DE102011100843B4 - Electric motor, having stator windings encapsulated with potting compound - Google Patents

Abstract

Electric motor, having stator windings encapsulated with potting compound,
wherein each stator winding is assigned a rail part (1),
wherein, for contacting the stator windings, an end region of a respective stator winding wire of the respective stator winding is electrically connected to the associated rail part (1), in particular crimped, welded, soldered, screwed and/or riveted,
wherein each rail part (1) encapsulated by casting compound has a bent, in particular upwardly bent, tab (2) which protrudes from the casting compound,
wherein the tabs of the rail parts (1) of the respective stator windings are arranged offset from one another in the circumferential direction, in particular spaced apart from one another in the circumferential direction,
wherein the rail parts (1) are arranged axially spaced from one another, wherein the end regions of the winding wires are contacted at different axial positions,
wherein the rail part (1) has recesses (3) to each of which a stator winding wire end region is electrically connected,
characterized in that
the recesses (3) are arranged on a radial inner side of the rail part (1),
wherein the rail parts (1) are surrounded at a smaller radial distance than the winding head (23) and are thus protected by the latter and the associated stator housing.

Description

The invention relates to an electric motor having stator windings encapsulated with a casting compound.

It is known that the end portions of stator winding wires of an electric motor are connected to electrical supply lines.

From the DE 11 2008 001 219 T5 An electric motor for a hybrid vehicle is known in which an arcuately curved busbar arrangement is disclosed for connecting the windings.

From the FR 2 837 993 A1 The closest state of the art is a stator in which connecting parts designed as busbars are each provided in the same axial area.

From the EP 0 667 279 A1 An actuator for wheel control is known.

From the DE 10 2004 036 368 A1 an electric motor is known.

The invention is therefore based on the object of developing an electric motor with regard to its stator contact in a manner that is simple and cost-effective to manufacture.

According to the invention, the object is achieved in the electric motor according to the features specified in claim 1.

The advantage here is that electrical contact can even be made with a supply line insulated with silicone. This is because the silicone is not subjected to thermal stress, which could cause it to spread and soil the housing or contaminate the potting compound. This ensures a secure electrical connection. Furthermore, the remaining rail section is potted and thus protected from corrosion, while also being surrounded by the heat-dissipating potting compound. This allows very high currents to pass through the rail section. The circumferential offset enables particularly barrier-free contact, as there is plenty of space available for contacting.

According to the invention, the rail parts are arranged axially spaced from one another. This is advantageous because it allows for simple assembly and a high insulation distance.

In an advantageous embodiment, the axial region covered by the rail parts at least partially covers the region covered by a winding overhang, in particular the deflection region, of a stator winding, in particular at least partially the region covered by winding overhangs, in particular the deflection regions, of the stator windings. This is advantageous in that no additional axial installation space is required and the contact areas are surrounded by a smaller radial distance than the winding overhang and thus protected by the winding overhang and the associated stator housing. This also increases safety.

In an advantageous embodiment, an electrical supply line is electrically connected to the tab, in particular by crimping, welding, soldering, screwing, and/or riveting. This allows for the use of a simple and cost-effective connection technology and allows for the conduction of high currents.

In an advantageous embodiment, two or more stator winding wires are electrically connected to the rail part, in particular by crimping, welding, soldering, screwing, and/or riveting. This is advantageous because the stator winding wires can be interconnected, for example, including a star point connection of the three stator windings U, V, and W.

In an advantageous embodiment, the rail part has at least one recess, in particular at least one slot opening into the edge region of the rail part, for electrical connection to a respective stator winding wire end region. This is advantageous in that a particularly simple connection is possible, since the end region can be threaded into the slot and then connected, for example, by welding or crimping.

In an advantageous embodiment, the rail part is curved, in particular arcuately curved, with the tab protruding from the plane of curvature. It is advantageous that the rail part can be surrounded by casting compound, with the tab protruding from the casting compound.

According to the invention, the recess(es) are arranged on the radial inner side of the rail part. This allows for particularly simple contacting, as the rail part can be arranged at a large radial distance and thus far away from the motor rotor.

