CN213754129U

CN213754129U - Motor, rotor for motor and vehicle with motor

Info

Publication number: CN213754129U
Application number: CN201990000399.XU
Authority: CN
Inventors: H·弗雷利希; R·霍夫曼
Original assignee: Vitesco Technologies GmbH
Current assignee: Vitesco Technologies GmbH
Priority date: 2018-01-19
Filing date: 2019-01-15
Publication date: 2021-07-20
Anticipated expiration: 2029-01-15
Also published as: DE102018200865A1; DE102018200865B4; WO2019141690A1

Abstract

The utility model relates to a rotor (10) for motor, it has: a set of sheet material (12) surrounding the cavity; a first end face flange (16) and a second end face flange (18), wherein the first end face flange (16) and the second end face flange (18) are arranged on an end side of the sheet material group (12) in an axial direction of the rotor (10) and are configured for rotatably supporting the rotor (10) about a rotor axis (22) of the rotor; a traction element (24) guided through the sheet metal pack (12) and axially connecting the first end flange (16) to the second end flange (18) and prestressing the first end flange: and a centering element (28) guided through the cavity, the centering element interconnecting the first end face flange (16) and the second end face flange (18).

Description

Motor, rotor for motor and vehicle with motor

Technical Field

The invention relates to a rotor for an electric machine, preferably for a permanently excited synchronous machine, the torsional and/or flexural rigidity of which is increased and is therefore of low deformation design, in particular at high rotational speeds.

Background

In principle, rotors of electrical machines, in particular permanently excited synchronous machines, are known. In the known electric machine, permanent magnets are arranged and fastened in the rotor. The rotor has a rotor body that is constructed on a plurality of sheets of sheet material and assembled into a sheet material pack. Each of the plates of magnetic steel is stamped into the same shape and then assembled, with the individual sheets isolated from each other. The group of metal sheets has a central opening which receives a drive shaft which connects the group of metal sheets to the drive shaft in a rotationally fixed manner, for example by heat shrinking. The individual permanent magnets forming the poles of the rotor are held in stamped openings in a rotor or sheet metal stack of cylindrical design.

The set of plates performs the function of forming a magnetic field and the function of a support structure that holds the permanent magnets in their position. The sheet metal assembly also has the function of transmitting torque from the sheet metal assembly to the rotor shaft.

Due to the rotation of the rotor, in particular at very high rotational speeds, vibrations and relative movements of the individual metal sheets occur under the influence of centrifugal forces, so that the surface of the metal sheet pack changes and the connection of the permanent magnets fastened to this surface can be damaged. At high rotational speeds, the sheet metal pack therefore exhibits a strong anisotropy, as a result of which the system can be easily vibrated at low frequencies in the operating range. Such known rotors therefore have only a limited potential for increasing the rotational speed or diameter while the rotational speed remains unchanged.

SUMMERY OF THE UTILITY MODEL

The object of the present invention is to provide a rotor for an electric machine, the torsional and/or bending stiffness of which is increased, so that torque can be reliably transmitted, in particular at high rotational speeds.

This object is achieved by the object of the independent claim 1. Advantageous embodiments of the invention are given in the dependent claims, the description and the drawings, wherein each feature can form an aspect of the invention individually and in combination.

According to the utility model discloses, be provided with the rotor that is used for the motor, it has: a set of sheet material surrounding the cavity; a first end face flange and a second end face flange, wherein the first end face flange and the second end face flange are arranged on an end side of the sheet metal group in an axial direction of the sensor and are configured to rotatably support the rotor about a rotor axis of the rotor; a traction element which is guided through the sheet metal pack and which connects the first end face flange to the second end face flange in the axial direction and pretensions the first end face flange in the axial direction; and a centering element guided through the cavity, the centering element interconnecting the first end face flange and the second end face flange.

In other words, it is an aspect of the invention to provide a rotor for an electric machine, in particular for a permanently excited synchronous machine, having a sheet metal pack, wherein a first end face flange and a second end face flange are arranged on the end faces of the sheet metal pack. The rotor also comprises a traction element which is guided through the sheet metal pack and which fixes the first and second end flanges on the end sides of the sheet metal pack and axially pretensions the sheet metal pack. In this way a mounted shaft is provided.

An important aspect is therefore that the sheet metal part is prestressed in the axial direction by means of a traction element, wherein the first and second end flanges are also pressed against the sheet metal part by means of the traction element. In particular, when the rotational speed of the rotor is high, the relative movement of the individual sheet metal parts of the sheet metal part group relative to one another can be reduced by clamping the sheet metal part group in the axial direction. In this way, the torsional and/or bending stiffness of the rotor can be increased.

