阅读说明：本技术 尤其用于车辆的电动机 (Electric motor, in particular for a vehicle ) 是由 米尔科·霍赖茨 汉斯-乌尔里希·施托伊雷尔 约瑟夫·松塔格 斯托扬·马尔基奇 安德烈·利琴 于 2018-05-18 设计创作，主要内容包括：本发明涉及一种电动机(1),尤其是用于车辆,包括转子(3)和定子(2),所述转子(3)能够绕限定所述电动机(1)的轴向方向(A)的旋转轴线(D)旋转,所述定子(2)包括多个定子绕组(6),具有冷却剂分配腔室(4)和与所述冷却剂分配腔室在轴向上具有距离地布置的冷却剂收集腔室(5),所述冷却剂分配腔室(4)通过能够流过有冷却剂(K)的至少一个冷却通道(10)与所述冷却剂收集腔室(5)流体连通,为了冷却定子绕组(6),至少一个定子绕组(6)包含在由电绝缘塑料组成的塑料物质(11)中,为了热联接,所述冷却剂分配腔室(4)和/或所述冷却剂收集腔室(5)布置在至少一个定子绕组(6)的第一和/或第二轴向端部(14a,14b)中,为了热联接至所述至少一个定子绕组(6),所述冷却剂分配腔室(4)和/或所述冷却剂收集腔室(5)至少部分地布置在所述塑料物质(11)中。(The invention relates to a electric motor (1), in particular for a vehicle, comprising a rotor (3) and a stator (2), the rotor (3) being rotatable about a rotational axis (D) defining an axial direction (A) of the electric motor (1), the stator (2) comprising a plurality of stator windings (6) having a coolant distribution chamber (4) and a coolant collection chamber (5) arranged axially at a distance from the coolant distribution chamber, the coolant distribution chamber (4) being in fluid communication with the coolant collection chamber (5) via at least cooling channels (10) through which a coolant (K) can flow, for cooling the stator windings (6) at least stator windings (6) being contained in a plastic substance (11) consisting of an electrically insulating plastic, for thermal coupling the coolant distribution chamber (4) and/or the coolant collection chamber (5) being arranged in a and/or a second axial end (14a, 14b) of at least stator windings (6), for thermal coupling the coolant distribution chamber (4) and/or the coolant collection chamber (6) being arranged at least partially in the stator windings (11).)

1, electric motor (1), in particular for a vehicle,

-comprising a rotor (3), which rotor (3) is rotatable around a rotation axis (D) defining an axial direction (A) of the electric motor (1), and which electric motor (1) comprises a stator (2) having stator windings (6),

-comprising a coolant distribution chamber (4) and a coolant collection chamber (5) arranged axially with a distance therefrom, wherein, for the purpose of cooling the stator windings (96), the coolant distribution chamber (4) is in fluid communication with the coolant collection chamber (5) through at least cooling channels (10) through which a coolant (K) can flow, wherein, for the purpose of thermal coupling, at least stator windings (6) are incorporated into a plastic composition (11) consisting of an electrically insulating plastic,

-wherein the coolant distribution chamber (4) and/or the coolant collection chamber (5) are arranged in the region of the and/or second axial end (14a, 14b), preferably in the axial extension of the and/or second end (14a, 14b), of at least stator windings (6),

-wherein the coolant distribution chamber (4) and/or the coolant collection chamber (5) are at least partially arranged in the plastic composition (11) for the purpose of thermal coupling with the at least stator windings (6).

2. The motor as set forth in claim 1,

it is characterized in that

The coolant distribution chamber (4) and/or the coolant collection chamber (5) are arranged radially outside the and/or second end (14a, 14b) of the at least stator windings (6).

3. The motor according to claim 1 or 2,

it is characterized in that

The coolant distribution chamber (4) and/or the coolant collection chamber (5) have an annular geometry in a cross section perpendicular to the rotational axis (D) of the rotor (3).

4. The motor of any of claims 1-3,

it is characterized in that

The plastic composition (11) at least partially defines the coolant distribution chamber (4) and/or the coolant collection chamber (5).

5. The motor of any of the preceding claims,

it is characterized in that

The coolant distribution chamber (4) and/or the coolant collection chamber (5) are formed by cavities (41a, 41b) at least partially, preferably completely, contained in the plastic composition (11).

