ROTOR FOR AN ELECTRIC MACHINE

Description

State of the art

[0001] The invention relates to a rotor for an electrical machine according to the preamble of the main claim.

[0002] A rotor for an electrical machine is already known from US2020266677 A1, comprising a rotor body rotatable about a rotor axis and comprising a plurality of rotor poles, each with a pole center, wherein the rotor body has a rotor base body which has a plurality of recesses on its outer circumference distributed over the outer circumference, into which two magnets and a separate pole segment are inserted to form one of the rotor poles. Between the respective pole segment and the respective recess of the rotor base body, a V-shaped, U-shaped or arc-shaped magnet pocket is formed, each having two pocket openings towards the outer circumference of the rotor body and serving to accommodate the two magnets. The rotor body is enclosed by a rotor sleeve. Advantages of the invention

[0003] The rotor according to the invention for an electrical machine with the characterizing features of the main claim has the advantage that the fastening of the magnets in the magnet pockets is improved in that the rotor sleeve is a cured fiber composite bandage, the matrix material of which has penetrated into at least one, in particular all, of the magnet pockets of the rotor body via the respective pocket openings during the production of the fiber composite bandage for the adhesive or material-lock fastening of the respective magnet of the respective magnet pocket to the rotor base body and / or to the respective pole segment.

[0004] During the production of the fiber composite bandage, for example, a wet winding process, the still-liquid matrix material, e.g., an excess amount, flows or drips, driven by gravity, into the respective magnet pocket and / or is drawn, for example, by capillary action, into the gaps formed between the respective magnet and the respective separate pole segment or between the respective magnet and the rotor base body. The penetration of the matrix material into the gaps can improve the thermal connection of the magnets to the rotor base body and / or to the pole segments, thus improving the cooling of the magnets. Furthermore, the matrix material can improve the insulation of the magnets from the rotor body.

[0005] The measures listed in the subclaims enable advantageous further developments and improvements of the rotor of the electric machine specified in the main claim.

[0006] It is particularly advantageous if a gap is provided in one or more, in particular in all, of the magnet pockets on an upper side of the respective magnet facing the respective pole segment and / or on an underside of the respective magnet opposite the upper side, which gap is at least partially filled with the matrix material. In this way, the matrix material of the fiber composite bandage is also used for fastening and cooling the magnets.

[0007] It is also advantageous if a gap is provided in the respective magnet pocket between the fiber composite bandage and a narrow side of the respective magnet facing the fiber composite bandage. This prevents eddy currents at the air gap and thus reduces electromagnetic losses.

[0008] It is very advantageous if the at least one magnet of the respective magnetic pocket is pre-fixed to a joining surface of the rotor base body and / or to a joining surface of the respective pole segment by means of an adhesive connection, in particular an adhesive coating or an adhesive film. In this way, the pole segments can be pre-fixed to the rotor base body so that the so-called wet winding of the fiber composite bandage can then take place. This ensures that the pole segments and the rotor base body form a unit during wet winding. In addition, the adhesive connection means that less matrix material is needed to fill the gaps, so that wet winding can be carried out with less matrix material. In addition, the magnets can be completely insulated from the sheet metal laminations of the rotor base body or the rotor segment by the adhesive coating or adhesive film of the adhesive connection.of the respective pole segment, so that fewer electromagnetic losses occur.

[0009] It is also advantageous if the adhesive bond has a structure, in particular a surface and / or hollow structure, for guiding the matrix material of the fiber composite bandage along a surface of the respective magnet toward the respective pole center. This ensures that the matrix material can at least partially fill the gaps despite the pre-fixing adhesive bond. For example, the magnets are encased in the matrix material, which can, for example, improve the insulation of the magnets from the rotor body.

[0010] According to an advantageous embodiment, the fiber composite bandage is magnetically non-conductive and comprises fibers, in particular carbon fibers or glass fibers, embedded in the matrix material. This creates a functional separation in the rotor, with the rotor body conducting the magnetic flux and the fiber composite bandage meeting the mechanical requirements regarding speed stability. The fiber composite bandage eliminates the need for stray webs or bridges. Furthermore, air gaps, which are required in the prior art due to joining tolerances when joining the magnets, can be eliminated.

