DE102021002130A1 - Method for assembling a rotor of an electrical machine by means of twisted sheet metal layers, as well as a corresponding rotor - Google Patents

Abstract

The invention relates to a method for assembling a rotor (1) of an electrical machine, whereby several sheet metal layers (6) are joined together (S1) to form a rotor core (3) of the rotor (1), the several sheet metal layers (6) are arranged one above the other that individual sheet metal cuts (7) in the several sheet metal layers (6) form at least one magnet receiving pocket (5, 8) for a magnet (2, 9) of the rotor (1) (S2), and the magnet (2, 9) in the at least one stomach pocket (5, 8) is inserted, a gap (10) between the magnet (2, 9) and at least one side wall (11) of the at least one magnet pocket (5, 8) being created (S3), the several sheet metal layers (6) are rotated relative to each other, whereby the gap (10) is reduced in such a way that the magnet (2, 9) is fixed in the magnet receiving pocket (5, 8). The invention also relates to a rotor (1 ).

Description

The invention relates to a method for assembling a rotor of an electrical machine, with several sheet metal layers being joined together to form a rotor core of the rotor. The several sheet metal layers are arranged one above the other so that individual sheet metal cuts in the several sheet metal layers form at least one magnet receiving pocket for a magnet of the rotor and the magnet is inserted into the at least one magnet receiving pocket, a gap being created between the magnet and at least one side wall of the at least one magnet receiving pocket .

The invention also relates to a rotor for an electrical machine.

Nowadays, magnets for fastening in a rotor of an electrical machine are fastened in pockets in a rotor sheet by means of molding or extrusion coating or gluing. Fillers can be used to fix the magnets. The use of the filler has negative properties. In particular, there is poor heat transfer from the magnet into the laminated core through the filler. Furthermore, the filler can have a negative influence on the formation of the magnetic field of the magnet. Furthermore, additional components must be purchased for the individual process steps or systems for manufacturing the rotor for the joining process by means of the filler.

Another possibility in the prior art for fixing the magnets is clamping or caulking the magnets through a pre-punched tab in the laminated core or through subsequent caulking. In this way, the magnet is fixed in the pocket by applying pressure. For example, this is done in the DE 10 2016 211 711 A1 and in the DE 10 2011 078 054 A1 disclosed. When jamming or caulking, an air gap is created, which causes poor heat transfer between the magnet and the laminated core. Furthermore, the air gap can negatively affect the magnetic field. The punctual loading of the magnets by caulking can cause damage in the joining process. For example, the magnets can be worn away by the pre-cut tabs. The punctual loading of the magnet when caulking in the laminated core can cause damage to the magnet, such as breaks or scratches. This would result in high process requirements in terms of quality. Clamping or caulking also has negative effects on the long-term load capacity due to point loads on the magnet, especially in the case of vibrations and high frequencies at high speeds.

For example, the DE 10 2010 044 521 A1 , DE 10 2015 007 138 A1 and the DE 10 2014 017 305 A1 other ways to manufacture a rotor. In these documents, the magnets are achieved by means of corresponding bevels of the magnetic poles in an axial length.

For example, the DE 10 2014 019 217 A1 that the magnet pockets of the rotor are already beveled according to a continuous bevel. In this way, the sheet metal stacks are already firmly fixed when they are stacked.

The object of the present invention is thus that a manufacturing process for a rotor can be carried out more simply and without additional components.

This object is achieved by a method and a rotor according to the independent claims. Meaningful further developments result from the subclaims.

One aspect of the invention relates to a method for assembling a rotor of an electrical machine, wherein a plurality of sheet metal layers are joined together to form a rotor core of the rotor. The multiple sheet metal layers are arranged one above the other so that individual sheet metal cuts in the multiple sheet metal layers form at least one magnet receiving pocket for a magnet of the rotor, and the magnet is inserted into the at least one magnetic receiving pocket, with a gap between the magnet and at least one side wall of the at least one magnet receiving pocket arises. The multiple sheet metal layers are twisted relative to one another, as a result of which the gap is reduced in such a way that the magnet is fixed in the magnet receiving pocket.