6. The motor of any of the preceding claims,

it is characterized in that

The at least cooling channels (10) are also contained in at least of the plastic compositions (11) consisting of the electrically insulating plastic.

7. The motor of any of the preceding claims,

it is characterized in that

-the stator (2) has stator teeth (8) extending in the axial direction (A) and arranged at a distance from each other in a circumferential direction (U) of the rotor (3), the stator teeth carrying the stator windings (6),

-wherein the plastic composition (11) is arranged in the gap (9) realized between two stator teeth (8) adjacent in the circumferential direction (U) starting from the at least cooling channels (10) and the at least stator windings (6).

8. The motor as set forth in claim 7,

it is characterized in that

-the interspace (9) comprises a subspace (9c) in which the at least stator windings (6) are arranged and a second subspace (9d) in which the at least cooling channels (10) are arranged,

-a positioning aid (27) is arranged between the two subspaces (9c, 9d), by means of which positioning aid the at least cooling channels (10) can be positioned in the second subspace (9 d).

9. The motor as set forth in claim 8,

it is characterized in that

The positioning aid (27) comprises two projections (28a, 28b) realized at two stator teeth (8a, 8b) adjacent in the circumferential direction (U),

-the two projections (28a, 28b) face each other in the circumferential direction (U) and protrude into the interspace (9) for the purpose of positioning the cooling channel (10).

10. The motor of any of the preceding claims,

it is characterized in that

-the plastic composition (11) consists of a single plastic (material) in at least voids (9),

-an additional electrically insulating piece (15) consisting of an electrically insulating material is arranged in the interspace (9).

11. The motor as set forth in claim 10, wherein,

it is characterized in that

The additional electrical insulation (15) is arranged between the stator winding (6) and the stator teeth (8), preferably between the plastic composition (11) and the stator teeth (8).

12. The motor of any of the preceding claims,

it is characterized in that

-the electrically insulating plastic comprises or is a thermoset, and/or

-the electrically insulating plastic comprises or is a thermoplastic.

13. The motor of any of claims 7-12,

it is characterized in that

At least cooling channels (10) are provided with the plastic composition (11) arranged therein in at least interspaces (9), preferably in each interspace (9), between two stator teeth (8a, 8b) which are adjacent in each case in the circumferential direction (U).

14. The motor of any of the preceding claims,

it is characterized in that

The at least cooling channels (10) are arranged in the interspace (9) radially outside and/or radially inside the respective stator winding (6).

15. The motor of any of the preceding claims,

it is characterized in that

The at least cooling channels (10) are realized as a tube body (16) surrounding a tube body interior (22),

wherein at least dividing elements (18) are formed at the tube body (16) and divide the tube body interior (22) into at least two partial cooling channels (19) that are fluidly separated from each other.

16. The motor as set forth in claim 15, wherein,

it is characterized in that

The tube body (16) is embodied as a flat tube (17) having two wide sides (20) and two narrow sides (21).

17. The motor according to claim 15 or 16,

it is characterized in that

The tube body (16) is embodied as a flat tube (17),

wherein, in a cross section perpendicular to the axial direction (A), at least broad sides (20) of the flat tube (17) extend substantially perpendicular to the radial direction (R).

18. The motor of any of the preceding claims,

it is characterized in that

The at least cooling channels (10) are arranged completely in the plastic composition (11).

19. The motor of any of the preceding claims,

it is characterized in that

The at least cooling channels (10) consist of at least perforations (40), preferably of a plurality of perforations (40), which are provided in the plastic composition (11) and through which a coolant (K) can flow.

20. The electric motor as set forth in claim 19,

it is characterized in that

At least perforations (40) have a rectangular geometry in a cross section perpendicular to the axial direction (A), the rectangle having two broad sides (20) and two narrow sides (21).

21. The motor of any of the preceding claims,

it is characterized in that

At least cooling channels (10) are arranged in the stator body (7) and are formed by at least perforations (40) through which a coolant (K) can flow.

22. The motor as set forth in claim 21,

it is characterized in that

The perforations (40) forming the cooling channel (10) are realized to be open towards the interspace (9) and closed in a liquid-tight manner by a plastic composition (11) arranged in the interspace (9).

