Motor

Abstract

The invention relates to an electric machine (1), in particular for a motor vehicle, comprising: a plurality of phases; a plurality of coupling sections (4 to 6) connected to each phase for contacting the electric machine (1) with a control device, in particular an inverter; and a star-shaped conductor (7), the star-shaped conductor (7) and the coupling parts (4 to 6) being arranged at different circumferential positions (8, 9) with respect to the longitudinal axis (2) of the electric machine (1).

Description

Field of the Invention

[0001] The invention relates to an electric machine, in particular an electric machine for a motor vehicle, which electric machine comprises: a plurality of phases; a plurality of phase connections connected to the respective phases for contacting the electric machine with a control device, in particular an inverter; and a star conductor (Sternleiter). Background Art

[0002] In the prior art, electric machines are basically known which are used, for example, as drive units in motor vehicles and have a plurality of phases and a plurality of phase connections connected to the respective phases for contacting the electric machine with a control device. Current can be introduced into the electric machine from the control device, such as an inverter, via the phase connections.

[0003] Due to the continuously increasing requirements for power density and the optimized use of the available installation space, the phase connections can be arranged outside the stator space of the electric machine. Here, when the electric machine is connected in star connection, the star conductor is usually installed in a module having the described phase connections and arranged in the installation space. Then such a connection module is arranged at a suitable location in the installation space, for example, in the transmission of a motor vehicle or in another installation space. However, this means that the entire connection module requires a certain continuously occupied installation space. Summary of the Invention

[0004] It is an object of the present invention to provide an electric machine which is improved compared to the prior art and which offers greater flexibility, in particular with regard to the use of installation space.

[0005] This object is achieved by an electric machine having the features of claim 1. Advantageous designs are the subject matter of the dependent claims.

[0006] As described, the invention relates to an electric machine, in particular an electric machine for a motor vehicle, which is designed, for example, as a drive unit or a traction drive for a motor vehicle, in particular as an electric axle drive. The electric machine has: a plurality of phases, for example three phases u, v, w; and a plurality of phase connections for contacting the respective phases, that is, for connecting the respective phases to a control device, in particular an inverter, in order to supply electrical energy to the electric machine. Here, a star connection is provided for the electric machine, so that a star conductor is formed at the star point (Sternpunkt) of the connection. The invention is based on the recognition that the star conductor and the phase connections are arranged at different circumferential positions relative to the longitudinal axis of the electric machine.

[0007] Therefore, different from the above-mentioned prior art, the star conductor and the phase connection part can be arranged independently of each other in the structural space. As described above, the phase connection part can form a module, for example, and the phase connection part is arranged in the module and is, for example, fixedly positioned relative to each other in a defined relative position. The star conductor can be arranged independently of the phase connection part at different positions, so that the star conductor and the phase connection part together must occupy less continuous structural space, and they can be arranged more flexibly and independently of each other.

[0008] In other words, a continuous section of the structural space may only be sufficient to accommodate the phase connection part or the star conductor, so that the phase connection part and the star conductor can be arranged at different circumferential positions, that is, arranged in different sections of the structural space, and here, for example, in the radial direction, compared with the star conductor and the phase connection part being combined in a module and fixedly positioned relative to each other, less overall structural space must be occupied. Thereby, higher flexibility can be achieved when using the available structural space. The longitudinal axis of the electric machine can in particular be the symmetry axis of the electric machine, especially the rotation axis of the rotor. Here, the longitudinal axis extends axially through the stator space or the rotor space. The star conductor can also be referred to as the "neutral conductor".

[0009] According to another design of the electric machine, the star conductor and the phase connection part can be arranged, in particular, at the same radial position or different radial positions relative to the rotation axis of the electric machine. As explained, in the proposed electric machine, in principle, independent positioning of the star conductor and the phase connection part in the electric machine can be achieved. According to the described design, on the one hand, it can be stipulated that the phase connection part and the star conductor are arranged at different circumferential positions and the same radial position, or arranged at different circumferential positions and different radial positions.

[0010] Here, the circumferential position is understood as the position of the star conductor or the phase connection part in the rotational direction around the longitudinal axis of the electric machine, such as the rotation axis of the electric machine. The radial position is particularly understood as the distance from the rotation axis. By arranging the star conductor and the phase connection part at different circumferential positions and optionally at the same radial position or different radial positions, high flexibility is provided for arranging the components of the electric machine, so that the available structural space can be utilized particularly flexibly.