In an advantageous embodiment, the tab is oriented in the axial direction, i.e., parallel to the rotor axis of the motor, and the remaining rail section is oriented in the circumferential direction. This is advantageous because the contact can be made in the axial direction.

In an advantageous embodiment, several similar rail parts are arranged in the casting compound, wherein the respective tabs are arranged offset from one another in the circumferential direction and protrude from the casting compound surrounding the stator windings,

In particular, each rail section has a tab bent out from the plane of curvature of the curved rail section. This allows for space-saving contacting, i.e., one that requires minimal installation space.

In an advantageous embodiment, the rail part is designed in the shape of a circular ring, with the tab being bent out of the plane of the circular ring, in particular bent upwards. Advantageously, the rail part can be manufactured as a stamped and bent part or as a cast part, and the tab can be bent out or formed by casting.

In an advantageous embodiment, the rail part is a stamped and bent part. This allows for cost-effective production.

In an advantageous embodiment, the rail part is made of copper-containing material, particularly copper. The advantage here is that low ohmic losses occur.

In an advantageous embodiment, the casting compound is thermally conductive and electrically insulating. This is advantageous because the rail component can be subjected to high currents.

In an advantageous embodiment, the rail section is designed to permanently conduct more than 100 amperes, in particular more than 400 amperes. This is advantageous because high currents can be conducted.

Further advantages emerge from the dependent claims. The invention is not limited to the combination of features in the claims. Further possible combinations of claims and/or individual claim features and/or features of the description and/or the figures will become apparent to those skilled in the art, particularly from the problem and/or the problem posed by comparison with the prior art.

• In der 1 ist ein Schienenteil 1 gezeigt, dass halbkreisförmig gebogen ist und ein aus der Ebene des Halbkreises hochgebogene Lasche 2 aufweist.

The invention will now be explained in more detail using schematic illustrations:

• In the 1 a rail part 1 is shown which is bent in a semicircle shape and has a tab 2 bent up from the plane of the semicircle.

In the 2 A cross-section through a section of the electric motor is shown.

In addition, recesses 3 spaced apart from one another are arranged in the circumferential direction of the semicircle on the rail part 1.

The rail part is used for stator contact in an electric motor. The stator winding wires are brought to the rail part 1, preferably to its recesses 3, and electrically connected, for example, by crimping, welding, soldering, screwing, and/or riveting.

Several winding wires, for example the stator winding U, V and/or W, can be connected to the rail part 1.

In this way, an electrical connection between two stator winding wires is possible.

The connection of an electrical supply line is made possible by connecting it to the tab. Here, for example, the electrical supply line is connected to the tab 2 by crimping, welding, soldering, screwing, and/or riveting.

The stator winding of the electric motor is encapsulated with an electrically insulating casting compound. The rail section 1, including the electrical connection areas with the stator winding wires, is also encapsulated, but the raised tab 2 protrudes from the casting compound. This allows for electrical contact with the tab 2 even after encapsulation.

Heat, for example from the stator winding or ohmic heat generated in the rail part 1 or at the connection points, can also be dissipated via the casting compound to the stator laminated core in which the stator winding is provided.

The electrical supply line can therefore be siliconized, as there is no disturbing evaporating silicone during the casting process. and/or when welding the electrical supply cable to the bent-up tab 2, the evaporating silicone does not disturb the casting compound insulation.

Preferably, the rail part 1 is made of copper-containing material, in particular copper.

As in 2 As shown, the motor has a shaft 20, in particular a rotor shaft, on which a rotor core 21 is arranged. The rotor shaft is mounted in a housing 24, which forms a housing to protect the stator core 22.

The stator windings are arranged in the stator core 22, which project axially with their respective winding head 23 from the stator core 22 and with 2 are cast with a casting compound not shown.

The end sections of the stator winding wires are guided onto the rail parts 1, each of whose upwardly bent tabs 2 project axially in the direction of the rotor axis. 2 A protruding tab 2 is clearly shown for this purpose.

Preferably, the tabs 2 of the other rail parts 1 are designed in the same way and the rail parts 1 are arranged offset from one another in the circumferential direction, so that the tabs 2 protrude from the casting compound at different angular areas in the circumferential direction and can thus be contacted there in a simple manner and at a good distance from one another.