With the proposed method, the magnet can be fixed by jamming without using additional aids such as joining material or adhesives or clamping straps or the possibilities mentioned in relation to the prior art. Thus, the fixation of the magnet can be carried out more easily and efficiently. In particular, there is a more efficient process step for manufacturing the rotor. Thus, in particular not as compared to the prior art, the fixing or the magnetic fixing does not take place by clamping straps, but by twisting, in particular alternating twisting, of the sheet metal layers. By twisting the sheet metal overhangs of the sheet metal layers to each other can fix the magnet in the magnet receiving pocket.

In particular, the proposed method can be used to produce the rotor more efficiently. In particular, the proposed method can solve the disadvantages mentioned in relation to the prior art. For example, the heat transfer from the magnet to the laminated rotor core can be improved since there is a smaller or smaller air gap or no other material (adhesive or plastic) between the magnet and the laminated rotor core. This means that the temperature in the rotor and thus in the entire system can be reduced. By reducing the gap between the magnet and the side walls of the magnet receiving pocket, an improved formation of the magnetic field can take place. As a result, the magnetic properties of the rotor increase. In particular, the temperature of the rotor and the temperature of the magnets can be reduced, as a result of which more cost-effective magnets can be used. In this way, for example, the need for rare raw materials or rare earths can be reduced. By reducing the temperature, a lower power loss and an increase in efficiency can be achieved through a smaller design of a cooling system of the rotor. In particular, by dispensing with additional materials, a weight saving of the rotor can be achieved, which is particularly efficient for the electrical machine.

Due to the simple and effective fixation of the magnet, the rotor can be used in more powerful machines and in machines with higher speeds, since the permanent and safe fixation of the magnet is achieved. By dispensing with additional fastening materials for the magnet, manufacturing costs in the manufacturing process of the rotor can be reduced. In particular, the smaller number of elements of the rotor can increase the efficiency of the electrical machine.

For example, by means of the proposed method, a magnet fixation in the rotor of a permanently excited electric motor can be achieved or carried out by interleaving the sheet metal layers in the rotor core.

Another aspect of the invention relates to a rotor for an electrical machine with a laminated rotor core, the rotor being produced by means of a method according to the previous aspect.

Further advantages, features and details of the invention emerge from the following description of preferred exemplary embodiments and on the basis of the drawings. The features and combinations of features mentioned above in the description as well as the features and combinations of features mentioned below in the description of the figures and / or shown alone in the figures can be used not only in the respectively specified combination, but also in other combinations or alone, without the scope of the Invention to leave.

• 1A eine schematische Darstellung von Bestandteilen eines Rotor;
• 1 B eine schematische Darstellung eines Rotorblechpakets des Rotors aus 1A;
• 1C eine schematische Darstellung eines Magneten in einer Magnetaufnahmetasche des Rotorblechpakets aus 1 B;
• 2A eine beispielhafte Draufsicht einer Drehvorrichtung zum Montieren des Rotors aus 1C;
• 2B eine beispielhafte Seitenansicht der Drehvorrichtung aus 2A;
• 3A eine Draufsicht eines weiteren Ausführungsbeispiels der Drehvorrichtung aus 2A;
• 3B eine Seitenansicht der Drehvorrichtung aus 3A;
• 4A eine Draufsicht eines weiteren Ausführungsbeispiels der Drehvorrichtung aus 2A mittels einer weiteren Ausführungsform des Werkzeugs der Drehvorrichtung;
• 4B eine Seitenansicht der Drehvorrichtung aus 4A;
• 4C eine Ansicht des Werkzeugs der Drehvorrichtung aus 4A; und
• 5 eine schematische Prozessabfolge einer Montage eines Rotors.

The following figures show in:

• 1A a schematic representation of components of a rotor;
• 1 B. a schematic representation of a rotor core of the rotor from 1A ;
• 1C a schematic representation of a magnet in a magnet receiving pocket of the rotor core 1 B. ;
• 2A an exemplary top view of a rotating device for mounting the rotor 1C ;
• 2 B an exemplary side view of the rotating device 2A ;
• 3A a plan view of a further embodiment of the rotating device 2A ;
• 3B a side view of the rotating device from 3A ;
• 4A a plan view of a further embodiment of the rotating device 2A by means of a further embodiment of the tool of the rotating device;
• 4B a side view of the rotating device from 4A ;
• 4C a view of the tool of the turning device 4A ; and
• 5 a schematic process sequence for assembling a rotor.