23. The motor of any of the preceding claims,

it is characterized in that

At least cooling channels (10, 10b) are provided in the composite (11) and at least cooling channels (10, 10b) are provided in the stator body (7).

24. The motor of any of the preceding claims,

it is characterized in that

The stator (2) is arranged along the axial direction (A) between -th and second end dust covers (25a, 25b) that are axially opposite to each other,

wherein portion of the coolant distribution chamber (4) is disposed in the end dust cap (25a) and/or portion of the coolant collection chamber (5) is disposed in the second end dust cap (25b),

wherein the two end dust caps (25a, 25b) are preferably realized as separate components at least partially defining the coolant distribution chamber (4) and/or the coolant collection chamber (5), respectively.

25. The motor of any of the preceding claims,

it is characterized in that

-a coolant supply (35) is realized in the th end dust cover (25a) and fluidly connects the coolant distribution chamber (4) to a coolant inlet (33) provided outside, preferably at an end side, of the th end dust cover (25a),

-wherein preferably the coolant supply device (35) is thermally connected to a rotatably mounted th shaft bearing (32a) for the stator (2), the th shaft bearing being provided in the th end dust cap (25a) and/or

-a coolant discharge (36) is realized in the second end dust cap (25b) and fluidly connects the coolant collection chamber (5) to a coolant outlet (34) provided outside, preferably at an end side, of the second end dust cap (25b),

-wherein preferably said coolant discharge means (36) is thermally connected to a rotatably mounted second shaft bearing (33a) for said stator (2), said second shaft bearing being provided in said second end dust cap (25 b).

26. The motor of any of the preceding claims,

it is characterized in that

The plastic composition (11) is an injection-molded composition consisting of the electrically insulating plastic.

27. The motor of any of the preceding claims,

it is characterized in that

The plastic composition is realized in the form of bodies.

28. The motor of any of the preceding claims,

it is characterized in that

-the stator (2) comprises a preferably annular stator body (7),

-the plastic composition (11) consisting of the electrically insulating plastic is arranged at an outer circumference side (30) of the stator body (7), and preferably forms an outer coating (11.1) of the outer circumference side (30).

29. The motor of any of the preceding claims,

it is characterized in that

The plastic composition (11) at least partially surrounds at least winding sections of the stator winding (6) that project axially from the air gap (9) and in this case partially defines the coolant distribution chamber (4) and/or the coolant collection chamber (5) such that the winding sections are electrically insulated from the coolant (K) during operation of the electric motor (1).

30. The motor of any of the preceding claims,

it is characterized in that

The coolant distribution chamber (4) is in fluid communication with the coolant collection chamber (5) through a plurality of cooling channels (10).

31. The motor as set forth in claim 30, wherein,

it is characterized in that

The plurality of cooling channels (10) extend at a distance from each other along the axial direction (A).

32. The motor according to claim 30 or 31,

it is characterized in that

The cooling channels (10) are arranged at a distance from one another in the circumferential direction (U) of the stator (2).

33. The motor of any of the preceding claims,

it is characterized in that

The coolant distribution chamber (4) and/or the coolant collection chamber (5) are arranged exclusively in the axial extension of the stator body (7) or stator (2) adjacent thereto and preferably do not protrude beyond the latter in the radial direction (R) of the stator body (7) or stator (2).

34. The motor of any of the preceding claims,

it is characterized in that

At least stator windings (6) are embodied in such a way that they are electrically insulated from the coolant (K) and from the stator body (7) at least in the region within the respective air gap (9) during operation of the electric motor (1).

35. The electric motor as set forth in claim 34,

it is characterized in that

The at least stator windings (6) are electrically insulated from the stator body (7), preferably also from the stator teeth (8) defining the interspace (9), particularly preferably completely formed by the plastic composition (11) and/or by the additional insulation (15).

36. The motor of any of claims 10-35,

it is characterized in that

The additional electrical insulation (15) extends within the gap over the entire length of the gap measured along the axial direction (a) such that it insulates the stator winding (6) from the stator body (7) and from the stator teeth (8) defining the respective gap (9).

37. The motor of any of claims 10-36,

it is characterized in that

The additional electrical insulation (15) encapsulates the stator winding (6) within the gap (9) at least over the entire length of the gap (9) along its circumference.

