Rotor for an electric motor for a motor vehicle

Abstract

The invention relates to a rotor for an electric motor for a motor vehicle, comprising a rotor base body, wherein the rotor base body extends circularly around an axis of rotation, wherein the rotor base body comprises an inner rotor surface extending radially to the axis of rotation and a support edge connected to the inner rotor surface extending axially to the axis of rotation, wherein permanent magnets are arranged on the inner rotor surface, which extend radially around the axis of rotation, and permanent magnets are arranged on the support edge, which extend radially around the axis of rotation, thereby forming a first rotor half.

Description

[0001] The present invention relates to a rotor for an electric motor for a motor vehicle.

[0002] In today's modern electric vehicles, efficient electric motors play a crucial role in supporting the transition to sustainable energy sources. Increasing the share of electrified drive concepts in the energy transition is a key aspect of evolving mobility. To maximize the performance of these drives, optimal magnetic coupling between the rotor and stator is essential, as it directly influences the transmissible torque of the electric motor. This application presents an innovative method that improves the magnetic coupling between the rotor and stator, thereby increasing the performance of electric motors.

[0003] The present invention relates to an innovative rotor arrangement which solves the problems of the prior art.

[0004] According to the invention, a rotor for an electric motor for a motor vehicle according to claim 1 is provided.

[0005] Advantageous embodiments can be found in the dependent claims and the description.

[0006] The invention relates to a rotor for an electric motor for a motor vehicle, comprising a rotor base body, wherein the rotor base body extends circularly around an axis of rotation, wherein the rotor base body comprises an inner rotor surface extending radially to the axis of rotation and a support edge connected to the inner rotor surface extending axially to the axis of rotation, wherein permanent magnets are arranged on the inner rotor surface, which extend radially around the axis of rotation on the inner rotor surface, and permanent magnets are arranged on the support edge, which extend radially around the axis of rotation, thereby forming a first rotor half.

[0007] The radial arrangement of the magnets does not mean that the radius of the permanent magnets relative to the axis of rotation becomes larger. The permanent magnets are perpendicular to the axis of rotation, or lie on the axis of rotation, or on an axis parallel to the axis of rotation, and run along a circular path radially further outward from the axis of rotation.

[0008] In an advantageous further development, the permanent magnets on the inner surface of the rotor are perpendicular to the permanent magnets on the support edge.

[0009] This arrangement allows the advantages of a radial flux machine and an axial flux machine to be combined.

[0010] A radial flux machine and an axial flux machine are both types of three-phase machines, i.e., electric motors, but they have different structures and operating principles.

[0011] In a radial flux machine, the magnetic flux is perpendicular to the axis of rotation. The magnetic flux flows radially to a stator wall, specifically the rotor body, and into the rotor. The rotor's permanent magnets are arranged at an angle of approximately 90 degrees to the stator wall, specifically to the first and second rotor bodies, i.e., at the supporting edge of each rotor body. The magnetic flux thus flows parallel to the stator wall and acts on the permanent magnets, or the rotor, to generate a torque. The permanent magnets at the supporting edge are therefore axial flux permanent magnets.

[0012] The first rotor body refers to the first rotor half and the second rotor body refers to the second rotor half.

[0013] In an axial flux machine, the magnetic flux runs parallel to the axis of rotation. The magnetic flux flows axially from the stator wall, specifically from the first and second rotor bodies, into the rotor. The permanent magnets are arranged at an angle of approximately 0 degrees to the stator wall, meaning they run parallel to the stator, and thus the magnetic flux flows perpendicular to the stator wall. The magnetic flux acts directly on the permanent magnets to generate torque. Therefore, the permanent magnets on the inner surface of the rotor are radial flux permanent magnets.

[0014] The rotor according to the invention combines both design variants, in particular the simultaneous use of radial flux permanent magnets and axial flux permanent magnets in one rotor.

