WO2021259411A1

WO2021259411A1 - Rotor for an electric rotation machine, method for producing the rotor, and electric rotation machine

Info

Publication number: WO2021259411A1
Application number: PCT/DE2021/100456
Authority: WO
Inventors: Julian UMLANDT
Original assignee: Schaeffler Technologies AG & Co. KG
Priority date: 2020-06-26
Filing date: 2021-05-26
Publication date: 2021-12-30
Also published as: DE102020116849A1

Abstract

The invention relates to a rotor for an electric rotation machine, to a method for producing the rotor, and to an electric rotation machine comprising the rotor. The rotor (1) for an electric rotation machine comprises a rotor shaft (10), at least one rotor body (20) which is connected to the rotor shaft (10) and which has at least one laminated core (25), a first axial contact element (23) on the rotor shaft (10) on a first axial side (21) of the rotor body (20) for blocking the translational degree of freedom of the rotor body (20) along the rotational axis (13) of the rotor (1) in a first direction (24), and a sleeve (30) which is fixed to the rotor shaft (10) on a second axial side (22) lying axially opposite the first axial contact element (23) for blocking the translational degree of freedom of the rotor body (20) along the rotational axis (13) of the rotor (1) in a second direction (34) opposite the first direction, wherein a rotor of a rotor position sensor device (40) is fixed on the sleeve (30). The aforementioned rotor, the method for producing the rotor, and the electric rotation machine comprising the rotor ensure a simple assembly and an axial fixation of all of the rotor components on the shaft in an inexpensive and variable manner while requiring little installation space.

Description

Rotary electric machine rotor. Method of manufacturing the rotor and electric rotary machine

The invention relates to a rotor of an electric rotary machine, a method for manufacturing the rotor and an electric rotary machine with the rotor.

From the prior art, electrical drive machines are known in many industrial applications, which are also increasingly being used in the automotive industry. Such a machine comprises a stator and a rotor which can be rotated in relation to it. The rotor usually comprises a rotor shaft, balancing plates, Ro torblechpakete and magnets. The magnets are generally fixed in the rotor lamination packages.

Rotors of rotor position sensors require a firm fixation in relation to the rotor in order to be able to detect the respective angular position of the rotor or individual components of the rotor with high accuracy. It is customary to fix the rotor of the rotor position sensor on or on the shaft firmly connected to the rotor body. However, this type of arrangement results in assembly costs after the individual components of the rotor have been assembled on the shaft. Furthermore, this design requires a corresponding axial space requirement.

The invention is therefore based on the object of providing a rotor of an electrical Rota tion machine, a method for producing the rotor and the rotor encompassing electrical rotating machine available that simple assembly and axial securing of all rotor components on the shaft in low-cost ger as well ensure variable way with a small space requirement.

This object is achieved by the rotor according to claim 1 and by the method for producing a rotor according to claim 8. Advantageous configurations of the rotor are specified in the dependent claims 2 to 7. An advantageous embodiment of the method for producing the rotor defines dependent claim 9. In addition, an electric rotary machine with the rotor according to claim 10 is made available.

The features of the claims can be combined in any technically meaningful manner, in which case the explanations from the following description and features from the figures can also be used, which include additional embodiments of the invention.

In the context of the present invention, the terms “axial” and “circumferential direction” always relate to the axis of rotation of the rotor.

The invention relates to a rotor of an electrical rotating machine, comprising a rotor shaft and, connected to the rotor shaft, at least one rotor body which has at least one laminated core. Furthermore, the rotor on the rotor shaft comprises a first axial contact element on a first axial side of the laminated core to block the translational degree of freedom of the rotor body along the axis of rotation of the rotor in a first direction, and on a second axial contact element axially opposite the first axial contact element axial side a sleeve fixed on the rotor shaft to block the translational degree of freedom of the rotor body along the axis of rotation of the rotor in a second, opposite direction to the first direction. A rotor of a rotor position sensor device is fixed on the sleeve.

The sleeve is designed essentially as a hollow cylinder and is arranged on the rotor shaft coaxially to the axis of rotation of the rotor shaft.

In addition to the components of the rotor body mentioned, it can also have one or more balancing disks, such as a first balancing disk between the first axial contact element and the laminated core and / or a second balancing disk between the laminated core and the sleeve.

A sleeve can be used that is inexpensively manufactured from a tubular raw material such as tubular raw material according to EN10305-2.

