Rotor and electric machine

Abstract

The invention relates to a rotor, in particular for a current-excited synchronous machine, which is at least partially embedded in a casting compound, wherein at least one conductor element is provided on the rotor, which forms a winding and is connected to a current collector element, at least between the current collector element and the winding a casting compound is provided, and a connecting section of the conductor element which extends between the winding and the current collector element is isolated from the casting compound by a decoupling element provided there.

Description

Technical Field

[0001] The present invention relates to a rotor, particularly for a current-excited synchronous motor, and a motor. Background Technology

[0002] The mechanical stability of rotor windings poses a significant challenge, particularly in the automotive sector where high speeds are sometimes required. In this regard, DE 102016205813 A1 proposes a method in which a rotor lamination core with rotor windings is placed in a mold and cast by injecting a plastic material. As this material cools, hairline cracks appear, leading to stress in the casting. These cracks can be exacerbated during operation. Cracks can also be generated by the high speeds encountered during operation, regardless of potential prior damage. These cracks, which are not inherently problematic, can be problematic for the conductors or wires forming the windings. Of particular importance are conductor or wire sections that are not directly part of the winding or, more precisely, adjacent to the winding, but rather at the winding output—where the wires leave the original winding to, for example, contact a current collector located on the rotor. In practice, it has been shown that the wires or conductors in these sections frequently break, with this damage attributed particularly to cracks located in the casting material there. Summary of the Invention

[0003] Therefore, the objective of this invention is to propose a rotor and motor that eliminate the aforementioned disadvantages.

[0004] The task is solved by the rotor according to the invention and the motor according to the invention. Other advantages and features are apparent from the description and the accompanying drawings.

[0005] According to the invention, a rotor, particularly a rotor for a current-excited synchronous motor, is at least partially embedded in a casting material. At least one conductor element is provided on the rotor, forming a winding and connected to a current collector element. Casting material is provided at least between the current collector element and the winding, and the connection section of the conductor element extending between the winding and the current collector element is isolated from the casting material by a decoupling element disposed therein. The current collector element is a component disposed on the rotor shaft of the rotor according to one embodiment, and on this current collector element, the conductor elements / wires of the winding are gathered and interconnected. The current collector element is electrically connected to the slip rings of the rotor in a suitable manner. According to a preferred embodiment, the rotor is assembled from multiple laminations. These laminations, for example made of electrical steel sheets, have slots or tabs extending along the rotor axis and alternately arranged in the circumferential direction. Windings are formed in the slots or around the tabs. For electrical contact, current collector elements, or current collectors, are provided on the rotor for electrically connecting the individual conductor elements, especially the wires. Therefore, current collectors are suitably disposed directly or indirectly on the rotor shaft of the rotor. Conductor elements, especially wires, are preferably made of copper, though other materials are conceivable and possible. In the winding region surrounding the contact, the copper wire is well protected by its robust and compact arrangement. However, the copper wire is unprotected in the region leading from the winding itself to the current collector. In other words, the copper wire is essentially exposed there. If, for example, micro-movements occur on the copper wire in this connection section, these micro-movements can be manifested, for example, by the casting material present there, and especially by micro-cracks that may exist there, the conductor element may break in the connection section. Advantageously, a decoupling element is now provided in this region, which decouples or isolates the connection section from the casting material. In other words, the decoupling element prevents the casting material from directly touching, contacting, or abutting the conductor element in the connection section region. Cracks that may exist in the casting material therefore do not cause breakage of the conductor element in this region.

[0006] According to one embodiment, the decoupling element is directly disposed on the connection section. In other words, the decoupling element is preferably disposed directly or indirectly on the conductor element in the connection section region. According to a preferred embodiment, the decoupling element is shaped or designed to completely or at least partially cover the conductor element in the connection section region. Covering can be achieved by pushing on a tubular or flexible decoupling element or by wrapping with a suitable strip or bar material.

[0007] According to one embodiment, the decoupling element is a covering element designed to completely cover the connection segment. According to a preferred embodiment, the covering element is made of at least partially flexible or stretchable material. Preferably, the covering element is a fully enclosed covering element disposed on the conductor element along its longitudinal extension direction.

[0008] According to a preferred embodiment, a textile element, such as a woven fabric or braided material, is used as the material for the covering element. According to one embodiment, a glass fiber woven fabric or glass filament woven fabric is used as the material, and it is particularly preferred to contain a silicone resin component. This silicone resin component advantageously prevents the casting material from bonding with the material of the decoupling element / covering element.

