembly of the at least one material section as well as pre-fixing on the rotor or the rotor shaft. The material section can expediently simply be pushed onto the rotor shaft.

According to one embodiment, the at least one material section has a radially oriented circumferential surface which is angular or non-circular. This geometry expediently enables the at least one material section to be pre-fixed in the arrangement space. This is advantageous with regard to the later overmolding, casting or casting around, since any undesired displacement of the at least one material section can be avoided by the non-round design of the at least one material section. In particular, twisting about the rotor axis is avoided, for example.

According to one embodiment, the at least one material section is fixed or pre-fixed on the cover element by at least one fastening element. According to one embodiment, the at least one material section is fastened to the cover element or in particular to an inside of the cover element, for example by means of an adhesive or adhesive tape, such as in particular by means of a double-sided adhesive tape. A temperature-resistant adhesive or a temperature-resistant adhesive tape is preferably used, a temperature resistance of up to about 200 ° C. having proven to be sufficient.

According to one embodiment, a cover element is also arranged at the second end of the laminated core. Cover elements are preferably arranged at both ends of the laminated core. The basic structure of the rotor is designed in such a way that the laminated core, which is composed of a plurality of individual laminated laminations, in particular stacked, is arranged on the rotor shaft. The laminated core forms a large number of rotor teeth or rotor slots, which are used to arrange the winding. According to a preferred embodiment, so-called star disks or end disks are arranged on the end face of the laminated core and serve, among other things, to guide and fix the winding. The winding is preferably formed by a flexible conductor material, in particular a (copper) wire. The cover elements are arranged on the laminated core or in particular on the star or end disks. This entire arrangement is then placed in a suitable tool for encapsulation, encapsulation or injection molding.

According to a preferred embodiment, the casting compound is introduced via at least one of the cover elements which is designed to be suitable for this purpose, for example by having one or more holes or openings.

According to a preferred embodiment, the contacting of the winding is formed in the area of the first end of the laminated core. In particular, the additional element is thus advantageously formed where a current collector of the rotor is also located, etc. According to one embodiment, an additional element is also formed at the opposite end or alternatively only at the opposite end. Here, too, the cover element forms an arrangement space with a front end of the laminated core.

The invention also relates to a motor series comprising a large number of electrical machines which have rotors according to the invention, the large number of electrical machines differing with regard to at least one parameter, such as in particular the speed and / or power class, and where those arranged in the rotors Additional elements have the same or essentially the same thickness or wall thickness, the layer structure of the additional elements being different. The composition of the additional element can therefore expediently be varied or scaled. For rotors in electric motors with low power / speed, the additional element consists, for example, only of a fleece. For rotors in electric motors with higher power / speed, the additional element expediently consists to a greater percentage or proportion of multiaxial, quasi-isotropic or isotropic fabric or scrim, in particular glass fabric. In addition to reducing costs, the scalability enables the use of the same filling volumes at all times.

The invention is also directed to an electrical machine, in particular a current-excited synchronous machine. The electrical machine is preferably designed as a traction motor for a partially or fully electrified motor vehicle, in particular a passenger car, a motorcycle or a utility vehicle.

• - Bereitstellen eines Blechpakets mit einer Wicklung;
• - Bereitstellen eines Deckelelements zur Anordnung an einem ersten Ende des Blechpakets, wobei zwischen dem ersten Ende des Blechpakets und dem Deckelelement ein Anordnungsraum gebildet wird;
• - Anordnen zumindest eines Materialabschnitts am Rotor oder am Deckelelement;
• - Anordnen des Deckelelements an dem ersten Ende des Rotors;
• - Vergießen oder Umgießen des Blechpakets mit einem ersten Material, insbesondere einer Vergussmasse, sodass im Zusammenwirken mit dem zumindest einen Materialabschnitt ein Zusatzelement aus einem Verbundmaterial geformt wird.

The invention further relates to a method for producing a rotor for a current-excited synchronous machine, comprising the steps:

• - Provision of a laminated core with a winding;
• - Provision of a cover element for arrangement at a first end of the laminated core, an arrangement space being formed between the first end of the laminated core and the cover element;
• - Arranging at least one material section on the rotor or on the cover element;
• Arranging the cover element on the first end of the rotor;
• Potting or casting around the laminated core with a first material, in particular a potting compound, so that an additional element is formed from a composite material in cooperation with the at least one material section.

