阅读说明：本技术 转子和电机 (Rotor and motor ) 是由 J.布格豪斯 D.P.莫里斯科 于 2018-04-27 设计创作，主要内容包括：本发明涉及用于一种用于电机的转子。这种转子具有由至少一种金属玻璃构成的圆柱形的基体(4)。所述基体(4)的侧面具有至少一个凹部(82)。此外,本发明涉及一种电机。这种电机具有所述转子和定子。所述定子具有至少一种金属玻璃。(The invention relates to a rotor for an electric machine. The rotor has a cylindrical base body (4) made of at least one metallic glass. The side of the base body (4) has at least one recess (82). The invention further relates to an electric machine. The motor has the rotor and the stator. The stator has at least one metallic glass.)

1. Rotor (2) for an electric machine (1), having a cylindrical base body (4) made of at least one metallic glass, wherein a lateral surface (5) of the base body (4) has at least one recess (81, 82, 83, 84, 85).

2. A rotor (2) according to claim 1, characterized in that the rotor's basic body (4) has at least one ferritic metallic glass with a maximum magnetic permeability of at least 1000.

3. A rotor (2) according to claim 1 or 2, characterized in that the rotor has at least one chamber (6) in its base body (4), wherein at least one permanent magnet (71, 72) is arranged in each chamber (6).

4. A rotor (2) according to claim 3, characterized in that the shortest distance (a) between the side face (5) and the chamber (6) is in the range of 1mm to 10 mm.

5. The rotor (2) according to any one of claims 1 to 4, characterized in that the rotor has a plurality of recesses (81) configured as grooves having a depth in the range of 1/70 of the diameter of the rotor (2) to 1/35 of the diameter of the rotor (2).

6. A rotor (2) according to claim 3 or 4, characterized in that the rotor has a plurality of recesses (82, 83) leading from the side (5) all the way to the chamber (6).

7. A rotor (2) according to any of claims 1-6, characterized in that at least one recess (81, 83) extends over at least 80% of the length of the rotor (2).

8. A rotor (2) according to any of claims 1-4, characterized in that the rotor has recesses (84, 85) extending as female embossments with a non-constant profile over the entire side face (5) in the axial direction of the rotor (2).

9. Electric machine (1) with a rotor (2) according to one of claims 1 to 8 and with a stator (3) with at least one metallic glass.

10. The machine according to claim 9, characterized in that the stator (3) has at least one metallic glass, which is also contained in the base body (4) of the rotor (2).

Technical Field

The present invention relates to a rotor for an electric machine. The invention further relates to an electric machine comprising a rotor.

Background

A member composed of a magnetic material is used as a rotor or a stator in an electric motor. They must have good soft magnetic properties, in particular high saturation polarization, high permeability and low core loss.

Eddy currents occur in the rotor during operation of the electric machine. This can cause the rotor to heat up.

Disclosure of Invention

A rotor for an electric machine has a cylindrical base body. The substrate is made of at least one metallic glass (BMG). The side of the base body has at least one recess. Such rotors can be manufactured in a net-shape (net-shape) process, such as an injection molding process, since metallic glass can be manufactured by: the amorphous starting powder (Ausgangspulver) and/or the Granulate (Granulate) are consolidated (konsolidiert) according to the processing steps by induction heating. For this reason, a temperature higher than the glass temperature and lower than the crystallization temperature is required. These temperatures are in particular in the range from 400 ℃ to 600 ℃. Furthermore, it is possible to use a generated or added method in which an amorphous powder is consolidated at a temperature above the crystallization temperature. Metallic glasses typically have less than 0.2% shrinkage during thermal consolidation due to the lack of phase transformation. The rotor is accordingly produced close to the final contour. The at least one recess can be produced already in the manufacturing step without subsequent machining.

Metallic glasses can be produced not only in a magnetic manner but also in a non-magnetic manner depending on their composition. Thus, a non-magnetic separation in the rotor can be achieved. However, in order to be able to achieve optimum use in the electric machine, the rotor preferably has at least one ferritic metallic glass in its base body, which has a maximum magnetic permeability of at least 1000. Furthermore, the metallic glass has a saturation polarization of preferably at least 1T. For this reason, a ferritic iron-based alloy can be particularly used as a raw material for the ferritic metallic glass. This magnetic permeability is significantly higher than that of the electrical plates typically used in such rotors.

The base body can be connected to the other components of the rotor, for example, by means of laser welding or gluing.

Furthermore, it is preferred that the rotor has at least one chamber in its base body. At least one permanent magnet is arranged in each chamber. However, it is also possible to arrange a plurality of permanent magnets, in particular two permanent magnets each, in each chamber. These permanent magnets, which are composed of hard magnetic material, enhance the interaction of the rotor and the stator of the electrical machine. The cavity can be created when the base body is produced from metallic glass and the permanent magnet can then be inserted into the cavity. It is particularly preferred that the shortest distance between the side and the chamber is in the range from 1mm to 10mm, particularly preferably in the range from 2mm to 10 mm. An optimal magnetic interaction with the stator can thereby be achieved.

