DE102017220422A1 - Rotor for an electric machine - Google Patents

Abstract

The invention relates to a rotor (10) for arrangement in an electric machine (11), with a hollow cylinder-shaped laminated core carrier (12) on whose outer peripheral surface (16) a rotor lamination stack (14) can be arranged, and to the respective axial end of the lamination stack carrier (12) an end flange (18) is arranged, wherein the respective end flange (18) has a shaft journal (20), and in the hollow cylinder-shaped laminated core (12) a vibration damper (24) is arranged and / or formed.

Description

The invention relates to a rotor for arrangement in an electric machine, wherein the rotor has an integrated vibration damper. The invention also relates to an electric machine with the rotor according to the invention, as well as a motor vehicle with the electric machine according to the invention.

Electric machines with a rotor are well known. The known electrical machines generally have a stator and a rotatable in the stator about a rotor axis rotatable rotor.

Furthermore, it is known that continuously bending vibrations can occur during operation in the rotor shaft of the rotor. Causes can be mainly major changes in shaft speed during acceleration and braking. Likewise, however, an imbalance of the rotor can trigger bending vibrations. Therefore, rotors with a vibration damper are also known in order to avoid or reduce dangerous torsional vibrations in the rotatable shaft of the electric machine during a start-up operation, a deployment operation or during normal operation of the electrical machine.

From the US 2010/0225121 Al, for example, a rotating electric machine is known in which a torsional vibration damper is integrated into the rotating electrical machine. The electric machine has a rotor core with a first end and a second end. The integrated torsional vibration damper consists of a torsionally flexible coupling and a torsion damper and provides a mechanical damping. The integrated torsional vibration damper is attached to the rotary shaft of the electric machine by a flange. The rotor lamination stack is attached to the first end to the integrated torsional vibration damper by suitable structural members, such as a mounting flange, and is not fixedly attached directly to the rotatable shaft.

A disadvantage of the known rotor or the known electric machine is the increased space requirement in the axial direction, since the torsional vibration damper is flanged in the axial direction on the rotor core and thus requires a correspondingly large space in the longitudinal direction of the electric machine.

It is the object of the present invention to provide a rotor for an electric machine with increased running characteristics, which has a reduced space requirement.

The object is solved by the subject matter of the independent patent claim. Advantageous embodiments of the invention are set forth in the dependent claims, the description and the drawings, wherein each feature, both individually and in combination, may constitute an aspect of the invention.

According to the invention, a rotor is provided for arrangement in an electric machine, with a hollow cylinder-shaped laminated core, on the outer peripheral surface of a rotor laminated core can be arranged, and at the respective axial end of the laminated core carrier an end flange is arranged, wherein the respective end flange has a shaft journal, and in a vibration damper is arranged and / or formed the hollow cylindrical shaped laminated core carrier.

In other words, it is an aspect of the invention to provide a rotor for an electric machine having a hollow cylindrical shaped laminated core. This can be, for example, a hollow rotor shaft. At least one rotor core can be arranged and / or arranged on the laminated core carrier. Thus, the rotor laminated core can preferably be arranged rotationally fixed on the laminated core and transmit a torque to the laminated core. At the respective axial ends of the laminated core carrier an end flange is arranged, wherein each end flange has a shaft journal, which is generally formed coaxially to the rotor axis of rotation.

Within the hollow cylinder-shaped laminated core carrier, or the hollow rotor shaft of the vibration absorber is arranged. The vibration damper acts directly on the rotor or on the hollow rotor shaft, so that the vibration damper can reduce unwanted vibrations and / or noises at the place of formation and thus positively influence the running properties of the rotor. The vibrations of the rotor causing the noise can be transmitted to the vibration absorber. The design of the vibration absorber is preferably tuned to the frequencies that may occur during operation of the rotor. These can preferably be determined in advance by simulations and / or tests. In this way, a rotor is provided with an integrated vibration absorber, which can have a reduced space and increased operating characteristics. In addition to the space-saving design, the manufacturing costs can also be reduced. In addition, the life and / or reliability of the rotor or the electric machine can be increased.