[0015] The main difference between radial and axial flux machines lies in their structure and the way in which the magnetic flux acts on the permanent magnets or the rotor. Radial flux machines are generally larger and heavier than axial flux machines, but are also more efficient at high speeds. Conversely, axial flux machines are smaller and lighter, but are also more efficient at low speeds. The arrangement according to the invention allows these advantages to be combined.

[0016] In a particularly advantageous embodiment, the inner surface of the rotor and the support edge are at a 90-degree angle to each other. In a further advantageous embodiment, the inner surface of the rotor and the support edge are at an angle between 85 and 95 degrees to each other. These angles refer to the contact surfaces for the permanent magnets.

[0017] The axis of rotation of an electric motor is the imaginary line along which the electric motor can rotate. It is defined as the axis around which the electric motor rotates during its rotational movement.

[0018] The axis of rotation of the electric motor is the axis around which the main components of the motor, such as the rotor, rotate.

[0019] In an advantageous further development, the permanent magnets are arranged on an inner surface of the support edge. The inner surface is the surface that extends around the axis of rotation and points in the direction of the axis of rotation.

[0020] The axis of rotation passes through a free inner diameter of the rotor. During operation, the rotor rotates around this axis.

[0021] The free inner diameter is the diameter of the rotor's interior. It is therefore the diameter of the rotor's cavity that, in its uninstalled state, is not occupied by any components of the electric motor.

[0022] In a further development, the rotor comprises a second rotor half, which is designed according to the first rotor half, wherein the first rotor half and the second rotor half are arranged to each other in such a way that the permanent magnets of the respective inner rotor surfaces of the first rotor half and the second rotor half are opposite each other.

[0023] In a further development, the first rotor half and the second rotor half are connected to each other by a rotor bandage, the rotor bandage extending around the rotor on a radially circumferential outer surface of the rotor.

[0024] The rotor bandage can overlap the first rotor half and the second rotor half simultaneously on their circumferential outer surface.

[0025] In a further training, the rotor bandage is designed as a fiberglass or carbon fiber bandage, or includes one, with the rotor bandage comprising an epoxy resin matrix. These bandages can also be referred to as fillers.

[0026] An epoxy resin matrix is ​​a plastic made from epoxy resins. Epoxy resins are a type of polymer that are polymerized through a chemical reaction between an epoxy resin and a catalyst.

[0027] An epoxy resin matrix is ​​a solid, elastic material that can be made from a mixture of epoxy resin, fillers, and possibly other additives. The epoxy resin matrix can be used as a substrate material for manufacturing the rotor bandage.

[0028] The epoxy resin matrix is ​​characterized by its good mechanical strength, resistance to chemicals, and temperature stability. It can also be modified with various fillers and additives to tailor its properties.

[0029] In a further training, the permanent magnets arranged on the inner surface of the rotor comprise an outer radius and an inner radius.

[0030] In a further training, the outer radius of the permanent magnets on the inner surface of the rotor corresponds to an outer radius of the inner surface of the rotor, and the inner radius of the permanent magnets on the inner surface of the rotor corresponds to a radius of a free inner diameter of the inner surface of the rotor.

[0031] The outer radius is the radius of the permanent magnet or the inner surface of the rotor that is located radially outwards from the rotor's axis of rotation. The inner radius is the radius of the permanent magnet or the inner surface of the rotor that is located radially inwards from the rotor's axis of rotation.

[0032] In a further training course, the permanent magnets are attached to the inner surface of the first rotor half by a magnetic bandage and / or the permanent magnets are attached to the inner surface of the second rotor half by a magnetic bandage.

[0033] In a further training, the permanent magnets at the support edge are materially bonded to the support edge of the first rotor half and / or the second rotor half.

[0034] A material-bonded connection is a bond between two metallic surfaces created by a third substance, such as a plastic or an epoxy resin. This connection is "material-bonded" because it is not created by mechanical forces or mechanical fasteners, such as screws or adhesives, but by the chemical bond between the two surfaces and the third substance.

[0035] In a further training course, the permanent magnets are attached to the support edge by gluing them to the support edge of the first rotor half and / or the second rotor half.