[0009] According to a preferred embodiment, the sheathing element is a glass fiber flexible tube, particularly preferably a glass fiber silicone flexible tube, wherein the silicone component advantageously prevents the casting material from connecting to the sheathing element. Advantageously, one or more conductor elements of the winding are sheathed in the connection section area by the glass fiber flexible tube. The glass fiber flexible tube advantageously acts as a barrier or obstruction against casting material present in this area. It has been shown that this can very effectively prevent wire breakage.

[0010] According to an alternative embodiment, the decoupling element is formed of a flexible layer, wherein preferably the connecting section or conductor element is embedded in the flexible layer.

[0011] According to one embodiment, the elastic layer is made of silicone resin. According to one embodiment, the layer includes a base layer and a cover layer, wherein a connecting section is embedded between the base layer and the cover layer. According to one embodiment, the base layer is first applied to the rotor in the connecting section region. Conductor elements are then disposed, and subsequently, the cover layer is disposed or positioned, so that the conductor elements are advantageously completely covered by the elastic layer in the connecting section region.

[0012] In one alternative embodiment, the conductor element is replaced by a contact element in the connection section. In one embodiment, the contact element is a suitably designed cable connector (Kabelschuh). Preferably, the contact element is an element with greater strength or stability than a conductor element made of wire.

[0013] According to a preferred embodiment, the rotor has multiple connection sections, wherein each connection section is isolated by a decoupling element.

[0014] The present invention also relates to an electric motor comprising a rotor according to the invention. Preferably, the motor is a current-excited synchronous motor. According to a preferred embodiment, the motor is a traction motor for a partially or fully electrified motor vehicle, particularly a car or motorcycle.

[0015] The proposed decoupling element can be advantageously installed quickly. Placement, or installation, can be done manually or by machine, for example, by using a suitable industrial robot. Attached Figure Description

[0016] Other advantages and features will become apparent from the following description of the implementation of the rotor or motor with reference to the accompanying drawings. The drawings are as follows:

[0017] Figure 1 Two views of the rotor are shown, taken along its axis. Detailed Implementation

[0018] Figure 1 The rotor 10 is shown in its upper left half as a view along the rotor axis R. A rectangle indicates a portion, which is enlarged in the lower right half. Here, in particular, a winding 12 formed by conductor elements 14 can be seen. This conductor element 14 is connected to the contact point 22 of the current collector element 20 via a connection section 16. In the region between the contact point 22 and the output terminal of the conductor element 14 from the winding 12—this region is formerly referred to as the connection section 16—the conductor element 14 is essentially “exposed.” According to the invention, the arrangement of decoupling elements is now precisely located in this region. According to one embodiment, for example in the region of the connection section 16, the conductor element 14 is covered by a suitable sheathing element, such as a fiberglass hose, or is wrapped in a suitable manner. Alternatively, a resilient layer can be provided or provided in this region, designed to protect, and in particular surround or cover, the conductor element 14 in the region of the connection section 16. As an alternative, conductor element 14 is replaced by a contact element in the region of connection section 16, which is positioned between conductor element 14 at the output end of winding 12 and contact point 22. It has been shown that by using a decoupling element, wire breaks in this region can be effectively avoided.

[0019] List of reference numerals

[0020] 10 rotors

[0021] 12 windings

[0022] 14 Conductor Elements

[0023] 16 connecting sections

[0024] 20 collector elements

[0025] 22 contact points

[0026] R rotor axis

Claims

1. A rotor (10) wherein the rotor is at least partially embedded in a casting material, wherein, A plurality of conductor elements (14) are provided on the rotor (10), each of the plurality of conductor elements forming a winding (12) and connected to a current collector element (20). At least between the current collector element (20) and each of the windings (12), there is a casting material, and the connection section (16) of each of the plurality of conductor elements (14) extending between the winding (12) and the current collector element (20) is isolated from the casting material by a decoupling element provided there there, so that cracks present in the casting material will not cause the conductor element (14) to break in that area.

2. The rotor (10) according to claim 1, wherein, The decoupling element is directly disposed on the connection section (16).

3. The rotor (10) according to claim 1 or 2, wherein, The decoupling element is a covering element, which is designed to completely cover the connection segment.

4. The rotor (10) according to claim 3, wherein, The covering element is a glass fiber silicone tube.

5. The rotor (10) according to claim 1 or 2, wherein, The decoupling element is composed of an elastic layer, and the connecting section (16) is embedded in the elastic layer.

6. The rotor (10) according to claim 5, characterized in that, The elastic layer is made of silicone resin and includes a base layer and a cover layer, with a connecting section (16) embedded between the base layer and the cover layer.

7. The rotor (10) according to claim 1 or 2, wherein, The conductor element (14) is replaced by a contact element in the connection section (16).

8. The rotor (10) according to claim 1, wherein, The rotor is the rotor of a synchronous motor used for current excitation.

9. An electric motor comprising a rotor (10) according to any one of claims 1 to 8.

Images