At this point it should be mentioned that the advantages and features mentioned in connection with the rotor, the motor series or the electrical machine apply analogously or correspondingly to the method, and vice versa.

• - Befestigen des zumindest einen Materialabschnitts am Deckelelement;
• - Anordnen des Deckelelements am Rotor.

According to one embodiment, the method comprises the steps:

• - Fastening the at least one material section on the cover element;
• - Arranging the cover element on the rotor.

This advantageously ensures that a rotor with reinforcement or with at least one additional element cannot be manufactured differently than a rotor without.

• - Umgießen, Umspritzen oder Vergießen über das Deckelelement, welches hierzu zumindest eine Öffnung zum Einbringen des ersten Materials aufweist.

According to one embodiment, the method comprises the step:

• Encapsulation, encapsulation or encapsulation over the cover element, which for this purpose has at least one opening for introducing the first material.

The cover element or elements advantageously act as a mold for the potting compound or the first material, that is to say in particular form a cavity for the first material. The cover element or elements are expediently arranged in a form-fitting and / or force-fitting manner on the rotor shaft and / or on the laminated core or, in particular, on the star or end disks arranged there. According to one embodiment, the arrangement takes place, for example, via a suitably designed bayonet lock. The arrangement space is expediently tightly closed when the cover element is completely arranged, apart from only the aforementioned openings or holes for introducing the potting compound.

Further advantages and features emerge from the following description of embodiments of rotors with reference to the attached figures.

• 1: eine schematische Teilansicht eines Rotors mit einem dreilagigen Zusatzelement;
• 2: eine weitere schematische Teilansicht eines Rotors mit einem einlagigen Zusatzelement;
• 3: eine Ausführungsform eines Rotors entlang einer Rotorachse gesehen.

Show it:

• 1 : a schematic partial view of a rotor with a three-layer additional element;
• 2 : Another schematic partial view of a rotor with a single-layer additional element;
• 3 : an embodiment of a rotor seen along a rotor axis.

1 shows a rotor in a schematic view 10 , comprising a laminated core 14th , which is formed from a large number of individual sheet metal lamellas. The sheet metal lamellas are not shown here. The sheet metal package 14th is on a rotor shaft 12th arranged, which is along a rotor axis R. extends. On the face of the laminated core 14th is a faceplate 16 arranged, this serving in particular for the arrangement and guidance of a winding, which is not shown here in detail. However, a winding head is indicated schematically 20th the winding. Opposite the laminated core 14th is on the front disk 16 a cover element 30th arranged, this being a forehead area 32 as well as a circumferential or envelope area 34 includes. The cover element 30th forms together with the end disk 16 an arrangement space A. . Between the winding head 20th as well as the forehead area 32 of the cover element 30th is an additional element 40 formed, which in the embodiment shown here, three material sections 42 includes. According to one embodiment, for example, is the left material section 42 formed from a needle fleece, while the two material sections arranged next to it on the right are formed by a glass scrim. The glass fabrics expediently have different fiber orientations. The additional element 40 is via at least one fastener 50 , preferably several, on the cover element 30th , or especially on the forehead area 32 attached. In particular, the corresponding material section is 42 of the additional element 40 attached there as the additional element 40 becomes an additional element only after a first material or, in particular, a potting compound has been introduced into the arrangement space. The first material or a potting compound is not explicitly shown here. It can be seen that the additional element 40 the arrangement space along the rotor axis R. or also completely or essentially completely radially. For the arrangement of the material sections 42 or the additional element 40 this expediently has an opening, the geometry of which is attached to an outer circumferential surface of the rotor shaft 12th is adapted.

2 essentially shows those from the 1 known arrangement, so that the essential features are no longer repeated in the present case. A crucial difference is that the cover element 30th , together with the material section arranged thereon 42 , not yet on the laminated core 14th or the faceplate 16 is arranged. It is also shown that the material section 42 presently only comprises one material layer or one layer. This is, for example, a fleece. Such a rotor is expediently provided for lower power or speed classes. Special attention is paid to the fact that the filling volumes are the same, ie that the only material section 42 in 2 has the same or substantially the same thickness as the three material sections, which in the 1 are sketched. This is particularly advantageous in terms of assembly and manufacturing effort.