For example, the 1A a schematic representation of components of a rotor 1 . The rotor 1 can be used for an electric machine. In particular, the rotor 1 be used in a wide variety of electrical machines. For example, the rotor 1 Be part of a commutator machine or a synchronous machine. It is also conceivable that the rotor is a squirrel-cage rotor.

The rotor 1 consists of magnets 2 , especially from a variety of magnets 2 , and from a rotor core 3 . The magnets 2 are in the rotor core according to their magnetic poles 3 arranged.

For example, have the rotor 1 and the rotor core 3 a cylindrical or cylinder-like shape. In particular, the rotor 1 correspondingly along an axis of rotation 11 rotatable or rotatable.

In the 1B Figure 3 is a schematic plan view of the rotor 1 shown. It can be seen that in the center of the rotor 1 a wave can be absorbed. In particular, it can be seen here that the rotor 1 and thus the rotor core 3 several magnetic pockets 5 exhibit. In these magnetic pockets 5 can use the magnets 2 be recorded or positioned therein.

Around the rotor 1 to be able to manufacture or assemble or assemble, several sheet metal layers 6th to the rotor core 3 put together. This is in the 1C to see. In particular, the multiple sheet metal layers 6th Arranged or stacked in such a way that individual sheet metal cuts 7th in the several sheet metal layers 6th at least one magnetic pocket 8th for a magnet 9 form. In particular, the individual sheet metal layers have this 6th or sheet metal segments predetermined sheet metal cuts 7th on. The sheet metal cuts 7th have an opening or a notch or a groove in the individual sheet metal layers 6th on. In other words, the individual sheet metal layers 6th stacked on top of each other so that the individual sheet metal cuts 7th rest on top of each other and form a common opening or an area that acts as a magnet receiving pocket 8th can be designated. In particular, the individual sheet metal layers 6th according to the axis of rotation 4th arranged coaxially. In particular, the sheet metal layers 6th equiangularly corresponding to the axis of rotation 4th stacked.

When inserting or bringing in the magnet 9 in the at least one magnetic pocket 8th creates a gap 10 between the magnet 9 and the at least one side wall 11 the at least one magnetic pocket 8th . In particular, there is a gap in each of the areas between the magnets 9 and the magnetic pocket 8th which in relation to the axis of rotation 4th is arranged vertically or vertically.

Now to the magnet 9 for later use of the rotor 1 To be able to fix it sufficiently in the electrical machine, the individual sheet metal layers 6th twisted or shifted to each other. The sheet metal layers 6th corresponding to a direction of rotation 12th twisted. This will make the individual sheet metal layers 6th or sheets alternately twisted in such a way that the magnet is triggered by sheet metal protrusions or a clamping force 9 is fixed or held. In particular, this is done by twisting the gap 10 so reduced that the at least one side wall 11 or several side walls 11 on the magnet 9 and through the twisted sheet metal layers 6th over the at least one side wall 11 a clamping force on the magnet 9 works. Thus, by twisting or shifting the individual or several sheet metal layers 6th or the entire laminated rotor core 3 without the use of filler material the magnet 9 fixed. By reducing the air gap or gap 10 the advantages already mentioned can be used. The reduced or reduced gap is particularly advantageous 10 in that a recording, an inhibition or a suppression of all in the operation of the rotor 1 resulting forces can be carried out. Thus the rotor can 1 operated more efficiently.

There is also an advantage in the distribution of the surface stress or the transverse forces due to the offset of the sheet metal layers 6th to each other. Due to the reduced air gap or gap 10 the result is an improved heat dissipation of the rotor and a better design of a magnetic field of the magnet 9 .