[0036] In a further training, the rotor body of the first rotor half and / or the second rotor half is made of or comprises a sintered material.

[0037] The invention is described below by way of example only, with reference to the drawings. The drawings show: Fig. Figure 1 shows a first rotor half of the rotor for an electric motor according to an embodiment of the invention; and Fig. Figure 2 shows a rotor for an electric motor according to an embodiment of the invention.

[0038] Fig. Figure 1 shows a rotor 100 for an electric motor for a motor vehicle, comprising a rotor base body 110, wherein the rotor base body 110 extends circularly around an axis of rotation 200, wherein the rotor base body 110 comprises an inner rotor surface 111 extending radially to the axis of rotation 200 and a support edge 114 connected to the inner rotor surface 111 and extending axially to the axis of rotation 200, wherein permanent magnets 120 are arranged on the inner rotor surface 111, which extend radially around the axis of rotation 200 on the inner rotor surface 111, and permanent magnets 120 are arranged on the support edge, which extend radially around the axis of rotation 200, thereby forming a first rotor half 130.

[0039] The permanent magnets 120 arranged on the inner surface 111 of the rotor comprise an outer radius 112 and an inner radius 113.

[0040] The outer radius 112 of the permanent magnets 120 on the rotor inner surface 111 corresponds to an outer radius of the rotor inner surface 111 and the inner radius 113 of the permanent magnets 120 on the rotor inner surface 111 corresponds to a radius of a free inner diameter of the rotor inner surface 111.

[0041] In a radial flux machine, the magnetic flux is perpendicular to the axis of rotation 200. The magnetic flux extends radially towards a stator wall, in particular the rotor body 110, and into the rotor. The permanent magnets 120 of the rotor 100 are arranged at an angle of approximately 90 degrees to the stator wall, in particular to the first and second rotor bodies 110, i.e., at the support edge 114 of the respective rotor body 110. The magnetic flux thus flows parallel to the stator wall and acts on the permanent magnets 120 and the rotor 100 to generate a torque. The permanent magnets 120 at the support edge 114 are therefore axial flux permanent magnets 122.

[0042] In an axial flux machine, the magnetic flux runs parallel to the axis of rotation 200. The magnetic flux flows axially from the stator wall, in particular from the first rotor body 110 and the second rotor body 110, into the rotor 100. The permanent magnets 120 are arranged at an angle of approximately 0 degrees to the stator wall, in particular from the first rotor body 110 and the second rotor body 110, and thus run parallel to a stator (not shown), which means that the magnetic flux flows perpendicular to the stator wall. The magnetic flux acts directly on the permanent magnets 120 to generate the torque. The permanent magnets 120 on the inner surface of the rotor 111 are therefore radial flux permanent magnets 121.

[0043] The rotor 100 according to the invention combines both design variants.

[0044] The Fig.Figure 2 shows a rotor 100 for an electric motor for a motor vehicle, comprising a rotor base body 110, wherein the rotor base body 110 extends circularly around an axis of rotation 200, wherein the rotor base body 110 comprises an inner rotor surface 111 extending radially to the axis of rotation 200 and a support edge 114 connected to the inner rotor surface 111 and extending axially to the axis of rotation 200, wherein permanent magnets 120 are arranged on the inner rotor surface 111, which extend radially around the axis of rotation 200 on the inner rotor surface 111, and permanent magnets 120 are arranged on the support edge, which extend radially around the axis of rotation 200, thereby forming a first rotor half 130.

[0045] The rotor 100 comprises a second rotor half 140, which is designed in accordance with the first rotor half 130, wherein the first rotor half 130 and the second rotor half 140 are arranged to each other such that the permanent magnets 120 of the respective inner rotor surfaces of the first rotor half 130 and the second rotor half 140 are opposite each other.

[0046] The first rotor half 130 and the second rotor half 140 are connected to each other by a rotor bandage 150, the rotor bandage 150 extending around the rotor 100 on a radially circumferential outer surface of the rotor 100.