The rail parts are therefore spaced apart from each other in the axial direction so that the end regions of the winding wires are contacted at different axial positions.

The end regions of the stator winding wires and the rail parts 1 with tabs 2 are arranged in the axial region in which the projecting winding heads 23 extend, wherein they are arranged at a smaller radial distance than the winding heads.

The potting compound, which is arranged between the stator winding and the rail sections, is electrically insulating and dissipates the heat from the rail section and/or the stator winding to the motor's stator housing. Thus, the potting compound not only improves mechanical stability against vibrations but also improves heat dissipation.

list of reference symbols

1

Rail part

2

tab

3

recess

20

Wave

21

Rotor lamination package

22

Stator lamination stack

23

winding head

Claims (13)

An electric motor comprising stator windings encapsulated with potting compound, each stator winding being assigned a rail part (1), wherein, for contacting the stator windings, an end region of a respective stator winding wire of the respective stator winding is electrically connected to the assigned rail part (1), in particular crimped, welded, soldered, screwed and/or riveted, wherein the rail part (1) encapsulated with potting compound has a bent, in particular upturned, tab (2) which protrudes from the potting compound, wherein the tabs of the rail parts (1) of the respective stator windings are arranged offset from one another in the circumferential direction, in particular spaced from one another in the circumferential direction, wherein the rail parts (1) are arranged axially spaced from one another, wherein the end regions of the winding wires are contacted at different axial positions, wherein the rail part (1) has recesses (3), to each of which a stator winding wire end region is electrically connected, characterized in that the recesses (3) are arranged on a radial inner side of the rail part (1), wherein the rail parts (1) are surrounded at a smaller radial distance than the winding head (23) and are thus protected by the latter and the associated stator housing. Electric motor according to Claim 1 , characterized in that the axial region covered by the rail parts (1) at least partially covers the region covered by a winding head (23), in particular a deflection region, of a stator winding, in particular at least partially covers the region covered by winding heads (23), in particular deflection regions, of the stator windings. Electric motor according to at least one of the preceding claims, characterized in that an electrical supply line is electrically connected to the tab (2), in particular crimped, welded, soldered connected, screwed and/or riveted. Electric motor according to at least one of the preceding claims, characterized in that two or more stator winding wires are electrically connected to the rail part (1), in particular crimped, welded, soldered, screwed and/or connected by means of a rivet. Electric motor according to at least one of the preceding claims, characterized in that the recesses (3) are each designed as a slot opening into the edge region of the rail part (1). Electric motor according to at least one of the preceding claims, characterized in that the rail part (1) is curved, in particular curved in an arcuate manner, the tab (2) protruding from the plane of curvature. Electric motor according to at least one of the preceding claims, characterized in that the tab (2) is oriented in the axial direction, i.e. parallel to the rotor axis of the motor, in particular and the remaining rail part (1) in the circumferential direction. Electric motor according to at least one of the preceding claims, characterized in that a plurality of similar rail parts (1) are arranged in the casting compound, wherein the respective tabs are arranged offset from one another in the circumferential direction and protrude from the casting compound surrounding the stator windings, in particular wherein each rail part (1) has a tab (2) bent out of the plane of curvature of the curved rail part (1). Electric motor according to at least one of the preceding claims, characterized in that the rail part (1) is designed in the shape of a circular ring section, wherein the tab (2) is bent out of the plane of the circular ring, in particular bent upwards. Electric motor according to at least one of the preceding claims, characterized in that the rail part (1) is a stamped and bent part or, together with the upwardly bent tab (2), is manufactured in one piece as a cast part, in particular wherein a very high current intensity can be conducted in the bending area. Electric motor according to at least one of the preceding claims, characterized in that the rail part (1) is made of copper-containing material, in particular copper. Electric motor according to at least one of the preceding claims, characterized in that the casting compound is thermally conductive and electrically insulating. Electric motor according to at least one of the preceding claims, characterized in that the rail part (1) is designed to be suitable for the permanent conduction of more than 100 amperes, in particular more than 400 amperes.

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