In particular, individual or all sheet metal layers of the plurality of sheet metal layers can 6th are twisted against each other at the same time. In other words, the multiple sheet metal layers 6th alternately to the right or to the left according to the axis of rotation 4th rotated so that the magnet 9 and especially all magnets 2 be fixed. For example, after the sheet metal layers have been rotated against each other at the same time 6th Check immediately after turning whether the magnet 9 is sufficiently fixed. If this is not the case, individual sheet metal layers can be rotated afterwards or again accordingly until the magnet 9 sufficient in the magnetic pocket 8th is fixed.

For example, the 2A and 2 B an embodiment of a rotating device 13th . The 2A shows this, for example, a plan view, and the 2 B shows a side view. In particular, the laminated rotor core 3 consisting of the sheet metal layers 6th and the magnet 2 in a holding device 14th introduced or received or held.

For example, in the 2 B to see that a tool 15th the turning device 13th for twisting the several sheet metal layers 6th in at least one indentation 16 along an outer perimeter 17th one sheet metal layer of the several sheet metal layers 6th is inserted. Thus, over the indentation 16 or the existing openings in the sheet metal layers 6th by means of the tool 15th a rotation of one or more sheet metal layers can be carried out. This can be done, for example, while standing or lying down. The twist or Interlocking of the several sheet metal layers 6th can by moving the rotor 1 or the rotating device 13th respectively. For example, it is the rotating device 13th an automated manufacturing machine for the rotor 1 . With the tool 15th it can be, for example, a mechanical single finger or a template or a comb or a rake or a single finger template. With the help of the tool 15th the turning device 13th can precisely twist the several sheet metal layers 6th to fix the magnet 9 be performed.

For example, the 3A and 3B another embodiment of the rotating device 13th . For example, the 3A a top view and the 3B a side view. In this exemplary embodiment, the sheet metal layers are rotated automatically 6th by using the tool 15th the sheet metal layers 6th along their outer contour 17th be twisted. In this exemplary embodiment, it is the tool 15th about rollers or rollers. The sheet metal layers are thus twisted 6th in this embodiment by a rotary movement of the rollers as a tool 15th along the direction of rotation 12th .

For example, the rotating device 13th have a monitoring device by means of which the turning process can be continuously monitored. The turning path of the sheet metal layers is particularly important here 6th , a force or a combination of distance and force is continuously monitored.

For example, the sheet metal layers are twisted 6th as a function of a predetermined twist angle and / or a predetermined twisting force. For example, this can be done by the rotating device 13th being controlled. For example, the angle of rotation of the sheet metal layers 6th can be absolutely specified as an angular dimension or the rotation can also be controlled or regulated in terms of force application, so that the rotation is ended when a predeterminable counterforce is reached. This can prevent a strong twisting of the sheet metal layers 6th Damage to the magnet 9 or on the rotor core 3 arise.

Another possibility for the design of the rotating device 13th will now be described. First of all, the laminated rotor core 3 consisting of the sheet metal layers 6th and the magnet 2 in the holding device 14th taken horizontally or vertically. With the help of the indentations 16 , which are formed, for example, as grooves, elevations or lugs, can by means of the tool 15th , which in this case is designed as a single finger stencil or stencil, a rotation of one or more sheet metal layers 6th can be achieved. This can be done while the rotor core stack is standing or lying down 3 respectively. The twisting or interlocking of the sheet metal layers 6th is done by moving the rotor 1 or the tool 15th . This process can also be monitored with the monitoring device. With the help of the template, single or multiple sheet metal layers 6th easily twisted.

For example, several or all sheet metal layers can be rotated against each other at the same time using a kind of comb, or individual layers can also be rotated using individual mechanical fingers. For example, all sheet metal layers can be used in a first process step 6th can be rotated together, and then, depending on requirements, individual sheet metal layers 6th subsequently rotated or re-rotated. This can be of advantage if, due to production inaccuracies in a sheet metal cut or a magnet, the angle of rotation of the sheet metal layers 6th not all are the same. A correction of manufacturing tolerances can thus be carried out here.

For example, individual mechanical torsion fingers of a comb can be spring-mounted so that each of these torsion fingers can individually absorb a counterforce to the spring force and gives way when a certain counterforce is reached, so that the sheet metal layer moved with this finger cannot be rotated any further. Thus, even with a comb or a template and many individual mechanical torsion fingers, different angles of rotation of the individual sheet metal layers can nevertheless be achieved 6th will be realized. Instead of spring mounting the individual mechanical fingers, this can also be controlled or regulated differently, for example actively.