38. The motor according to claim 36 or 37, if dependent again on claim 15,

it is characterized in that

The at least stator windings (6) are electrically insulated from the cooling channel (10) which is realized as a tube body (16) by the plastic compound (11) and/or the additional insulation (15).

39. The motor of any of the preceding claims,

it is characterized in that

The stator winding (6) is part of a distributed winding.

Vehicle, in particular motor vehicle, of the type 40, , comprising at least electric motors (1) according to any of the preceding claims .

Technical Field

The present invention relates to electric motors, in particular for vehicles, and to vehicles comprising such electric motors.

Background

This type of electric motor can generally be an electric motor or a generator. The motor can be implemented as an outer rotor or as an inner rotor.

For example, generic type of electric motor is known from US 5,214,325, comprising a housing surrounding an interior and having a casing extending in the circumferential direction of the housing and radially defining the interior, a rear side wall at the side of the axial defining the interior in the axial direction, and a front side wall at the side of the axial other defining the interior in the axial direction.

It is known from conventional electric motors to equip the latter with cooling means for cooling the stator, in particular the stator windings, such cooling means comprising or more cooling channels through which a coolant flows and which are arranged in the stator in the vicinity of the stator windings.

In this case, only with a significant structural complexity, an effective heat transfer from the stator to the coolant flowing through the cooling channels proves to be disadvantageous. However, this has a disadvantageous effect on the manufacturing cost of the motor.

Disclosure of Invention

The object of the present invention is therefore to provide improved embodiments for an electric motor, in which this disadvantage is largely eliminated or even completely eliminated.

This object is achieved by the subject matter of the independent claims. The dependent claims relate to preferred embodiments.

The basic idea of the invention is therefore to incorporate the stator windings of the electric motor into a plastic composite consisting of plastic, in which there are also provided coolant distribution and coolant collection chambers for the coolant which absorbs the waste heat generated by the stator windings as a result of thermal interaction. In this case, plastic is used as a heat transfer medium for transferring heat from the stator windings to the coolant.

In this way, particularly good heat transfer between the stator windings and the coolant passing through the stator occurs. This is particularly effective if a plastic with high thermal conductivity is used. In particular, so-called thermosetting plastics are suitable for this purpose. Since plastic also generally has the property of electrical insulation, this at the same time ensures that the stator winding to be cooled is not electrically short-circuited in an undesirable manner. Thus, even in case of high evolution of waste heat in the stator (such as e.g. occurring during operation of the electric motor), it can be ensured that the generated waste heat can be dissipated from the stator. Damage or even destruction of the motor as a result of overheating of the stator can thus be avoided. The plastic composition in which the coolant distribution chamber and/or the coolant collection chamber are/is formed, respectively, can be produced by injection molding, in which plastic is injection molded around the stator winding to be cooled. The inclusion of the stator windings and cooling channels into the plastic composition thus results to be very simple.

For the purpose of cooling the stator windings, the coolant, which originates from a coolant collection chamber realized in the plastic composition, can be distributed between a plurality of cooling channels in which the coolant absorbs waste heat from the stator windings as a result of thermal interaction. After flowing through the cooling channels, the coolant can be collected in a coolant collection chamber. According to the invention, since the coolant distribution chamber and the coolant collection chamber are arranged in the plastic composition, the coolant present in the coolant distribution chamber can be used for cooling the stator windings before it has been distributed between the cooling channels. The same is correspondingly valid for the coolant collected in the coolant collection chamber after flowing through the cooling channel. Since the coolant distribution chamber and/or the coolant collection chamber are thus arranged directly adjacent to the stator windings to be cooled, an effective thermal coupling of the coolant distribution chamber and/or the coolant collection chamber, respectively, to the stator windings to be cooled is achieved in this way.

The electric motor according to the invention, in particular for a vehicle, comprises a rotor which can rotate about an axis of rotation, the axis of rotation defining an axial direction of the electric motor, the electric motor further comprising a stator having stator windings, the electric motor further comprising a coolant distribution chamber and a coolant collection chamber arranged at a distance from the coolant distribution chamber in the axial direction, it being possible for a coolant to flow through the coolant distribution chamber for the purpose of cooling waste heat generated by the stator windings, and the coolant distribution chamber being in fluid communication with the coolant collection chamber via at least cooling channels.