Under a vibration damper is a vibratory mass-spring damping Understand system that basically can be designed differently. An advantageous development of the invention provides that the vibration damper comprises a rubber-elastic element with at least one arranged in the rubber-elastic element and / or embedded Tilgermasse. The rubber-elastic element is preferably an elastomer, in particular a silicone elastomer, and most preferably a vulcanized silicone elastomer. Silicone elastomers are suitable and designed to convert vibration energy into heat. The absorber mass can be designed as desired. As a rule, the absorber mass has a higher density than the rubber-elastic element. Preferably, the absorber mass is formed as a metal core, but this is not limited exclusively to a metal core. The advantage of a metal core is that it is easy and inexpensive to produce.

In an advantageous development of the invention, it is provided that the absorber mass is held within the elastomeric element in the axial direction of the rotor and in the radial direction of the rotor, wherein the elastomeric element can swing at least partially in the radial direction as a result of rotation of the rotor about its axis of rotation , and the absorber mass vibrates in the radial direction. This means that the absorber mass is positioned in the radial direction and in the axial direction within the rubber-elastic element. The absorber mass acts within the rubber-elastic element as a vibrating mass and the rubber-elastic element takes over the function of the spring and the damper. Unwanted vibrations of the rotor as a result of its rotation stimulate the absorber mass to oscillate in the radial direction. In which the damping mass withdraws energy from the stimulating vibration, the vibration is dampened.

The absorber mass can be connected in different ways with the rubber-elastic element. A preferred embodiment of the invention provides that the absorber mass is arranged cohesively and / or positively in the rubber-elastic element. For example, the damping mass and the rubber-elastic element can be vulcanized together, pressed together and / or glued together. In this way, the absorber mass can be positioned in the rubber-elastic element.

In an advantageous development of the invention it is provided that the absorber mass is arranged centrally in the longitudinal direction of the laminated core, this does not mean that the absorber mass is located on the rotor axis of rotation. Rather, the absorber mass is arranged in the radial direction at a distance from the rotor axis of rotation.

A preferred embodiment of the invention is that the vibration damper in a longitudinal section through the rotor has a rectilinear configuration. In this way, the vibration absorber is preferably arranged coaxially in the laminated core and is clamped between the end flanges. In the radial direction, the vibration damper over its entire length at a distance from the inner circumferential surface of the laminated core, so that the absorber mass can oscillate in the radial direction.

Alternatively, a preferred embodiment of the invention provides that the vibration damper in a longitudinal section through the rotor has a dumbbell-shaped configuration. Accordingly, the vibration absorber between the respective end portions on a central portion which comprises a reduced outer diameter relative to the respective end portions. The end portions of the vibration absorber are based at least in sections against the inner circumferential surface of the laminated core carrier, whereby the vibration damper is positionally positionable in the laminated core carrier. The middle portion is formed so that it can swing in the radial direction. Accordingly, the absorber mass is arranged in the middle section.

An advantageous development of the invention provides that the vibration absorber is arranged cohesively and / or positively in the laminated core and / or is connected to an inner circumferential surface of the laminated core carrier. A cohesive connection is preferably an adhesive connection. Under a positive connection is to be understood that the rubber-elastic element is clamped to the laminated core and / or the end flanges and thus fixed in position.

According to a preferred embodiment of the invention, it is provided that the end flanges and the shaft journal have a coaxial first bore, and the vibration damper has a coaxial second bore, and the first bore and the second bore are interconnected such that a continuous cooling channel is formed. Accordingly, a cooling passage, through which a cooling medium can be transported, passes through the rotor. The cooling channel is formed continuously. This means that the formed in the vibration absorber second hole connects to the formed in the end flanges and the shaft journal first holes. An essential point is that the vibration damper itself forms a part of the cooling channel, ie the peripheral surface of the cooling channel. In this way, a rotor is provided which is easily coolable, can have improved running properties, a reduced installation space and a reduced weight.