To the magnet 9 To be able to fix sufficiently, can when twisting one sheet metal layer of the several sheet metal layers 6th in the direction of rotation 2 a sheet metal layer adjacent to this sheet metal layer is held or in a direction of rotation 2 can be twisted in the opposite direction. The twisting of one sheet metal layer of the several sheet metal layers thus takes place 6th always with a turning force and a holding force or by means of two opposing turning forces.

At a later assembly process of the rotor 1 with a stator, predetermined air gaps are advantageous, so that through the indentations 16 synergy effects are created for this purpose.

Another possibility to perform an automatic turning process of the sheet metal layers 6th is in the 4A to 4C shown.

This is in the 4A a top view of the rotor core 3 shown. The sheet metal layers 6th and in particular the laminated rotor core 3 openings 18th exhibit. At the openings 18th it is in particular openings or holes or bores within the outer circumference 17th the sheet metal layers 6th . In other words, it is the openings 18th around holes or bores along the axis of rotation 4th . In particular, a depth or a length dimension of the openings 18th with respect to the axis of rotation 4th vary.

In this exemplary embodiment, the tool 15th be a mandrel or a rod or a pencil. In this case, the tool just described can be used 15th into the opening 18th be plugged in or inserted. In particular, multiple tools 15th in several openings 18th inserted. An improved force distribution when twisting can thus be achieved. In the 4B is an inserted tool in an opening 18th shown. Where in this example is the tool 15th over several layers 6th inserted. In particular, depending on the application, the tool 15th be sandwiched between two or five or ten layers. This can depend on the manufacturing process or the design of the rotor 1 vary. In the 4C a side view of the tool is shown for this case. Here is the tool in this case 15th similar to a mandrel or a nail or a screw.

The turning process can be similar to the possibilities or embodiments of the turning device already described 13th be used. Another way of twisting the sheet metal layers 6th by means of the rotating device 13th is twisting through differently perforated sheet metal layers 6th and the alignment by means of the tool 15th as a pen. The individual sheet metal layers 6th be punched a few degrees counterclockwise. This can in particular refer to an end position or end position of the assembled rotor 2 are related, in which the inserted magnet 9 was pinched by twisting. First the magnets are inserted into the magnet holding pockets and then pins are inserted as tools 15th into the cutouts, making the sheet metal layers 6th be twisted and the magnet 9 is fixed. The now twisted sheet metal layers can then be used 6th be permanently fixed or secured. For example, the sheet metal cuts 7th already have corresponding lugs or tabs for the alternating sheet metal layers 6th are different and are then displaced by a block-like or cuboid-shaped rotating device as a tool 15th align straight and thus the sheet metal layers 6th are twisted and thus a clamping structure for fixing the magnet 9 arise.

The 5 shows an exemplary process flow for assembling the rotor 1 . The possibilities for rotating the sheet metal layers already described above can be used here 6th must be taken into account.

In an optional first step S1 the multiple sheet metal layers 6th stacked or arranged one above the other. This creates the loose rotor core 3 . The individual sheet metal layers can be discharged differently. In order to be able to align the individual sheet metal layers later, the individual sheet metal layers can be taken along. These can be raised, such as a nose, or lowered, such as a groove. There is also the possibility of securing the entrainment via the shape of the sheet metal layers. For example, the sheet metal layers 6th can be made concave or convex.

In a subsequent, optional second step S2 the multiple sheet metal layers 6th arranged one above the other in such a way that the at least one magnet receiving pocket 8th is formed. In this case, an alignment of the sheet metal layers is particularly important 6th possible.

In a subsequent exemplary third step S3 become the magnets 2 and especially the magnet 9 loosely in the recess or magnetic pocket 8th inserted.