According to preferred embodiments, the coolant distribution chamber and/or the coolant collection chamber surround the and/or the second axial end of at least stator windings in a U-shaped or C-shaped manner along the axis of rotation in longitudinal section, in this manner, in particular the end which is subjected to a thermal load is in fact surrounded by the coolant distribution chamber and/or by the coolant collection chamber, with the result that a particularly good thermal coupling of the coolant to the ends of the respective stator windings can be achieved.

Particularly preferably, the coolant distribution chamber and/or the coolant collection chamber have a U-shaped or C-shaped geometry in the longitudinal section in the axial direction.

In advantageous developments, the coolant distribution chamber and/or the coolant collection chamber are also arranged radially outside the and/or the second end of at least stator windings.

Conveniently, the coolant distribution chamber and/or the coolant collection chamber can have an annular geometry in a cross section perpendicular to the axis of rotation of the rotor. This allows a plurality of cooling channels to be arranged with a distance to each other along the circumferential direction along the stator.

It is particularly preferred that at least plastic compositions at least partially define the coolant distribution chamber and/or the coolant collection chamber.

According to a further advantageous embodiment, the coolant distribution chamber and/or the coolant collection chamber is realized by a cavity which is at least partially, preferably completely, provided in the plastic composition. The provision of a separate enclosure or housing for defining the coolant distribution chamber and/or the coolant collection chamber can thus be excluded. This is associated with significant cost advantages.

According to preferred embodiments, at least cooling channels are also contained in at least plastic compositions consisting of electrically insulating plastic, which ensures a good thermal coupling of the coolant flowing through the cooling channels with the associated stator windings.

In accordance with a further advantageous embodiments, the stator has stator teeth which extend in the axial direction and are arranged at a distance from one another in the circumferential direction, said stator teeth carrying stator windings, hi this embodiment, the plastic composition is arranged with at least cooling channels and at least stator windings in the interspace which is realized between two stator teeth which are adjacent in the circumferential direction.

A further preferred embodiment provides for the air gap to be divided into a th and a second subspace, in this configuration at least stator windings are arranged in the th subspace at least cooling channels are arranged in the second subspace A positioning aid is realized between the two subspaces, by means of which at least cooling channels can be positioned in the second subspace.

In advantageous developments of the construction, the positioning aid comprises two projections realized at two circumferentially adjacent stator teeth, the two projections facing each other in the circumferential direction of the rotor and protruding into the interspace for the purpose of positioning the cooling channel.

According to preferred embodiments, the plastic compound arranged in the interspace consists of a single plastic material, in which embodiment an additional electrical insulation consisting of an electrically insulating material is arranged in the interspace, preferably between the stator winding or the plastic compound and the stator teeth.

Conveniently, the electrically insulating plastic of the plastic composition comprises or is a thermoset. Alternatively, the electrically insulating plastic of the plastic composition can comprise or be a thermoplastic. Combinations of thermosets and thermoplastics are also conceivable in further variants.

Conveniently, the plastic composition substantially completely fills the void. In this way the formation of undesired voids (e.g. in the form of reduced air gaps which would lead to undesired heat transfer) is avoided.

According to preferred embodiments, at least plastic compositions project axially from the interspace, preferably on both sides, the plastic compositions can thus be used to realize the coolant distribution chamber and/or the coolant collection chamber.

According to a further preferred embodiments, at least cooling channels are arranged radially outside and/or radially inside the respective stator winding in the air gap, which enables a space-saving arrangement of the cooling channels in the vicinity of the stator winding to be cooled, as a result of which the electric motor requires only a small constructional space for the cooling of the stator winding.

preferred configurations propose to realize at least cooling channels as a tube body surrounding the interior of the tube body in this variation, at least dividing elements are molded at the tube body and divide the interior of the tube body into at least two partial cooling channels that are fluidly separated from each other.

Conveniently, the tubular body can be realized as a flat tube having two wide sides and two narrow sides.

The beneficial developments propose to realize the tube body as a flat tube which extends in the axial direction and has two broad sides and two narrow sides in a cross section perpendicular to the axial direction conveniently at least broad sides of the flat tube extend perpendicular to the radial direction in a cross section perpendicular to the axial direction in which case the length of the two broad sides can preferably be at least four times, preferably at least ten times, the length of the two narrow sides.