Furthermore, a centering element is guided through the hollow space of the sheet metal pack, which centering element connects the first end flange to the second end flange. On the one hand, the centering element can be used to axially align the first and second end face flanges with respect to each other, and on the other hand, the centering element can be used to provide a direct connection between the first and second end face flanges. Therefore, the accuracy of structural alignment of the rotor in the axial direction can be improved. Furthermore, the torsional and/or bending stiffness of the rotor can be increased.

The first end face flange and the second end face flange are configured such that they are configured for supporting the rotor in a rotatable manner about a rotor axis of the rotor. For this purpose, it is preferably provided that the first face flange and the second face flange each have a bearing journal, which is configured coaxially to the rotor axis of the rotor.

The tensioning elements for pre-tensioning the sheet metal package and for arranging the first and second end flanges on the end faces of the sheet metal package can preferably be designed as tie rods (Zuganker) and/or as tensioning screws and (Zugbolzen)/or as screw elements. Preferably, the pulling element is a screw element which is guided through the sheet metal packet and screwed into the first end face flange and/or into the second end face flange and/or is anchored back by means of a screwed nut.

The traction elements are guided through the sheet metal groups. This means that at least one bore is formed in the sheet metal part for receiving the traction element, wherein this bore is different from the cavity of the sheet metal part. In this way, the bore hole is surrounded in the circumferential direction by the sheet metal groups. In this way, increased pretensioning or uniform contact pressure can be applied in the axial direction by the traction element. Furthermore, the deformation of the first face flange and/or of the second face flange can be reduced as a result of the axial pretensioning.

The centering elements can be configured in different types. In a preferred embodiment of the invention, it is provided that the centering element is a plate group carrier on which a plate foil group is arranged. Thus, the sheet pack carrier extends through the cavity of the sheet pack. The sheet set of plates is preferably heat shrunk onto the sheet set carrier. In particular, the sheet set is placed on the sheet set carrier in the press-fit seat. Thus, on the one hand, a torque can be transmitted from the sheet metal package to the sheet metal package carrier via the press fit, and ultimately to the first end flange and/or the second end flange. On the other hand, the torque can be introduced directly from the sheet metal sheet package into the first end flange and/or the second end flange by means of the tensioning force via the tensioning element.

The sheet metal pack carrier is preferably connected to the first face flange and/or the second face flange in a form-fitting and/or material-fitting and/or force-fitting manner. In this way, a direct connection between the first end face flange and the second end face flange can be provided by the sheet metal pack carrier designed as a centering element, so that, in particular at high rotational speeds, a torque is transmitted not only by the pretensioning force but also by the centering element.

Alternatively and/or additionally, a preferred embodiment of the invention provides that the centering element is a cooling channel arranged radially at a distance from the sheet metal stack, which cooling channel is arranged coaxially to the rotor axis of the rotor, forms at least in sections a hollow shaft and connects the first end face flange to the second end face flange. In this case, a cooling channel extending through the hollow space of the sheet metal pack is formed between the first end face flange and the second end face flange, which cooling channel is connected to the first end face flange and the second end face flange in a material-locking and/or form-locking and/or force-locking manner. The cooling channel centers the two journals with respect to one another and can give the structure more rigidity and the possibility for conveying and distributing cooling liquid.

A cohesive connection is understood to mean, for example, a welded connection, in particular a laser penetration welded connection. Preferably, the form-locking connection is provided by: the contour formed at the end face of the centering element engages into a mating contour formed at the first end face flange and/or the second end face flange.

A preferred embodiment of the invention provides that the centering element has an end face driver at the respective end section which is constructed in the axial direction, and the first end face flange and/or the second end face flange have a corresponding receptacle which engages into the end face driver. In this way, the first face flange and the second face flange can be connected to one another in a material-locking manner by the centering element in a simple manner. In this way, the assembly or mounting of the rotor can be simplified.

According to an advantageous embodiment of the invention, the first end face flange has an opening which is configured coaxially to the rotor axis of the rotor and to which the cooling channel is connected. In this way, the cooling channel can be supplied with a cooling medium for cooling the rotor via the opening. By cooling the rotor, material-induced stresses of the rotor and/or of the sheet metal pack, which are caused by heating of the rotor during operation, can be reduced.

The cooling medium is preferably a cooling fluid, in particular oil.