3 shows along a rotor axis R. seen a rotor 10 , partly still a front disk 16 is recognizable. There is a section of material on this 42 arranged, in the present case in particular an outer, non-round or non-round, in particular hexagonal, circumferential surface 46 it can be seen what a twisting of the material section 42 around the rotor axis R. can prevent. The actual configuration is not limited to such a hexagonal configuration. The material section is expedient 42 or the material sections are designed in such a way that an adaptation to the rest of the shape of the rotor is made possible. A circular opening can also be seen 44 of the material section 42 for arrangement on a rotor shaft 12th .

List of reference symbols

10

rotor

12th

Rotor shaft

14th

Laminated core

16

End disk

20th

Winding head

30th

Cover element

32

Forehead area

34

Perimeter area / envelope area

40

Additional element

42

Material section

44

opening

46

Circumferential surface

50

Fastener

A.

Arrangement space

R.

Rotor axis

QUOTES INCLUDED IN THE DESCRIPTION

This list of the documents listed by the applicant was generated automatically and is included solely for the better information of the reader. The list is not part of the German patent or utility model application. The DPMA assumes no liability for any errors or omissions.

Patent literature cited

• DE 102016205813 A1 [0002]

Claims (13)

Rotor (10) for an energized synchronous machine, comprising a laminated core (20) with a winding, the laminated core (20) extending along a rotor axis (R), wherein a cover element (30) is arranged at least at a first end of the laminated core (20) which forms or forms an arrangement space (A) towards the laminated core (20), wherein the arrangement space (A) is at least partially filled with a first material, in particular a potting material, and wherein in the arrangement space (A) at least one material section (42) is arranged which, in cooperation with the first material, forms an additional element (40) forms a composite material. Rotor after Claim 1 wherein a plurality of material sections (42) are arranged along the rotor axis (R) for forming the additional element (40). Rotor after Claim 1 or 2 , wherein the at least one material section (42) is a fleece, woven fabric and / or scrim. Rotor according to one of the preceding claims, wherein the additional element (40) has a plurality of different formed material sections (42). Rotor according to one of the preceding claims, wherein the at least one material section (42) has an opening (18) which is designed for arrangement on the rotor shaft (12). Rotor according to one of the preceding claims, wherein the at least one material section (42) has a radially oriented circumferential surface (46) which is angular or non-circular. Rotor according to one of the preceding claims, wherein the at least one material section (42) is fixed or pre-fixed on the cover element (30) by at least one fastening element (50). Rotor according to one of the preceding claims, the contacting of the winding being formed in the region of the first end of the laminated core (14). Engine series, comprising a plurality of electrical machines which have rotors (10) according to one of the preceding claims, wherein the plurality of electrical machines differ with regard to at least one parameter, in particular the speed class, and wherein the additional elements (40) arranged in the rotors (10) have the same or essentially the same thickness, wherein a layer structure of the additional elements (40) is different. Electrical machine, comprising at least one rotor (10) according to one of the Claims 1 - 8th . A method for manufacturing a rotor for an energized synchronous machine, comprising the steps: - Providing a laminated core (20) with a winding; - Provision of a cover element (30) for arrangement at a first end of the laminated core (20), an arrangement space (A) being formed between the first end of the laminated core (20) and the cover element (30); - Arranging at least one material section (42) on the rotor (10) or on the cover element (30); - Arranging the cover element (30) at the first end of the rotor (10); - Potting or casting around the laminated core (20) with a first material, in particular a potting compound, so that an additional element (40) is formed from a composite material in cooperation with the at least one material section (42). Procedure according to Claim 11 comprising the steps of: - attaching the at least one material section (42) to the cover element (30); - Arranging the cover element (30) on the rotor (10). Method according to one of the Claims 11 until 12th , comprising the step: encapsulating, overmolding or encapsulating over the cover element (30), which for this purpose has at least one opening for introducing the first material.

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