A cooling medium is preferably understood to mean a cooling liquid. The cooling liquid is particularly preferably an oil. In this context, an advantageous development of the invention is that the respective shaft journal has at least one radial bore, which is guided to the axial first bore. Thus, a cooling medium can escape from the cooling channel via the radial bore and preferably be sprayed against winding heads of a stator surrounding the rotor. Thus, the winding heads of the stator can be easily cooled by the cooling medium supplied to the rotor and exiting through the radial bores.

The invention also relates to an electric machine with the rotor according to the invention, wherein the rotor is at least partially surrounded by a stator.

Finally, the invention relates to a motor vehicle with the electric machine according to the invention.

Further features and advantages of the present invention will become apparent from the dependent claims and the following embodiments. The embodiments are not limiting, but rather to be understood as exemplary, they should enable the skilled person to carry out the invention. The Applicant reserves the right to make individual or several of the features disclosed in the exemplary embodiments the subject matter of patent claims or to include such features in existing claims. The embodiments are explained in more detail with reference to drawings.

• 1 einen Längsschnitt durch einen Rotor mit einem integrierten Schwingungstilger gemäß einem ersten Ausführungsbeispiel der Erfindung,
• 2 einen Längsschnitt durch den Rotor mit dem integrierten Schwingungstilger gemäß dem ersten Ausführungsbeispiel, wobei der Schwingungstilger in radialer Richtung innen positioniert ist,
• 3 einen Längsschnitt durch den Rotor mit dem integrierten Schwingungstilger gemäß einem zweiten Ausführungsbeispiel der Erfindung,
• 4 eine elektrische Maschine mit dem Rotor gemäß dem zweiten Ausführungsbeispiel der Erfindung.

In these show:

• 1 a longitudinal section through a rotor with an integrated vibration absorber according to a first embodiment of the invention,
• 2 a longitudinal section through the rotor with the integrated vibration absorber according to the first embodiment, wherein the vibration damper is positioned in the radial direction inside,
• 3 a longitudinal section through the rotor with the integrated vibration absorber according to a second embodiment of the invention,
• 4 an electric machine with the rotor according to the second embodiment of the invention.

In 1 is a rotor 10 for an electric machine 11 shown. The rotor 10 has a hollow cylindrical shaped laminated core 12 on. The laminated box carrier 12 may be, for example, a hollow rotor shaft. The laminated box carrier 12 preferably has an inner diameter of> 30 mm. On the laminated box carrier 12 is a rotor core 14 arranged. The rotor core 14 is preferably rotationally fixed on the laminated core 12 attached. This means that the rotor core 14 at least in sections on an outer peripheral surface 16 of the laminated core carrier 12 is present and / or connected to this preferably frictionally and / or cohesively. Thus, a rotational movement and / or a torque of the rotor core can 14 on the laminated core 12 be transmitted.

At the respective axial ends of the laminated core carrier 12 is a front flange 18 arranged, with each end flange 18 a shaft journal 20 having, coaxial with the rotor axis of rotation 22 is trained. Within the hollow cylindrical shaped laminated core carrier 12 or the hollow rotor shaft is the vibration damper 24 arranged.

In this way, a rotor 10 with an integrated vibration damper 24 provided, which may have a reduced space and increased operating characteristics. In addition to the space-saving design of the rotor 10 with the integrated vibration damper 24 In addition, the production costs can be reduced.

The vibration absorber 24 is a vibratory mass-spring damping system. It is provided that the vibration damper 24 a rubber-elastic element 26 with at least one in the rubber-elastic element 26 arranged and / or embedded Tilgermasse 28 includes. The rubber-elastic element 26 is a silicone elastomer. Silicone elastomers are suitable and designed to convert vibration energy into heat. The absorber mass 28 is formed in the present embodiment as a metal core. The advantage of a metal core is that it is simple and inexpensive to produce and has a higher density compared to the silicone elastomer.