In one embodiment, the rotor has a plurality of recesses in the form of grooves in the side of its base body. The depth of these grooves is in the range of 1/70 a diameter of the rotor to 1/35 a diameter of the rotor. The diameter of the rotor is at least 5mm here, in particular for very small electric machines. The diameter of the rotor may be up to several hundred millimetres depending on the application. It is furthermore preferred that the depth is in the range of 0.2mm to 5.0 mm. These grooves significantly reduce the eddy currents on the rotor surface. Furthermore, they act as air blades and thus support the cooling of the electric machine.

In a further embodiment, the rotor has recesses which open out into the chamber from the side, preferably in the region of the base body made of soft-magnetic metallic glass, which weaken the base body in a targeted manner at locations with high magnetic losses in the magnet by removal of the soft-magnetic material, thereby achieving a local flux density weakening (flussdichchtesch ä chung) and thus a reduction of the induced eddy currents.

In all the embodiments of the rotor described so far, it is preferred that the at least one recess extends over at least 80% of the length of the rotor, particularly preferably over at least 90% of the length, particularly preferably over the entire length. If the recess is designed as a groove, the turbulence and the air-vane action are thereby minimized. The recess, which leads from the side face into the chamber, which functions as a negative contour in the pole contour, is located not only at various points on the side face but also extends over a large part of the rotor length. In this way the surface field (Oberfelder) inside the rotor field is reduced. Since these surface fields are mainly responsible for the initiation of eddy currents in the magnetic material, magnetic losses can be reduced by these measures. In addition, these measures can have a positive effect on the torque ripple.

In a further embodiment, the rotor has a recess which extends as a female embossing with a non-constant profile over the entire side face in the axial direction of the rotor. For this purpose, the linear shape, such as, for example, a contour that is constantly parallel to the axis of rotation, is modified in particular according to a square or linear trend of the spline shape. In this way, eddy current losses in the magnetic material caused by surface fields can also be reduced.

The use of at least one metallic glass in the substrate also enables the integration of security features into the surface. This can be done, for example, by storing the QR code as a negative image in an extruder with which the substrate is made from its raw powder.

The motor has the rotor and has a stator. The stator has at least one metallic glass. The stator preferably has at least one metallic glass, which is also contained in the base body of the rotor. In this way, the magnetic flux in the stator is matched to the magnetic flux in the rotor.

Drawings

Embodiments of the invention are illustrated in the drawings and are explained in detail in the following description.

Fig. 1 shows a schematic cross-sectional view of an electrical machine according to an embodiment of the invention.

Fig. 2a shows an isometric illustration of a rotor according to an embodiment of the invention.

Fig. 2b shows an isometric illustration of a rotor according to another embodiment of the invention.

Fig. 2c shows an isometric illustration of a rotor, again according to another embodiment of the invention.

Figure 3a shows an isometric illustration of a cut-away cutaway portion of a rotor according to an embodiment of the present invention.

Figure 3b shows an isometric illustration of a cut-away cutaway portion of a rotor according to another embodiment of the present invention.

Figure 4a shows an isometric illustration of a cut-away cutaway portion of a rotor, again according to another embodiment of the present invention.

Figure 4b shows an isometric illustration of a cut-away cutaway portion of a rotor, again according to another embodiment of the present invention.

Detailed Description

Fig. 1 shows a section through an electric machine 1 which is designed as a permanently excited synchronous machine, having a cylindrical rotor 2 and a stator 3, in the base body 4 of the rotor 2, below its side 5, there is a chamber 6 which has a shortest distance a of 5mm from the side 5, two permanent magnets 71, 72 are arranged in the chamber 6, the stator 3 and the base body 4 are each composed of soft magnetic metallic glass based on a ferritic iron-based alloy having a saturation polarization greater than 1.6T and a maximum magnetic permeability greater than 10,000 (maxiperfect permability ä T), the stator 3 and the base body 4 can each be produced in a production method or by an injection molding method by adding raw powder to a mold (matrix) by means of injection molding and subsequently pressurizing and heat treating them.

Fig. 2a to 2c show three exemplary embodiments of a rotor 2 which has recesses 81 in the form of grooves in its side faces. The rotors 2 each have a diameter of 100mm, and the recesses 81 each have a depth of 1.5 mm. All recesses extend over the entire length of the rotor. In this case, in the first exemplary embodiment according to fig. 2a, the recess runs parallel to the longitudinal axis of the rotor 2. In a second embodiment according to fig. 2b, the recess extends in a continuously chamfered manner. In a third embodiment according to fig. 2c, the recess extends in a V-shape.

In the fourth exemplary embodiment shown in fig. 3a, circular recesses 82 are provided in the side 5 at the locations with high magnetic losses, which recesses open all the way into the chamber 6. In a fifth embodiment, shown in fig. 3b, the recess 83 in the side 5 has the shape of a female profile that leads into the chamber 6, which extends in an irregular shape over more than 80% of the length of the rotor 2.

Fig. 4a and 4b show further exemplary embodiments of the rotor 2, in which the flanks 5 each have a recess which extends as a female embossing (Negativpr ä gun) with a non-constant contour over the entire flank 5 in the axial direction of the rotor 2, in the sixth exemplary embodiment according to fig. 4a the recess 84 has the shape of a spline (Splines) without nodes, and in the seventh exemplary embodiment according to fig. 4b the recess 85 has the shape of a spline with a plurality of nodes.