In a subsequent, optional fourth step S4 the individual sheet metal layers 6th or all sheet metal layers 6th twisted or interlaced, whereby by twisting or interlacing the sheet metal layers 6th the loose magnet 9 in the magnetic pocket 8th is fixed and in particular clamped. For example, the twisting of the sheet metal layers 6th as previously described by means of a single mandrel or a tool 15th over one or more sheet metal layers 6th or sheet metal layers take place. Another possibility is to securely rotate the sheet metal layers by means of a frictional connection, i.e. friction 6th perform. This can cause jamming of the sheet metal layers 6th be done by jamming individual layers between forks or wheels.

An execution of the twisting or twisting by means of differently punched sheet metal layers can also be implemented 6th in relation to the sheet metal layers. A pin can be inserted through a punched hole so that the sheet metal layers are related to the axis of rotation 4th can be rotated.

In particular, the described embodiments of the rotating device 13th both for the entire rotor core 3 as well as for the individual sheet metal layers 6th will be realized. When punching out or remaining material, such as noses or teeth, attention must be paid to symmetry or the compensation of material defects or material transitions in order to achieve the highest possible balance quality of the rotor 1 to obtain.

In an optional subsequent fifth step S5 can permanently secure the twisted sheet metal layers 6th respectively. In other words, the individual sheet metal layers 6th be secured in a twisted or entangled state by welding, clamping or other methods. Thus, the rotor core 3 and especially the rotor 1 can be used permanently.

List of reference symbols

1

rotor

2

Magnets

3

Rotor core

4th

Axis of rotation

5

Magnetic pockets

6th

several sheet metal layers

7th

Sheet metal cut

8th

Magnetic pocket

9

magnet

10

gap

11

Side wall

12th

Direction of rotation

13th

Turning device

14th

Holding device

15th

Tool

16

indentation

17th

Outer circumference

18th

opening

S1 to S5

first to fifth step

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 102016211711 A1 [0004]
• DE 102011078054 A1 [0004]
• DE 102010044521 A1 [0005]
• DE 102015007138 A1 [0005]
• DE 102014017305 A1 [0005]
• DE 102014019217 A1 [0006]

Claims (6)

Method for assembling a rotor (1) of an electrical machine, wherein - several sheet metal layers (6) are joined together (S1) to form a rotor core (3) of the rotor (1), - the several sheet metal layers (6) are arranged one above the other in such a way that individual Sheet metal cuts (7) in the multiple sheet metal layers (6) form at least one magnet receiving pocket (8) for a magnet (9) of the rotor (1) (S2), and - the magnet (9) is inserted into the at least one magnet receiving pocket (8) , whereby a gap (10) between the magnet (9) and at least one side wall (11) of the at least one magnet receiving pocket (8) is created (S3), characterized in that - the multiple sheet metal layers (6) are rotated relative to one another, whereby the gap (10) is reduced so that the magnet (9) is fixed in the magnet receiving pocket (8) (S4). Procedure according to Claim 1 , characterized in that individual or all sheet metal layers (6) are rotated against each other at the same time, after the rotation of the sheet metal layers (6) it is checked whether the magnet (9) is fixed in the at least one magnet receiving pocket (8). Procedure according to Claim 1 or 2 , characterized in that the twisting of the plurality of sheet metal layers (6) is controlled as a function of a predetermined twisting angle and / or a predetermined twisting force. Method according to one of the preceding claims, characterized in that when a sheet metal layer of the plurality of sheet metal layers (6) is rotated in one direction of rotation (12), a sheet metal layer adjacent to the one sheet metal layer is held or rotated in a direction opposite to the direction of rotation (12). Method according to one of the preceding claims, characterized in that the rotation of the plurality of sheet metal layers (6) is carried out by means of a turning device (13), and the plurality of sheet metal layers (6) are received in a holding device (14) of the turning device (13), wherein a tool (15) of the rotating device (13) for rotating the plurality of sheet metal layers (6) is inserted into at least one indentation (16) along an outer circumference (17) of a sheet metal layer of the plurality of sheet metal layers (6), or into an opening (18) within of the outer circumference (17) is introduced into one or more of the sheet metal layers (6). Rotor (1) for an electrical machine, with a laminated rotor core (3), the rotor (1) being produced by means of a method according to one of the preceding claims.

Images