In an advantageous embodiment of the invention, it is provided that the cooling channel has at least one radially formed escape opening. In this way, the cooling medium supplied to the cooling channel via the openings can escape through the escape openings and be sprayed on the inner side surface of the plate package carrier and/or on the inner side surface of the plate package. Preferably, the outlet opening is arranged centrally with respect to the length of the sheet metal package, so that the cooling medium can be directed against the sheet metal package at a so-called hot spot. Therefore, the cooling effect for cooling the rotor can be improved.

An advantageous embodiment of the invention provides that the first end face flange and/or the second end face flange have at least one outlet opening. In this way, the cooling medium can be discharged from the cavity via the outlet opening, and said cooling medium can reach the cavity of the sheet metal package via the cooling channel and/or the escape opening. In this case, it can preferably be provided that the outlet openings are arranged and/or formed in such a way that the cooling medium escaping from the hollow space is injected at the winding heads of the stator which circumferentially surrounds the rotor.

A preferred embodiment of the invention provides that the cooling channel has at least one radially extending support element on the outer circumferential surface, which support element is supported at least in sections on the inner side surface of the plate package carrier or on the inner side surface of the plate foil package. In this way, the torsional and/or bending stiffness of the cooling channel or of the rotor can be increased by the support element.

In an advantageous embodiment of the invention, it is provided that the first end face flange and/or the second end face flange have a centering seat which projects into the cavity and at least partially bears against the inner side surface of the sheet metal package and/or against the inner side surface of the sheet metal package carrier. In this way, a cylindrical receptacle for the sheet metal chip package is provided by the centering seat, preferably by the cylindrical seat, so that an improved axial alignment of the first end face flange, the second end face flange and the sheet metal chip package can be provided.

Furthermore, the invention relates to an electric machine for use in a vehicle, having a rotor according to the invention.

In an advantageous embodiment of the invention, it is provided that the electric machine is a permanently excited synchronous machine.

Finally, the utility model relates to a vehicle with according to the utility model discloses a motor.

Drawings

Further features and advantages of the invention emerge from the dependent claims and the following exemplary embodiments. The examples should not be construed as limiting, but rather as illustrative. The described embodiments are intended to enable those skilled in the art to practice the invention. The applicant reserves the right to claim individual or individual ones of the features disclosed in the embodiments or to add these features to the existing claims. The embodiments are explained in more detail with reference to the drawings.

Shown in these drawings are:

figure 1 longitudinal section of a rotor according to a preferred embodiment of the invention,

figure 2 is a perspective view of the rotor,

fig. 3 is a perspective view of the rotor, wherein a form-locking connection between the centering element configured as a sheet metal pack carrier and the first and second end flanges is shown,

figure 4 is a longitudinal section through a rotor with cooling channels configured as centering elements,

FIG. 5 is a perspective view of a rotor, wherein the first end face flange and the second end face flange have an escape opening,

fig. 6 a longitudinal section of the rotor, in which the centering elements are configured only as cooling channels,

FIG. 7 is a longitudinal section through the rotor, in which the cooling channels are connected in a form-locking manner to the first end-face flange and the second end-face flange,

FIG. 8 is an exploded view of the first end face flange, the second end face flange and the cooling channel,

fig. 9 is a longitudinal section through the rotor, wherein the support elements are formed on the outer lateral surface of the cooling channel.

Detailed Description

Fig. 1 shows a rotor 10 for an electric machine, in particular for a permanently excited synchronous machine. The rotor 10 comprises a cylindrically formed sheet metal disk 12, which circumferentially surrounds a cavity 14. Arranged on the end sides of the cylindrically formed sheet metal blank holder 12 are a first end flange 16 and a second end flange 18, which at least partially close off the hollow space 14 in the axial direction. The first end flange 16 and the second end flange 18 each have a bearing journal 20 for rotatably supporting the rotor 10 about a rotor axis 22 of the rotor. A pulling element 24 is guided through the first end flange 16, the group of sheet metal strips 12 and the second end flange 18, which pulling element pretensions the group of sheet metal strips 12 in the axial direction of the rotor 10. The pulling element 24 is designed as a screw element, wherein a nut 26 is screwed onto each end face of the screw element in order to fix the first end face flange 16 and the second end face flange 18 on the end face of the group of sheet metal parts 12 and to pretension the group of sheet metal parts 12 in the axial direction. By clamping and/or pre-tensioning the plate film stack 12 in the axial direction, in particular at high rotational speeds of the rotor 10, a relative movement of the individual plate films of the plate film stack 12 with respect to one another can be reduced. In this way, the torsional and bending stiffness of the rotor 10 can be increased.