[0011] In an improved design of the electric machine, a protective cover may be provided, which at least partially surrounds the star conductor. The protective cover may be made of plastic, for example. On the one hand, the protective cover can support the positioning of the star conductor of the electric machine, and on the other hand, it causes or additionally supports the isolation of the star conductor from other components of the electric machine. The star conductor is particularly understood as a connecting section, that is, an extended conductive section of the star point, where the individual phases are connected to each other. The protective cover at least partially, particularly completely, surrounds the star conductor, so that the star conductor is protected by the protective cover from external influences or other conductive elements. Thus, the star conductor is surrounded by the protective cover in such a way that the star conductor cannot reach other conductive elements of the electric machine, but is protected by the protective cover from these elements.

[0012] As described above, the protective cover can also contribute to or cause the positioning of the star conductor. According to the design, the protective cover can be designed to support the star conductor in a defined position in the housing of the electric machine. Here, for example, it can be stipulated that the protective cover does not fixedly connect the star conductor to the housing, but causes a "floating" support, where the protective cover defines the position of the star conductor, but allows slight movement. This can in particular achieve vibration decoupling of the star conductor from the housing, so that vibrations of the housing can be attenuated by the protective cover. In other words, the housing can vibrate relative to the protective cover, but the vibrations are not directly transmitted to the star conductor through the protective cover, but are attenuated if necessary. In addition, as described, the protective cover causes as much electrical isolation as possible of the star conductor within the housing. In addition, by supporting the star conductor in a defined position, the maintenance of the electrical clearance and creepage distance is ensured.

[0013] According to another design of the electric machine, the protective cover may have an axial stop, which prevents accidental loosening of the protective cover. The axial direction of the star conductor or the protective cover is understood as the direction in which the protective cover is inserted or placed on the star conductor. The axial direction can also be understood as the direction predetermined by one or more free ends of the star conductor, or the direction in which the free ends of the conductors of the star conductor point, and these conductors are connected to each other through the star conductor. The axial stop can be, for example, a bulge at the protective cover. The axial stop can prevent the protective cover from accidentally loosening from the star conductor within the available structural space. In other words, the axial stop is selected such that there is a defined gap between the axial stop and the inner wall of the housing of the electric machine, however, this gap is maintained in the assembled state, so that even during the loosening movement of the protective cover from the star conductor, the available gap is not sufficient to loosen the protective cover. The axial stop creates a defined electrical clearance and / or creepage distance within the housing, which contributes to the isolation of the star conductor.

[0014] The electric machine can also be improved in such a way that the protective cover has at least one locking part, in particular two opposing locking hooks, which are designed to lock the protective cover at the star conductor. The locking hooks or locking parts can also be referred to as or regarded as clamping hooks or clips. In the installed state of the star conductor, two locking parts can be provided in the circumferential direction of the star conductor and on opposing sides. The protective cover can in particular be plugged onto the star conductor from the direction of the free ends of the conductors connected by the star conductor. Here, the star conductor forms a corresponding locking surface for each locking part, and the locking part can be latched or locked at this locking surface. The locking part prevents the unintentional loosening of the protective cover. In particular, in combination with the above-mentioned axial stop, it is ensured that even if the locking part is damaged, for example due to the aging of the locking part during the service life of the electric machine, the protective cover cannot be unintentionally loosened.

[0015] The protective cover can also have at least one spacing part, which is designed to position the star conductor in the radial direction. The spacing part can be a wing protruding from the outer surface of the protective cover, which contacts the inner surface of the housing of the electric machine. In particular, two spacing parts opposing each other in the radial direction of the electric machine can be provided, such that the star conductor is positioned in a defined manner in the radial direction by the protective cover. The spacing part maintains a defined distance of the protective cover in the housing in the radial direction, such that the star conductor protected by the protective cover is also positioned in a defined manner in the housing of the electric machine. It can be specifically provided that the spacing part can be elastically deformed in a defined manner, such that vibration decoupling from the housing of the electric machine can also be achieved through the spacing part. In addition, the spacing part can be designed to attenuate the occurring vibrations, in particular due to its elastic embodiment or its deformability.