The laminated core of the rotor is also understood to mean a so-called rotor stack, which is designed as a stack arrangement of individual laminations. The sleeve thus forms a second axial contact element on the axially opposite side from the first axial contact element.

If necessary, one or more balancing disks can also be arranged on the rotor shaft as components of the rotor body. In this case, the first axial contact element and the sleeve are used to block the axial translational degree of freedom of one or more laminated cores and also of the balancing disks.

Correspondingly, in this embodiment, the first axial contact element and / or the sleeve do not rest directly on a laminated core, but instead block its translational degree of freedom indirectly by contacting a balancing disk. With the sleeve, an efficient, axial securing of rotor components is realized on the rotor shaft. Installation can be carried out in a simple and efficient manner. Tolerances in the axial dimensions of the individual rotor components arranged axially one behind the other can be compensated for by shifting the sleeve slightly. Due to the arrangement of the rotor of the rotor position sensor device on the sleeve used for axial fixation, there is a saving in axial installation space compared to conventional embodiments.

In an advantageous embodiment it is provided that the sleeve is caulked with the rotor shaft.

In particular, the caulking is implemented in an axial end region of the rotor shaft. The individual areas of the sleeve are axially defined in such a way that correct caulking is possible in all possible axial positions on the rotor shaft, which can result from the component tolerances of the individual rotor parts. Alternatively, the sleeve can also be means of another mechanical connection, such as. B. a welded connection, be connected to the rotor shaft.

Furthermore, the rotor of the rotor position sensor device can also be connected to the sleeve by means of a cross-compression connection.

A transverse interference fit is designed in such a way that the sleeve is heated and / or the shaft is cooled. As a result, the sleeve or the shaft expands shrinks in its outer dimensions, so that the sleeve can be pushed onto the shaft in a simple manner and with less effort. When the temperature is then equalized, there is a strong interference fit between the outside of the shaft and the inside of the sleeve, so that the sleeve is fixed on the shaft.

Alternatively, the rotor of the rotor position sensor device is pressed cold onto the sleeve.

In both procedures, a press fit is produced between the rotor of the rotor position sensor device and the sleeve, which fixes the rotor of the rotor position sensor device in the circumferential direction as well as in the axial direction.

In an advantageous embodiment it is provided that the radial outer side of the sleeve is designed essentially cylindrical at least in the area of the seat of the rotor of the rotor position sensor device in order to easily allow an axial displacement of the essentially annular rotor of the rotor position sensor device in the To enable assembly for the purpose of adaptation to a predetermined axial position. This enables an axial tolerance compensation due to the tolerance chain of the individual components to be made possible in an efficient manner.

For a further axial tolerance compensation component of the rotor body can be at least one disc spring which is arranged axially between the axial contact element and the sleeve. The disc spring enables a further axial tolerance compensation of the individual elements of the rotor body as well as the realization of a constantly acting axial preload force.

In particular, the sleeve can sit on the rotor shaft with a press fit. The press fit should be implemented at least in the axial section of the sleeve in which the rotor of the rotor position sensor device is also seated on the sleeve.

This serves to ensure that the rotor of the rotor position sensor device can be fixed on or on the sleeve with the required axial positional accuracy. The press fit also ensures accuracy in terms of concentricity and coaxiality. Furthermore, a press fit between the sleeve and the rotor shaft can be carried out axially adjacent to and adjacent to the caulking in order to avoid an inadmissibly large expansion of the sleeve in the axial area of the arrangement of the rotor of the rotor position sensor device.

However, this press fit is advantageously carried out with a smaller oversize than the press fit between the rotor of the rotor position sensor device and the sleeve.

The respective length of fit between the rotor shaft and the sleeve is to be made as small as possible in order to be able to keep the forces required to slide the sleeve onto the rotor shaft low when the sleeve is being assembled.

In the axial end region or in a first length section of the sleeve, which is used to rest on the rotor body, the radial inside of the sleeve can be spaced from the radia len outside of the rotor shaft. This means that the sleeve is not seated on the rotor shaft with an interference fit, at least in this axial section, but with a clearance fit.