Particularly preferably, at least cooling channels are arranged completely in the plastic composite consisting of plastic.

According to a further preferred embodiment, the stator is formed in an annular manner in a cross section perpendicular to the axial direction and has stator teeth extending in the axial direction and arranged at a distance from each other in the circumferential direction of the stator, said stator teeth carrying stator windings.

According to a further preferred embodiment, at least cooling channels are formed by at least perforations, preferably a plurality of perforations, which are provided in the plastic composition and through which a coolant can flow, particularly preferably a plurality of such perforations are provided.

In this way, the advantageous geometry of the flat tubes is taught to the perforations, which in turn allows a space-saving arrangement of the cooling channels on the proximal side of the stator windings to be cooled.

According to a further preferred embodiment, at least cooling channels are arranged in the stator body and are formed by at least perforations through which coolant can flow, which perforations can be realized in the form of through-holes which are introduced into the stator body during the manufacturing process of the electric motor by means of suitable drilling tools.

In a further preferred embodiment, the perforations forming the cooling channels are realized open towards the interspace. Furthermore, the perforation is closed in a liquid-tight manner by the plastic composition arranged in the interspace. In this variant, the perforations can be produced particularly simply, which is associated with cost advantages during production.

Conveniently, at least cooling channels are arranged in the stator body in the area between two stator teeth adjacent with respect to the circumferential direction this enables arranging the cooling channels in the vicinity of the stator winding to be cooled, which improves the heat transfer from the stator winding to the cooling channels.

According to another preferred embodiments, at least cooling channels are provided in the plastic composite and at least further cooling channels are provided in the stator body.

According to another preferred embodiment, the stator is disposed along the axial direction between and second end dust caps positioned opposite each other along the axial direction in this embodiment, portions of the coolant distribution chamber are disposed in the th end dust cap, alternatively or additionally portions of the coolant collection chamber are disposed in the second end dust cap.

According to another preferred embodiments, the coolant supply means is implemented in the end dust cap and fluidly connects the coolant distribution chamber with a coolant inlet port disposed outboard (preferably on the end side) of the end dust cap, further, the coolant exhaust means is implemented in the second end dust cap and fluidly connects the coolant collection chamber with a coolant outlet port disposed outboard (preferably on the end side) of the second end dust cap, it is particularly preferred that the coolant supply means is thermally connectable to a th shaft bearing for rotatable mounting of the stator, said th shaft bearing being disposed in the th end dust cap.

Particularly preferably, the plastic composition is an injection-molded composition consisting of an electrically insulating plastic. The use of injection molding processes simplifies and speeds up the manufacture of plastic compositions. This results in a cost advantage during the manufacture of the motor.

Particularly preferably, the entire plastic composition, that is to say in particular the plastic composition arranged in the interspace between the stator teeth and the plastic composition defining the coolant distribution chamber and the coolant collection chamber, is contained in an integral manner. This measure simplifies the manufacture of the electric motor, which is associated with cost advantages.

The stator can thus be electrically insulated from the surroundings, thus eliminating the provision of a separate housing for accommodating the stator body.

Since the coolant distribution chamber and/or the coolant collection chamber are thus arranged directly adjacent to the stator windings to be cooled with respect to the axial direction, an effective thermal coupling of the coolant distribution chamber and/or the coolant collection chamber to the stator windings to be cooled is achieved in this way.

According to a further preferred embodiment, the coolant collection chamber and/or the coolant distribution chamber adjoin at least stator windings, preferably and/or the second axial end of the at least stator windings, respectively, radially on the outside and/or radially on the inside and axially on the end face.

According to preferred embodiments, the plastic composition at least partially surrounds at least winding portions of at least stator windings projecting axially from the air gap of the stator body, and in this case partially defines the coolant distribution chamber and/or the coolant collection chamber, so that said winding portions of the stator windings are electrically insulated from the coolant.

According to advantageous developments, the coolant distribution chamber is in fluid communication with the coolant collection chamber through a plurality of cooling channels.

Conveniently, the plurality of cooling channels extend at a distance from each other along the axial direction. This measure ensures that all axial portions of the stator winding are cooled.

Preferably, the cooling channels are arranged with a distance to each other in the circumferential direction of the stator. This measure ensures that all stator windings are cooled in the circumferential direction.