[0016] In addition to the electric machine, the invention also relates to an electric vehicle axle drive, which is particularly used in motor vehicles and includes an inverter and the above-mentioned electric machine. Here, the inverter and the electric machine can form an electrical component for the electric vehicle axle drive. The inverter and the electric machine can be connected to each other through a phase connection part or a power connection part. In addition, the invention relates to a motor vehicle, which includes the above-mentioned electric machine and / or the above-mentioned electric vehicle axle drive. In addition, the invention relates to a manufacturing method of an electric machine, in particular an electric machine for motor vehicles, which includes: a plurality of phases; a plurality of phase connection parts connected to the respective phases for the contact of the electric machine with a control device, in particular an inverter; and a star conductor, wherein the star conductor and the phase connection parts are arranged at different circumferential positions relative to the longitudinal axis of the electric machine.

[0017] All the advantages, details and features described with respect to the electric machine can be fully transferred to the electric vehicle axle drive, the motor vehicle and the method. Description of the Drawings

[0018] The present invention will be described below with reference to the accompanying drawings by way of examples. The drawings are schematic illustrations, in which:

[0019] Figure 1 A schematic section of the electric machine is shown in a view looking radially;

[0020] Figure 2 is shown schematically in a three - dimensional view Figure 1 of a section of the electric machine;

[0021] Figure 3 is shown schematically in a view looking axially Figure 1 、 Figure 2 of a section of the electric machine;

[0022] Figure 4 shows Figures 1 to 3 a schematic section of the star conductor of the electric machine; and

[0023] Figure 5 shows Figures 1 to 4 a schematic sectional view of the electric machine. DETAILED DESCRIPTION

[0024] Figure 1 A principle illustration of the electric machine 1 is shown in a view looking in the radial direction, i.e., from the outside towards the longitudinal axis 2 (e.g., the axis of rotation of the rotor of the electric machine 1). It can be seen that the electric machine 1 has a plurality of conductors that are guided through the stator 3 of the electric machine 1, which can be referred to or regarded as "hairpins" or can be implemented as such "hairpins". Each conductor is assigned to each phase, in this embodiment to three phases, and they lead out from the stator 3 at the phase connections 4 to 6. The phase connections 4 to 6 can be connected, for example, to a control device, in particular an inverter, not further shown.

[0025] Furthermore, in Figure 1 a star conductor 7 is shown, which forms the star point of the star connection of the electric machine 1. As can be learned from Figures 1 to 3 the phase connections 4 to 6 and the star conductor 7 are arranged at different circumferential positions 8, 9. Here, the phase connections 4 to 6 can be combined to form a module 10, i.e., they are arranged relative to each other, for example, in a defined relative position. The module 10 can be connected to the control device, for example, so that the phase connections 4 to 6 are in contact with the control device.

[0026] By arranging the star conductor 7 and the phase connections 4 to 6 independently in the circumferential direction, the use of the available structural space has a high degree of flexibility. In contrast, a conventionally formed module 10 formed by the phase connections 4 to 6 and the star conductor 7 requires significantly more continuous structural space, especially because a defined creepage distance and electrical clearance must always be maintained between the star conductor 7 and the phase connections 4 to 6. By arranging the star conductor 7 at a circumferential position 8 different from the circumferential position 9 at which the phase connections 4 to 6 are arranged, on the one hand, structural space in the radial direction is saved, and on the other hand, at the same time, the star conductor 7 is spaced apart from the phase connections 4 to 6, so that a defined creepage distance and electrical clearance are maintained.

[0027] As can also be learned fromFigures 1 to 3 It is known that the star conductor 7 and the phase connection parts 4 to 6 are arranged at the same radial position 11, that is, the star conductor 7 and the phase connection parts 4 to 6 are at the same distance from the longitudinal axis 2 in the radial direction. Alternatively, the star conductor 7 and the phase connection parts 4 to 6 can also be arranged at different radial positions 11 accordingly. Thus, the star conductor 7 and the phase connection parts 4 to 6 can be arranged at different circumferential positions 8, 9 on the one hand and at the same or different radial positions 11 at the same time.

[0028] As can also be seen from the drawings, the star conductor 7 has a protective cover 12 which at least partially surrounds the star conductor 7. In the illustrated embodiment, the protective cover 12 prevents the star conductor 7 from coming into contact with other components of the electric machine 1. In particular, as will be explained below, the protective cover 12 positions the star conductor 7 and isolates the star conductor 7 from its surroundings. Preferably, in Figure 4 、 Figure 5 it is shown that the protective cover 12 is "inserted" onto the star conductor 7 in the direction towards the free end of the star conductor 7. For this purpose, the protective cover 12 is provided with a locking part 13, in particular a locking hook, which locks at the locking surface 14 of the star conductor 7. This prevents the protective cover 12 from accidentally coming loose from the star conductor 7.