This means that the sleeve has on its radial inside at least one area with which it is seated on the shaft by means of a press fit, and at least one other area which is spaced apart from the radial outside of the shaft, so that at least in this spaced-apart area reduced or no frictional forces have to be overcome when sliding the sleeve onto the shaft during assembly. Overall, the arrangement of the rotor of the rotor position sensor device on the sleeve allows an axially space-saving design of the rotor with ver reduced assembly costs. The sleeve can be caulked with the shaft in a simple and inexpensive manner.

In the preferred embodiment, in which a rotationally symmetrical rotating part and / or a pipe section is used as the sleeve, the cylindrical contour of the sleeve can correspondingly be used to arrange different rotors of rotor position sensor devices. Due to the fact that, in a preferred embodiment, the sleeve is only seated on the shaft by means of a press fit, when appropriate diameter ratios are set between the sleeve and the Shaft in an easy way to adapt the sleeve and / or the shaft to each other. Likewise, sleeves of different axial lengths can be provided to compensate for different tolerances and / or to be fixed at different axial positions on the shaft, in particular caulked will.

Another aspect is a method for producing the rotor of an electric rotating machine, in which a rotor shaft and elements of a rotor body with at least one laminated core to be connected to the rotor shaft are provided, along the rotor shaft a first axial contact element for blocking the translational degree of freedom of the laminated core the axis of rotation of the rotor is arranged in a first direction, on the rotor shaft the laminated core is arranged, on the second axial side axially opposite the first axial contact element to block the translational degree of freedom of the laminated core along the axis of rotation of the rotor in a second, the A sleeve is fixed on the rotor shaft in the opposite direction to the first direction, and a rotor of a rotor position sensor device is fixed on the sleeve.

If necessary, balancing disks can also be arranged on the rotor shaft as components of the rotor body.

In detail, the order in which the individual elements of the rotor body are assembled can be such that, for example, a first balancing disk is pushed onto the shaft, then one or more laminated cores, so-called rotor stacks, are pushed onto the shaft and then, if necessary, a second balancing disk is attached the last stack of sheets is pushed. If necessary, one or more disc springs can also be integrated into the rotor body designed in this way. The sleeve is also pushed onto the shaft and rests axially on the rotor body. In an advantageous embodiment it is provided that the rotor of the rotor position sensor device is then fixed on the sleeve by means of a transverse interference fit.

In this case, it is not mandatory to adhere to the specified sequence when fixing the rotor of the rotor position sensor device, but the rotor of the rotor position sensor device can also be first fixed on the sleeve and then the sleeve can be arranged on the rotor shaft. The sleeve is therefore located between the rotor shaft and the rotor of the rotor position sensor device.

This means that when the rotor is installed, the rotor position sensor is installed essentially at the same time.

In an advantageous embodiment of the method for producing the rotor, axial tolerance compensation is carried out during assembly by pushing the elements of the Rotorkör located axially between the axial contact element and the sleeve in the direction of the axial contact element until as a block, they are prevented from further displacement by the first axial contact element, and the bushing is fixed on the rotor shaft with the bushing against the rotor body.

This enables an axial tolerance compensation in the tolerance chain of the individual rotor components.

This means in particular that the sleeve is placed against the element adjacent to it and is caulked with the rotor shaft in this axial position.

The sleeve has a sufficient axial length that makes it possible to vary the axial position of the sleeve on the rotor shaft in a certain length section and still caulk the Ver at a defined axial position on the rotor shaft or some other mechanical connection such . B. to realize a weld connection between the sleeve and the rotor shaft.

This prevents play between the individual elements and between the axial contact element and the sleeve due to manufacturing tolerances. The caulking is carried out in a defined axial position on the rotor shaft, in which at least one prefabricated shaped element, such as a groove, is already located in the rotor shaft for the caulking. Point deformations of the sleeve can be impressed in the groove.

In an advantageous embodiment, there is a groove on the rotor shaft end into which sleeve material is pressed after the axial assembly force has been applied, radially and partially by means of metal stamping. This pressing process is called caulking. A high number of caulking points distributed around the circumference prevents with a radial expansion of the sleeve in the area of the fit for the rotor of the rotor position sensor device and increases the capacity to absorb axial forces.

In addition, an electric rotating machine is made available which comprises the rotor.

The invention described above is explained in detail below against the relevant technical background with reference to the accompanying drawings, which show preferred embodiments. The invention is in no way limited by the purely schematic drawings, it being noted that the exemplary embodiments shown in the drawings are not limited to the dimensions shown. It is shown in

Figure 1: the rotor in view from the side,

Figure 2: the rotor in perspective view,

Figure 3: the rotor in sectional view, and

FIG. 4: a partial area of the rotor in an enlarged sectional view.