[0047] The permanent magnets 120 arranged on the inner surface 111 of the rotor comprise an outer radius 112 and an inner radius 113.

[0048] The outer radius 112 of the permanent magnets 120 on the rotor inner surface 111 corresponds to an outer radius of the rotor inner surface 111 and the inner radius 113 of the permanent magnets 120 on the rotor inner surface 111 corresponds to a radius of a free inner diameter of the rotor inner surface 111.

[0049] The invention is not limited to the described embodiments. Within the scope of the invention, all described and / or drawn features can be combined with one another as desired, unless otherwise stated. Reference sign 100 Rotor 110 rotor base bodies 111 Rotor inner area 112 outer radius 113 inner radius 114 Support edge 120 permanent magnets 121 radial flux permanent magnet 122 Axial flux permanent magnet 130 First rotor half 140 Second rotor half 150 Rotor bandage 200 Rotation axis

Claims

Rotor (100) for an electric motor for a motor vehicle, comprising a rotor body (110), wherein the rotor body (110) extends circularly around an axis of rotation (200), wherein the rotor body (110) comprises an inner rotor surface (111) extending radially to the axis of rotation (200) and a support edge (114) connected to the inner rotor surface (111) extending axially to the axis of rotation (200), wherein permanent magnets (120) are arranged on the inner rotor surface (111) extending radially around the axis of rotation (200) on the inner rotor surface (111) and permanent magnets (120) are arranged on the support edge extending radially around the axis of rotation (200), thereby forming a first rotor half (130). Rotor (100) for an electric motor for a motor vehicle according to claim 1, characterized in that the rotor (100) comprises a second rotor half (140) which is designed according to the first rotor half (130), wherein the first rotor half (130) and the second rotor half (140) are arranged to each other such that the permanent magnets (120) of the respective inner rotor surfaces of the first rotor half (130) and the second rotor half (140) are opposite each other. Rotor (100) for an electric motor for a motor vehicle according to claim 2, characterized in that the first rotor half (130) and the second rotor half (140) are connected to each other by a rotor bandage (150), wherein the rotor bandage (150) extends around the rotor (100) on a radially circumferential outer surface of the rotor (100). Rotor (100) for an electric motor for a motor vehicle according to claim 3, characterized in that the rotor bandage (150) is designed as a fiberglass bandage or carbon fiber bandage, wherein the rotor bandage (150) comprises an epoxy resin matrix. Rotor (100) for an electric motor for a motor vehicle according to one of the preceding claims, characterized in that the permanent magnets (120) arranged on the inner surface (111) of the rotor comprise an outer radius (112) and an inner radius (113). Rotor (100) for an electric motor for a motor vehicle according to claim 5, characterized in that the outer radius (112) of the permanent magnets (120) on the rotor inner surface (111) corresponds to an outer radius of the rotor inner surface (111) and the inner radius (113) of the permanent magnets (120) on the rotor inner surface (111) corresponds to a radius of a free inner diameter of the rotor inner surface (111). Rotor (100) for an electric motor for a motor vehicle according to one of the preceding claims, characterized in that the permanent magnets (120) are attached to the inner surface (111) of the first rotor half (130) by a magnetic bandage and / or the permanent magnets (120) are attached to the inner surface (111) of the second rotor half (140) by a magnetic bandage. Rotor (100) for an electric motor for a motor vehicle according to one of the preceding claims 2 to 7, characterized in that the permanent magnets (120) are materially bonded to the support edge (114) of the first rotor half (130) and / or the second rotor half (140). Rotor (100) for an electric motor for a motor vehicle according to one of the preceding claims 2 to 8, characterized in that the permanent magnets (120) are attached to the support edge (114) by gluing to the support edge (114) of the first rotor half (130) and / or the second rotor half (140). Rotor (100) for an electric motor for a motor vehicle according to one of the preceding claims 2 to 9, characterized in that the rotor base body (110) of the first rotor half (130) and / or the second rotor half (140) are made of or comprise a sintered material.

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