In principle, only one traction element 24 can be provided. In general, as shown in the present exemplary embodiment, a plurality of traction elements 24 are arranged in the axial direction through the sheet metal packet 12, wherein the traction elements 24 are preferably arranged at regular intervals from one another in the circumferential direction.

In addition, a centering element 28 is provided, which in the present case is designed as a sheet metal pack carrier 30, wherein the sheet metal pack 12 is arranged on the sheet metal pack carrier 30. In this case, it can be provided that the sheet metal pack 12 is heat-shrunk onto the sheet metal pack carrier 30 and/or is placed onto the sheet metal pack carrier 30 in an interference fit.

In the present exemplary embodiment, the sheet metal blank holder 30 is connected to the first end flange 16 and the second end flange 18 in a form-fitting manner. In this way, the torque of the rotor can be transmitted from the plate package 12 to the plate package carrier 30 via the press-fit seats and can be transferred again by form-locking with the

respective end flanges

16, 18. On the other hand, a large part of the torque can be transmitted from the plate lamella package 12 to the

respective end flange

16, 18 via the traction element 24. In this way, a particularly rigid rotor structure can be provided, the deformation of which can be reduced, in particular at high rotor speeds.

Fig. 2 shows a perspective view of the rotor 10 shown in fig. 1. A recess 32 is arranged in the sheet metal pack 12 in the axial direction for receiving a permanent magnet 34. The recess 32 is at least partially closed in the axial direction by the first end flange 16 and the second end flange 18 resting on the end sides of the sheet metal pack 12, so that the permanent magnet 34 arranged in the recess 32 is fixed in the axial direction.

Fig. 3 shows the rotor 10 shown in fig. 2. The sheet metal pack 12 is arranged on a sheet metal pack carrier 30 designed as a centering element 28.

At the respective axially formed end section 36, the sheet metal pack carrier 30 has an end face drive 38. The end-face driver 38 is designed as a projection. The first end flange 16 and the second end flange 18 have receptacles 40, which are embodied in the present case as recesses and/or grooves, which engage in the end drivers 38. In this way, a form-fit connection between the sheet metal blank carrier 30 and the first end flange 16 or the second end flange 18 can be provided.

Fig. 4 shows the rotor 10 disclosed in fig. 1, wherein, in addition to the centering elements 28 configured as a sheet metal pack carrier 30, further centering elements 28 configured as cooling channels 42 are arranged, which connect the first end face flange 16 with the second end face flange 18. The cooling channel 42 is completely designed as a hollow shaft and is arranged coaxially to the rotor axis 22. An opening 44 is formed in the first end face flange 16, which opening extends coaxially to the rotor axis 22 of the rotor 10, wherein the cooling channel 42 is connected to the opening 44. In this way, a cooling medium 45, in particular oil, can be supplied to the cooling channel 42 through the opening 44. The cooling channel 42 has at least one radially formed outlet opening 46, through which opening 46 the cooling medium 45 can escape from the cooling channel 42. In this way, the cooling medium 45 escaping from the cooling channel 42 through the escape opening 46 can be sprayed onto the inside surface 48 of the sheet metal assembly carrier 30. The cooling medium 45 can escape from the cavity 14 of the rotor 10 through at least one outlet opening 50 formed in the first end-face flange 16 and the second end-face flange 18 and can preferably be sprayed toward the winding heads of a stator (not shown) that surrounds the rotor 10 in the circumferential direction. In this way, it is possible to cool not only the rotor 10 but also the winding heads of the stator surrounding the rotor 10.

Fig. 5 shows a perspective view of the rotor 10 shown in fig. 4. As can be seen in fig. 5, the outlet opening 50 for discharging the cooling medium 45 from the cavity 14 of the rotor 10 is formed as a material recess which extends radially inward from the outer circumference of the first end face flange 16. In this way, the outlet 50 can be produced in a simple manner and at low cost.