First, the general structure of the rotor 1 will be discussed. As can be seen from FIGS. 1 and 2, the rotor 1 comprises a rotor shaft 10 which is designed to rotate about an axis of rotation 13. A rotor body 20 is formed on the rotor shaft 10 coaxially to the axis of rotation 13. In the embodiment presented here, this comprises two sheet metal stacks 25 lying next to one another, which are also referred to as rotor stacks. On a first axial side 21 of the rotor body 20, the latter is limited by a first balancing disk 26 which rests against a first axial contact element 23 which is formed by the rotor shaft 10. This first balancing disk 26 thus forms a first axial side 21 of the rotor body 20. On the second axial side 22 axially opposite the first axial side 21, the rotor body 20 comprises a second balancing disk 27, which likewise rests against one of the laminated cores 25. Movement of the rotor body 20 or its individual components in the first direction 24 is thus prevented by the first axial contact element 23. Axially opposite the first axial contact element 23, the rotor comprises an essentially hollow cylinder-shaped sleeve 30, which here fulfills the function of a second axial contact element. The sleeve 30 is firmly caulked to the rotor shaft 10 in an axial end region 11 of the rotor shaft 10 by means of several caulking points 50 implemented on its circumference. In this way, the sleeve 30, as a second axial contact element, blocks an axial movement of the rotor body 20 or its individual components along the illustrated second direction 34.

The rotor of the rotor position sensor device 40 is seated radially on the outside on the sleeve 30. This is designed essentially in the form of a ring. It can be seen that the rotor of the rotor position sensor device 40 is arranged axially close to the rotor body 20, due to the fact that it is arranged on the sleeve 30 which is used to mount or fix the rotor body 20. In FIGS. 3 and 4, the specific structure of the rotor 1 in the axial end region 11 of the rotor shaft 10, in which the rotor of the rotor position sensor device 40 is arranged, can be seen in the sectional representations. It can be seen here that a groove 12 is made in the radial outside of the rotor shaft 10, into which caulking points 50 in the sleeve 30 engage. This prevents in particular an axial displacement of the sleeve 30 in relation to the rotor shaft 10 and consequently also an axial displacement of the rotor of the rotor position sensor device 40. The mechanical connection between the sleeve 30 and the rotor of the rotor position sensor device 40 takes place in the embodiment shown here by means of a transverse interference fit, which due to the realized press fit, an axial fixation as well as a circumferential fixation of the rotor of the rotor position sensor device 40 the sleeve 30 causes. The sleeve 30 is also fixed by means of a press fit 60 on the radial outside of the rotor shaft 10. These fastening methods have the advantage of low effort and a light and space-saving design.

It can be seen in particular from FIG. 4 that the press fit 60 between the sleeve 30 and the rotor shaft 10 is not implemented over the entire axial length of the sleeve 30. The sleeve 30 comprises a first length section 31, in which the radia le inside of the sleeve 30 is spaced apart from the radial outside of the rotor shaft 10 or is designed with a radial play in order to prevent the Slide the sleeve 30 onto the rotor shaft 10 to minimize frictional forces. In this case, the sleeve 30 in this first longitudinal section 31 is designed with an increased wall thickness or radial extension in order to achieve a large contact surface and rigidity when the sleeve 30 is pushed onto the rotor shaft 10 and a compressive force is exerted on the second balancing disk 27.

In a second length section 32 of the sleeve 30 axially adjacent to the first length section 31, the sleeve 30 is fixed with the aforementioned press fit 60 on the rotor shaft 10. This is at the same time the section which is used to position the rotor of the rotor position sensor device 40. Due to the press fit 60 between the sleeve 30 and the rotor shaft 10, there are exact geometrical dimensions that lead to low unbalance in this second length section 32, and offer a correspondingly high running quality for the rotor of the rotor position sensor device 40. Adjacent to the second length section 32 and facing the axial end region 11 of the Ro gate shaft 10, the sleeve 30 has a third length section 33.

In this third length section, the caulking of the sleeve 30 with the rotor shaft 10 is realized by means of the caulking points 50 clearly visible in FIG , whereby the interference fit is advantageously not as great as in the second length section 32. Alternatively, a clearance fit is implemented in this axial section, depending on the force acting during assembly and a change in the second length section 32 after caulking adjusting deformation.