The absorber mass 28 is inside the rubber elastic element 26 in the axial direction of the rotor 10 and in the radial direction of the rotor 10 held, with the rubber-elastic element 26 in consequence of a rotation of the rotor 10 around its rotor axis of rotation 22 at least partially swing in the radial direction, and the absorber mass 28 vibrates in the radial direction. This means that the absorber mass 28 within the laminated core carrier 12 in the radial direction and in the axial direction within the rubber-elastic element 26 is positioned. The absorber mass 28 acts within the rubber-elastic element 26 as a vibrating mass and the rubber-elastic element 26 takes over the function of the spring and the damper. unwanted Vibrations of the rotor 10 as a result of this rotation, the absorber mass is raining 28 to vibrations in the radial direction. In which the absorber mass 28 the exciting vibration withdraws energy, the vibration is damped.

The absorber mass 28 is in the longitudinal direction of the laminated core carrier 12 centered, this does not mean that the absorber mass 28 on the rotor axis of rotation 22 lies. Rather, the absorber mass 28 spaced in the radial direction to the rotor axis of rotation 22 arranged. In the present embodiment, the absorber mass 28 arranged radially on the outside.

The absorber mass 28 is with the rubber-elastic element 26 glued so that these firmly or captive with the rubber-elastic element 26 connected is.

According to the first embodiment it is provided that the vibration damper 24 in longitudinal section through the rotor 10 has a straight course. This is the vibration absorber 24 coaxial in the laminated core 12 arranged and between the end flanges 18 clamped. In the radial direction, the vibration absorber 24 over its entire length a distance to the inner lateral surface 30 of the laminated core carrier 12 on, leaving the absorber mass 28 can swing in the radial direction. The outer diameter of the vibration absorber 24 in the area of the absorber mass 28 is at least 5 mm smaller than the inner diameter of the laminated core 12 ,

The 2 shows that off 1 known rotor 10 according to the first embodiment, in contrast to 1 the absorber mass 28 is offset in the radial direction inwards. In this way, the natural frequency of the vibration absorber 24 be adjusted. Moreover, by the weight and / or the size of the absorber mass 28 the natural frequency of the vibration absorber 24 varied and fixed.

Furthermore, it can be seen that the end flanges 18 and the shaft journals 20 a coaxial first hole 32 respectively. The vibration absorber 24 has a coaxial second bore 34 on, with the first hole 32 and the second hole 34 are connected to each other such that a continuous cooling channel 36 is trained. Part of the cooling channel 36 is thus due to the vibration damper 24 educated. The cooling channel 36 is set up by the cooling channel 36 a cooling medium 38 , preferably an oil, for cooling the rotor 10 can be passed. Thus, a rotor 10 provided, which is easily coolable, can have improved runnability and a reduced installation space.

The respective shaft journal 20 has at least one radial bore 40 up to the axial first bore 32 is guided. Thus, the cooling medium 38 from the cooling channel 36 over the radial bore 40 emerge and preferably against winding heads 42 one the rotor 10 surrounding stator 44 be sprayed. Thus, the windings can 42 of the stator 44 through that the rotor 10 supplied cooling medium 38 be cooled in a simple manner.

In 3 is the rotor 10 with the integrated vibration damper 24 according to a second preferred embodiment. In contrast to the first embodiment, as in the 1 and 2 is shown, the vibration absorber 24 in the second embodiment in a longitudinal section through the rotor 10 no rectilinear design but a dumbbell-shaped configuration. Thus, the vibration absorber 24 between the respective end sections 46 a middle section 48 with one opposite the respective end sections 46 reduced outside diameter. The end sections 46 the vibration absorber 24 are supported at least in sections against the inner surface 30 of the laminated core carrier 12 down, causing the vibration absorber 24 secure in the sheet metal carrier 12 is positionable. The middle section 48 is designed such that it can oscillate in the radial direction. Accordingly, the absorber mass 28 arranged in the middle section. Furthermore, it can be seen that the absorber mass 28 in the radial direction in the middle of the rubber-elastic element 26 is arranged. The outer diameter of the vibration absorber 24 in the middle section is at least 5 mm smaller than the inner diameter of the laminated core carrier 12 ,

The 4 shows an electric machine 11 with the rotor 10 and the integrated vibration absorber 24 according to the second embodiment. The rotor 10 is inside a housing 50 around the rotor axis of rotation 22 rotatably mounted, wherein the rotor 10 in the circumferential direction of the stator 44 is surrounded. A shaft journal 20 of the rotor 10 is with a transmission input shaft 52 a gearbox 54 coupled, so that a rotational movement of the rotor via the transmission input shaft 52 on the gearbox 54 is transferable.