Fig. 6 shows a rotor 10, wherein the rotor 10 has a centering element 28 in the form of a cooling channel 42. Unlike the rotor 10 shown in fig. 4, the rotor 10 shown in fig. 6 does not include the plate pack carrier 30. In this way, the cooling medium 45 which is supplied to the cooling channel 42 by the rotor 10 via the opening 44 and which escapes from the cooling channel 42 via the escape opening 46 can be sprayed onto the inner side surface 52 of the sheet metal pack 12. The cooling channel 42 can be connected to the first face flange 16 and the second face flange 18 in a material-locking manner. The material-locking connection can be a welded connection. Particularly preferably, as shown in fig. 7, the cooling channel 42 is connected to the first end-face flange 16 and the second end-face flange 18 in a form-fitting manner. For this purpose, the centering element 28 has a face driver 38 at the respective axially formed end section 36, and the first face flange 16 and the second face flange 18 have corresponding receptacles 40 engaging in the face driver 38.

Fig. 8 shows an exploded illustration of the first end-face flange 16, the second end-face flange 18 and a centering element 28, which is arranged between the first end-face flange 16 and the second end-face flange 18 and is designed as a cooling channel 42. From this illustration, a form-locking connection between the centering element 28 and the

respective end flange

16, 18 can be seen. In this case, a face driver 38 formed on the end face of the centering element 28 engages in a corresponding receptacle 40 of the first face flange 16 or of the second face flange 18.

Fig. 9 shows a rotor 10, in which the centering element 28 is designed as a cooling channel 42, the cooling channel 42 having a hollow shaft only in sections. Radially extending support elements 56 are formed on the outer circumferential surface 54 of the cooling channel 42, which support elements bear against the inner side surface 52 of the sheet metal pack 12. In this way, the rigidity of the cooling passage 42 can be increased.

List of reference numerals

10 rotor

12 sheet material slice group

14 cavity

16 first end flange

18 second end face flange

20 bearing neck

22 rotor axis

24 traction element

26 nut

28 centering element

30 plate group carrier

32 recess

34 permanent magnet

36 end section

38 end surface driving part

40 receiving part

42 cooling channel

44 opening

45 cooling medium

46 escape opening

48 inside surface of plate group carrier

50 discharge port

Inside surface of 52 sheet groups

54 circumferential surface of cooling channel

56 support element

Claims

1. Rotor (10) for an electrical machine, having:

a group of sheet metal layers (12) surrounding a cavity (14),

a first end face flange (16) and a second end face flange (18), wherein,

the first end-face flange (16) and the second end-face flange (18) are arranged on the end sides of the sheet metal pack (12) in the axial direction of the rotor (10) and are designed to rotatably support the rotor (10) about a rotor axis (22) of the rotor,

a pulling element (24) which is guided through the sheet metal pack (12) and which axially connects and pretensions the first end flange (16) and the second end flange (18), and

a centering element (28) guided through the cavity (14), the centering element interconnecting the first end face flange (16) and the second end face flange (18).

2. Rotor according to claim 1, characterized in that the centering element (28) is a plate pack carrier (30) on which the plate pack (12) is arranged.

3. The rotor according to any one of claims 1 or 2, characterized in that the centering element (28) is a cooling channel (42) arranged radially spaced apart from the sheet-material group (12), which is arranged coaxially to a rotor axis (22) of the rotor (10), at least in sections constitutes a hollow shaft and connects the first end-face flange (16) with the second end-face flange (18).

4. The rotor as recited in claim 1, characterized in that the centering element (28) has a face driver (38) at the respective axially configured end section (36), and the first face flange (16) and/or the second face flange (18) has a corresponding receptacle (40) engaging into the face driver (36).

5. The rotor as recited in claim 1, characterized in that the first end face flange (16) has an opening (44) which is configured coaxially to a rotor axis (22) of the rotor (10), and the cooling channel (42) is connected to this opening (44).

6. The rotor as recited in claim 3, characterized in that the cooling channel (42) has at least one radially configured escape opening (46).

7. The rotor as recited in claim 1, characterized in that the first end face flange (16) and/or the second end face flange (18) has at least one discharge opening (50).

8. The rotor as recited in claim 3, characterized in that the cooling channel (42) has at least one radially extending support element (56) on an outer circumferential surface (54), which support element is supported at least in sections on an inner side surface (48) of the sheet material group carrier (30) or on an inner side surface (52) of the sheet material group (12).

9. The rotor as recited in claim 1, characterized in that the first end face flange (16) and/or the second end face flange (18) has a centering flange which projects into the cavity (14) and which bears at least in sections against an inner side surface (52) of the sheet metal pack (12) and/or against an inner side surface (48) of the sheet metal pack carrier (30).

10. Electric machine for use in a vehicle, having a rotor (10) according to any one of the preceding claims.

11. The machine of claim 10, wherein the machine is a permanently excited synchronous machine.

12. Vehicle with an electric machine according to any of claims 10 or 11.