It can be seen overall that the second length section 32 simultaneously forms the seat 61 of the rotor of the rotor position sensor device 40. It can be seen in particular from FIG. 4 that the positioning of the rotor of the rotor position sensor device 40 on the sleeve 30 which is used to fix the components of the rotor body 20 can save axial installation space in an efficient manner.

With the rotor proposed here, the method for producing the rotor and the electric rotary machine comprising the rotor, a simple Mon days and axial securing of all rotor components on the shaft is guaranteed in an inexpensive and variable manner with a small footprint. Reference list

I rotor

10 rotor shaft

I I axial end area of the rotor shaft

12 groove

13 axis of rotation

20 rotor bodies

21 first axial side

22 second axial side

23 first axial contact element

24 first direction

25 laminated core

26 First balancing disc

27 Second balancing disc

30 sleeve

31 First length section

32 Second length section

33 Third length section

34 second direction

40 Rotor of the rotor position sensor device

41 Cross interference fit

50 caulking point

60 interference fit

61 Seat of the rotor of the rotor position sensor device

Claims

1. Rotor (1) of an electric rotating machine, comprising a rotor shaft (10) and connected to the rotor shaft (10) at least one rotor body (20) which has at least one laminated core (25), and on the rotor shaft (10) at egg ner first axial side (21) of the rotor body (20) a first axial contact element (23) for blocking the translational degree of freedom of the Ro torkörpers (20) along the axis of rotation (13) of the rotor (1) in a first direction (24), and on one of the first axial contact element (23) axially opposite the second axial side (22) a on the rotor shaft (10) fixier te sleeve (30) to block the translational degree of freedom of the Rotorkör pers (20) along the axis of rotation (13) of the Rotor (1) in a second direction (34) opposite to the first direction, characterized in that a rotor of a rotor position sensor device (40) is fixed on the sleeve (30).

2. Rotor according to claim 1, characterized in that the sleeve (30) is caulked with the rotor shaft (10).

3. Rotor according to one of the preceding claims, characterized in that the rotor of the rotor position sensor device (40) is connected to the sleeve (30) by means of a cross press connection.

4. Rotor according to one of the preceding claims, characterized in that part of the rotor body (20) is at least one disc spring which is axi al between the first axial contact element (23) and the sleeve (30) angeord net.

5. Rotor according to one of the preceding claims, characterized in that the sleeve (30) sits with a press fit (60) on the rotor shaft (10).

6. Rotor according to claim 5, characterized in that the press fit (60) is realized at least in the axial section of the sleeve (30) in which the rotor of the rotor position sensor device (40) is seated on the sleeve (30).

7. Rotor according to one of the preceding claims, characterized in that in a first length section (31) of the sleeve (30), which is used to rest on the rotor body (20), the radial inside of the sleeve (30) from the radia len outside the rotor shaft (10) is spaced apart.

8. A method for manufacturing a rotor of an electric rotating machine according to any one of claims 1 to 7, in which

-a rotor shaft (10) and elements of a rotor body (20) to be connected to the rotor shaft (10), comprising at least one laminated core (25), are provided,

- A first axial contact element (23) for blocking the translational degree of freedom of the rotor body (20) along the axis of rotation (13) of the rotor (1) in a first direction (24) is arranged on the rotor shaft (10),

- At least one laminated core (25) is arranged on the rotor shaft (10),

- On the first axial contact element (23) axially opposite two th axial side (22) for blocking the translational degree of freedom of the rotor body (20) along the axis of rotation (13) of the rotor (1) in a two-th, opposite to the first direction Direction (34) a sleeve (30) is fixed on the rotor shaft (10), and

- A rotor of a rotor position sensor device (40) is fixed on the sleeve (30).

9. A method for producing a rotor according to claim 8, characterized in that an axial tolerance compensation is carried out during assembly by the components of the rotor body (30) located axially between the first axial contact element (23) and the sleeve (30). 20) are pushed so far in the direction of the first axial contact element (23) until they are a block of the first axial contact element (23) at a further shift. are prevented, and with the sleeve (30) resting on the rotor body (20), the sleeve (30) is fixed on the rotor shaft (10).

10. An electric rotary machine, comprising a rotor (1) according to any one of claims 1 to 7.