According to another preferred embodiments, the coolant distribution chamber and/or the coolant collection chamber are arranged in the axial extension of the stator body adjacent thereto.

It is particularly preferred that at least stator windings are included, so that they are electrically insulated from the coolant and from the stator body at least in the region within the respective air gap during operation of the electric motor.

It is particularly expedient for at least stator windings to be formed entirely of a plastic composition and/or by the additional insulation already described with respect to the stator body, preferably also with respect to the stator teeth which define the air gap.

According to another preferred embodiments, the additional electrical insulation extends within the gap over the entire length of the gap measured in the axial direction, such that it insulates the stator windings from the stator body and from the stator teeth defining the gap.

According to advantageous developments, an additional electrical insulation encloses the stator within the gap, at least over the entire length of the gap along its circumference.

In particularly preferred embodiments, at least stator windings are also electrically insulated from the cooling channel realized as a tube body.

Particularly preferably, the stator winding can be the part of the distributed winding.

The invention also relates to kinds of vehicles, in particular motor vehicles, which comprise an electric motor as described above.

The important features and advantages of the invention further are apparent from the dependent claims, the drawings and the associated description with reference to the drawings.

It goes without saying that the features mentioned above and those yet to be explained below can be used not only in the respectively indicated combination but also in other combinations or by themselves without leaving the scope of the present invention.

Drawings

Preferred exemplary embodiments of the invention are illustrated in the drawings and are described in more detail in the following description.

In the drawings, in each case schematically:

figure 1 shows an example of an electric motor according to the invention in longitudinal section along the axis of rotation of the rotor,

figure 2 shows the stator of the electric motor according to figure 1 in a cross-section perpendicular to the axis of rotation of the rotor,

figure 3 shows a detail of the stator of figure 2 in the region of a gap between two circumferentially adjacent stator teeth,

fig. 4 shows a variant of the electric motor of fig. 1, in which the coolant flowing through the cooling channels also serves to cool the shaft bearings of the rotor,

fig. 5 to 9 show further different construction variants of the gap between two stator teeth filled with a plastic composition.

Detailed Description

Fig. 1 shows examples of an electric motor 1 according to the invention in a sectional view, the electric motor 1 being dimensioned such that it can be used in a vehicle, preferably in a road vehicle.

The electric motor 1 comprises a rotor 3 and a stator 2, said rotor 3 being illustrated in fig. 1 only in a rough schematic way. For illustration, in a separate illustration, fig. 2 shows the stator 2 in a cross-section perpendicular to the axis of rotation D along the section line II-II of fig. 1. According to fig. 1, the rotor 3 has a rotor shaft 31 and can have a plurality of magnets, not shown in more detail in fig. 1, whose magnetic poles alternate in the circumferential direction U. The rotor 3 is rotatable about a rotational axis D, the position of which is determined by the central longitudinal axis M of the rotor shaft 31. The rotation axis D defines an axial direction a extending parallel to the rotation axis D. The radial direction R is perpendicular to the axial direction a. The circumferential direction U rotates about the rotation axis D.

As can be seen from fig. 1, the rotor 3 is arranged in the stator 2, the electric motor 1 shown here therefore being a so-called inner rotor, however, an implementation is also conceivable as a so-called outer rotor, in which the rotor 3 is arranged outside the stator 2, on the stator 2 the rotor shaft 31 is mounted rotatably about the axis of rotation D in an -th shaft bearing 32a and in a second shaft bearing 32b which is axially distanced from the -th shaft bearing 32 a.

In a known manner, the stator 2 additionally comprises a plurality of stator windings 6, which plurality of stator windings 6 is electrically excited for the purpose of generating a magnetic field. The magnetic interaction between the magnetic field generated by the magnets of the rotor 3 and the magnetic field generated by the stator windings 6 causes the rotor 3 to rotate.

The cross section in fig. 2 reveals that the stator 2 can have a ring-shaped stator body 7, e.g. consisting of iron, in particular the stator body 7 can be formed by a plurality of stator body plates (not shown) which are stacked on top of another in the axial direction a and are adhered to each other a plurality of stator teeth 8 are formed radially on the inside on the stator body 7, which extend in the axial direction a, project radially inwards away from the stator body 7 and are arranged at a distance from each other in the circumferential direction U, each stator tooth 8 carries a stator winding 6. each stator winding 6 forms a winding arrangement, each stator winding 6 of the entire stator winding arrangement can be electrically wound up at correspondingly depending on the number of poles to be formed by the stator windings 6.