[0011] It is advantageous if the respective recess of the rotor base body and the respective pole segment are formed in the shape of a circular sector, since in this way the V-shaped, U-shaped or arc-shaped magnetic pockets are formed as a layered intermediate space between the rotor base body and the respective pole segment.

[0012] It is also advantageous if the legs of the magnetic pocket are each arranged at an angle to the pole center, in particular symmetrically to the pole center and, in particular, diverging toward the outer circumference. This achieves a magnet arrangement that is advantageous in terms of performance and efficiency.

[0013] According to a further advantageous embodiment, the rotor base body is a laminated core and / or the respective pole segment is a laminated core or a soft magnetic composite (SMC) body. With a pole segment made of soft magnetic composite (SMC), eddy current losses in every spatial direction can be avoided.

[0014] The invention may further relate to an electrical machine having a rotor according to the invention. drawing

[0015] An embodiment of the invention is shown in simplified form in the drawing and explained in more detail in the following description. Fig.1 shows a rotor of an electrical machine according to the invention and Fig.2 a detailed view of the rotor according to Fig.1 . Description of the embodiment

[0016] Fig.1 shows a rotor according to the invention for an electrical machine. The rotor 1 of the electrical machine has a rotor body 3 rotatable about a rotor axis 2, which comprises a plurality of rotor poles 4, each with a pole center 5.

[0017] The rotor body 3 has a rotor base body 8, which has a plurality of recesses 9 distributed along its outer circumference, into which at least one magnet 10, for example two magnets 10 and a separate pole segment 11, is inserted to form one of the rotor poles 4. The magnet 10 is, for example, a permanent magnet.

[0018] The rotor base body 8, for example, is a laminated core. The respective pole segment 11 can also be a laminated core or, alternatively, a soft magnetic composite (SMC) body.

[0019] Between the respective pole segment 11 and the respective recess 9 of the rotor base body 3, a V-shaped, U-shaped, or arcuate magnetic pocket 12 is formed, each having two pocket openings 15 toward the outer circumference of the rotor body 3 and serving to accommodate at least one magnet 10. The respective recess 9 of the rotor base body 8 and the respective pole segment 11 are designed, for example, in the shape of a circular sector.

[0020] The legs of the V-shaped, U-shaped or arcuate magnetic pocket 12 are each arranged at an angle α to the pole center 5, for example symmetrical to the pole center 5 and for example diverging towards the outer circumference.

[0021] The rotor body 3 is enclosed by a rotor sleeve 16, in particular to increase the speed stability of the rotor 1. The pocket openings 15 are concealed or covered by the rotor sleeve 16.

[0022] Fig.2 shows a detailed view of the rotor after Fig.1 .

[0023] According to the invention, the rotor sleeve 16 is a cured fiber composite bandage, the matrix material 16.1 of which has penetrated into at least one, in particular all, of the magnetic pockets 12 of the rotor body 3 via the respective pocket openings 15 during the manufacture of the fiber composite bandage 16 in order to fasten the respective magnet 10 of the respective magnetic pocket 12 to the rotor base body 8 and / or to the respective pole segment 11.

[0024] During the production of the fiber composite bandage 16, the still liquid, e.g., excess, matrix material flows or drips into the respective magnetic pockets 12, for example, driven by gravity and / or by capillary action. During wet winding of the fiber composite bandage, a fiber wetted with the matrix material 16.1 is wound onto the rotor body 3, forming a fiber winding with, for example, multiple winding layers. The upper winding layers of the forming fiber composite contribute to pressing the matrix material 16.1 toward the magnetic pockets 12 by exerting appropriate pressure on the underlying winding layers.

[0025] The curing of the matrix material 16.1 can be carried out during the production of the fiber composite bandage 16, for example, by means of UV radiation for pre-curing and by means of heat for complete curing.

[0026] The fiber composite bandage 16 is magnetically non-conductive and comprises fibers 16.2, for example, carbon fibers or glass fibers, embedded in the matrix material 16.1. The respective pole segment 11 is attached to the rotor base body 8 by means of the matrix material 16.1 of the fiber composite bandage 16, indirectly via the at least one magnet 10, without any stray webs.