[0029] In addition, the protective cover 12 has an axial stop 15 which also prevents the protective cover 12 from accidentally coming loose from the star conductor 7. In particular, in Figure 5 it is shown that in the assembled state, a gap 17 is formed between the inner surface 16 of the housing of the electric machine 1 and the axial stop 15. The axial stop 15 and the gap 17 are selected such that a defined electrical clearance and creepage distance are maintained, yet accidental loosening of the protective cover 12 is prevented, since for example when the locking part 13 fails, the gap 17 is not sufficient to separate the protective cover 12 from the star conductor 7 to such an extent that the protective cover 12 can become loose.

[0030] As mentioned at the beginning, in addition to isolating the star conductor 7, the protective cover 12 is designed to position the star conductor 7. For this purpose, in the illustrated embodiment, the protective cover 12 has a spacer 18 which projects from the outer surface 19 of the protective cover 12. The spacer 18 can be understood as a "wing" which extends away from the base body of the protective cover 12. By means of the spacer 18, the protective cover 12 and thus the star conductor 7 are supported "floating" relative to the inner surface 16 in particular in the housing of the electric machine 1. In other words, a defined movement of the star conductor 7 in the housing of the electric machine 1 can be achieved. Thereby, vibration decoupling of the star conductor 7 is achieved, so that direct vibration transmission from the housing of the electric machine 1 to the star conductor 7 is decoupled.

[0031] The advantages, details, and features shown in the various embodiments can be combined with one another arbitrarily, can be interchanged, and can be transferred to one another. The electric machine 1 can in particular also be part of an electric drive axle or an electric vehicle axle drive that can be arranged in a motor vehicle. Thus, such a motor vehicle can have an electric drive axle that has the electric machine 1 as a drive device.

[0032] List of reference numerals

[0033] 1 Electric machine

[0034] 2 Longitudinal axis

[0035] 3 Stator

[0036] 4 to 6-phase connection

[0037] 7 Star conductor

[0038] 8, 9 Circumferential positions

[0039] 10 Module

[0040] 11 Radial position

[0041] 12 Protective cover

[0042] 13 Locking part

[0043] 14 Locking surface

[0044] 15 Axial stop

[0045] 16 Inner surface

[0046] 17 Gap

[0047] 18 Spacer

[0048] 19 Outer surface

Claims

1. An electric machine (1), in particular an electric machine (1) for a motor vehicle, the electric machine comprising: Multiple phases; A plurality of phase connection parts (4 to 6) connected to each phase for the motor (1) to contact a control device, in particular an inverter; and a star conductor (7), characterized in that the star conductor (7) and the phase connection parts (4 to 6) are arranged at different circumferential positions (8, 9) relative to the longitudinal axis (2) of the motor (1).

2. The motor (1) according to claim 1, characterized in that, The star conductor (7) and the phase connection parts (4 to 6) are in particular arranged at the same radial position (11) or different radial positions relative to the axis of rotation of the motor (1).

3. The electric machine (1) according to claim 1 or 2, characterized in that, A protective cover (12) is provided, which at least partially surrounds the star conductor (7).

4. The motor (1) according to claim 3, characterized in that, The protective cover (12) is designed to support the star conductor (7) in a defined position in the housing of the motor (1).

5. The electric machine (1) according to claim 3 or 4, characterized in that, The protective cover (12) has an axial stop (15), which prevents the unintentional loosening of the protective cover (12).

6. The electric machine (1) according to any one of claims 3 to 5, characterized in that, The protective cover (12) has at least one locking part (13), in particular two opposing locking hooks, which is designed to lock the protective cover (12) at the star conductor (7).

7. The electric machine (1) according to any one of claims 3 to 6, characterized in that, The protective cover (12) has at least one spacer part (18), which is designed to position the star conductor (7) in the radial direction.

8. An electric axle drive, in particular for a motor vehicle, comprising an inverter and a motor (1) according to any one of the preceding claims.

9. A motor vehicle, which comprises a motor (1) according to any one of claims 1 to 7 and / or an electric axle drive according to claim 8.

10. Method for manufacturing an electric machine (1), in particular an electric machine (1) for a motor vehicle, the electric machine comprising: Multiple phases; A plurality of phase connection parts (4 to 6) connected to each phase for the motor (1) to contact a control device, in particular an inverter; and a star conductor (7), characterized in that the star conductor (7) and the phase connection parts (4 to 6) are arranged at different circumferential positions relative to the longitudinal axis of the motor (1).

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