The cooling medium 38 passing through the coaxial cooling channel 36 is transported over the radial bores 40 in the shaft journal 20 in consequence of a rotation of the rotor 10 injected in the radial direction to the outside and against the winding heads 42 of the stator 44 sprayed to the windings 42 to cool. About in the laminated core 12 arranged vibration absorber 24 can flexural vibrations of the rotor 10 be effectively reduced, reducing the running characteristics of the electrical Machine can be increased. By the arrangement of the vibration absorber 24 in the hollow cylindrical shaped laminated core 12 can the space of the electric machine 11 be reduced.

LIST OF REFERENCE NUMBERS

10

rotor

11

Electric machine

12

Laminated core carrier

14

Laminated core

16

Outer peripheral surface laminated core carrier

18

end flange

20

shaft journal

22

Rotor axis of rotation

24

vibration absorber

26

Rubber-elastic element

28

absorber mass

30

Inner lateral surface of laminated core carrier

32

First drilling

34

Second hole

36

cooling channel

38

cooling medium

40

Radial bore

42

winding heads

44

stator

46

end

48

Middle section

50

casing

52

Transmission input shaft

54

transmission

QUOTES INCLUDE IN THE DESCRIPTION

This list of the documents listed by the applicant has been 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.

Cited patent literature

• US 2010/0225121 [0004]

Claims (11)

Rotor (10) for arrangement in an electric machine (11), with a hollow cylindrical shaped laminated core (12), on whose outer peripheral surface (16) a rotor core (14) can be arranged, and at the respective axial end of the laminated core (12) End flange (18) is arranged, wherein the respective end flange (18) has a shaft journal (20), and in the hollow cylindrical shaped laminated core (12) a vibration damper (24) is arranged and / or formed. Rotor after Claim 1 , characterized in that the vibration damper (24) comprises a rubber-elastic element (26) with at least one in the rubber-elastic element (26) arranged and / or embedded Tilgermasse (28). Rotor after Claim 2 , characterized in that the absorber mass (28) within the elastomeric element (26) in the axial direction of the rotor (10) and in the radial direction of the rotor (10) is held, wherein the rubber-elastic element (26) as a result of rotation of the rotor (10) about the rotor rotational axis (22) at least partially swing in the radial direction, and the absorber mass (28) oscillates in the radial direction. Rotor after Claim 2 or 3 , characterized in that the absorber mass (28) is arranged cohesively and / or positively in the rubber-elastic element (26). Rotor after one of Claims 1 to 4 , characterized in that the vibration damper (24) in a longitudinal section through the rotor (10) has a rectilinear configuration. Rotor after one of Claims 1 to 4 , characterized in that the vibration damper (24) in a longitudinal section through the rotor (10) has a dumbbell-shaped configuration. Rotor according to one of the preceding claims, characterized in that the vibration damper (24) is arranged cohesively and / or positively in the laminated core (12) and / or with an inner circumferential surface (30) of the laminated core (12) is connected. Rotor according to one of the preceding claims, characterized in that the end flanges (18) and the shaft journals (20) have a coaxial first bore (32) and the vibration absorber (24) has a coaxial second bore (34), and the first bore ( 32) and the second bore (34) are interconnected such that a continuous cooling channel (36) is formed. Rotor after Claim 8 , characterized in that the respective shaft journal (20) has at least one radial bore (40) which is guided to the axial first bore (32). Electric machine (11) with a rotor (10) according to one of the preceding claims. Motor vehicle with an electric machine (11) according to Claim 10 ,

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