[0027] In one or more, in particular in all, of the magnet pockets 12, a gap 17 is provided on an upper side of the respective magnet 10 facing the respective pole segment 11 and / or on an underside of the respective magnet 10 opposite the upper side, which gap is at least partially filled with the matrix material 16.1.

[0028] In the respective magnet pocket 12, a distance A is provided between the fiber composite bandage 16 and a narrow side of the respective magnet 10 facing the fiber composite bandage 16.

[0029] The at least one magnet 10 of the respective magnet pocket 12 is pre-fixed or adhered to a joining surface 8.1 of the rotor base body 8 and / or to a joining surface 11.1 of the respective pole segment 11 by means of an adhesive bond 18, for example, a double-sided adhesive coating or an adhesive film. The adhesive bond 18 can, for example, have a structure, in particular a surface and / or hollow structure, for conducting the matrix material 16.1 of the fiber composite bandage 16 along a surface of the respective magnet 10 toward the respective pole center 5.

Claims

1. Rotor (1) for an electric machine, having a rotor body (3) rotatable about a rotor axis (2) and comprising a plurality of rotor poles (4) each with a pole centre (5), wherein the rotor body (3) has a rotor main body (8) which, at its outer periphery, has a plurality of recesses (9), which are distributed over the outer periphery and into each of which at least one magnet (10), in particular permanent magnet, and a separate pole segment (11) are inserted in order to form one of the rotor poles (4), wherein a V-shaped, U-shaped or arcuate magnet pocket (12) is formed between the respective pole segment (11) and the respective recess (9) of the rotor main body (8), the magnet pockets each having two pocket openings (15) towards the outer periphery of the rotor body (3) and serving to receive the at least one magnet (10), wherein the rotor body (3) is enclosed by a rotor sleeve (16), characterized in that the rotor sleeve (16) is a cured fibre-composite bandage, the matrix material (16.1) of which, during the production of the fibre-composite bandage (16), is introduced via the respective pocket openings (15) into at least one, in particular all, of the magnet pockets (12) of the rotor body (3) in order to fasten the respective magnet (10) of the respective magnet pocket (12) to the rotor main body (8) and / or to the respective pole segment (11).

2. Rotor according to Claim 1, characterized in that a respective gap (17), which is at least partially filled with the matrix material (16.1), is provided in one or more, in particular in all, of the magnet pockets (12) on a top side of the respective magnet (10), the top side facing the respective pole segment (11), and / or on a bottom side of the respective magnet (10), the bottom side being situated opposite the top side.

3. Rotor according to any of the preceding claims, characterized in that a distance (A) is provided in the respective magnet pocket (12) between the fibre-composite bandage (16) and a narrow side of the respective magnet (10), the narrow side facing the fibre-composite bandage (16).

4. Rotor according to any of the preceding claims, characterized in that the at least one magnet (10) of the respective magnet pocket (12) is pre-fixed to a joining surface (8.1) of the rotor main body (8) and / or to a joining surface (11.1) of the respective pole segment (11) by means of an adhesive connection (18), in particular an adhesive coating or an adhesive film, in each case.

5. Rotor according to Claim 4, characterized in that the adhesive connection (18) has a structure, in particular a surface and / or hollow structure, for passage of the matrix material (16.1) of the fibre-composite bandage (16) along a surface of the respective magnet (10) to the respective pole centre (5).

6. Rotor according to any of the preceding claims, characterized in that the fibre-composite bandage (16) is magnetically impermeable and comprises fibres (16.2), in particular carbon fibres or glass fibres, embedded in the matrix material (16.1).

7. Rotor according to any of the preceding claims, characterized in that the respective recess (9) of the rotor main body (8) and the respective pole segment (11) are in the form of a sector of a circle.

8. Rotor according to any of the preceding claims, characterized in that the limbs of the magnet pocket (12) are each arranged at an angle (α) in relation to the pole centre (5), in particular symmetrically in relation to the pole centre (5) and in particular diverging towards the outer periphery.

9. Rotor according to any of the preceding claims, characterized in that the rotor main body (8) is a laminated core and / or in that the respective pole segment (11) is a laminated core or a soft-magnetic composite (SMC) body.

10. Electric machine having a rotor (1) according to any of the preceding claims.