During operation of the electric motor 1, the electrically excited stator windings 6 generate waste heat which needs to be dissipated from the electric motor 1 in order to prevent overheating and associated damage or even destruction of the electric motor 1. The stator windings 6 are thus cooled with the aid of the coolant K which passes through the stator 2 and absorbs the waste heat generated by the stator windings 6 by heat transfer.

In order to pass the coolant K through the stator 2, the electric motor 1 comprises a coolant distribution chamber 4 into which the coolant K can be introduced via a coolant inlet 33. along the axial direction a, a coolant collection chamber 5 is arranged at a distance from the coolant distribution chamber 4. the coolant distribution chamber 4 is in fluid communication with the coolant collection chamber 5 via a plurality of cooling channels 10, of which only a single cooling channels can be discerned in the illustration of fig. 1. in a cross section perpendicular to the axial direction a, which is not shown in the figures, the coolant distribution chamber 4 and the coolant collection chamber 5 can each have an annular geometry.along the circumferential direction U, a plurality of cooling channels 10 are arranged at a distance from one another, which extend in each case in the axial direction a from the annular coolant distribution chamber 4 to the annular coolant collection chamber 5. the coolant K introduced into the coolant distribution chamber 4 via the coolant inlet 33 can thus be distributed between the individual cooling channels 10. after the flow-through the cooling channels 10 and heat absorbed from the stator, the coolant K is collected in the coolant distribution chamber 4 and is again conducted out of the stator via the coolant outlet 34.

As is revealed by the illustration in fig. 1 and 2, the stator windings 6 are arranged in the gaps 9 which are realized in each case between two stator teeth 8 which are adjacent in the circumferential direction U. Said interspace 9 is also known to the person skilled in the relevant art as a so-called "stator slot" or "stator slit" extending in the axial direction a like the stator teeth 8.

It should now be noted from the illustration of fig. 3, fig. 3 shows a detailed illustration of the gap 9 which is realized between two adjacent stator teeth 8 (also referred to below as stator teeth 8a, 8b) in the circumferential direction U, in order to improve the heat transfer of the waste heat generated by the stator winding 6 to the coolant K flowing through the cooling channel 10, according to fig. 3, a plastic composition 11 consisting of plastic is provided in the gap 9 in each case, it is particularly preferred that the plastic composition 11 is an injection-molded composition consisting of electrically insulating plastic, the application of the injection-molding method simplifies and speeds up the production of the plastic composition, in the example of fig. 3, the plastic composition 11 consists of a single plastic material, the cooling channel 10 arranged in the gap 9 and the stator winding 6 arranged in the same gap 9 are incorporated into the plastic composition 11, the plastic composition 11 being able to consist of, for example, of thermosetting plastic or thermoplastic, it being self-evident that the stator winding 6 arranged in the gap 9 according to fig. 3 is in each case illustrated with the second tooth 24 a, a stator winding 866 b, which is carried in the stator winding 12, which is carried in the stator winding 6a portion 368 b, which is carried in the circumferential direction U, which is carried by a second stator tooth, a stator winding 12, which is carried in the stator winding 6b, which is illustrated in fig. 3, which is carried in the stator winding 6a 3, which is carried in the stator winding 6b, which is carried in the stator winding 6a stator winding 6, which is carried in the stator winding 6, which is.

As further revealed by in the detailed illustration in fig. 3, an additional electrical insulation 15 consisting of an electrically insulating material is arranged in the respective interspace 9 between the plastic compound 11 and the stator body 7 or the two stator teeth 8a, 8b defining the interspace 9 in the circumferential direction U. an electrical insulation 15 consisting of paper proves particularly cost-effective in this way, in the event that the plastic compound 11 breaks due to a thermal overload or is damaged in or some other way, an undesired electrical short circuit of the stator winding 6 with the material of the stator body 7 or the stator teeth 8 or 8a, 8b (typically iron or or some other suitable electrically conductive material) can be avoided.

As illustrated in the detailed representation in fig. 3, the cooling channels 10 can in each case be formed from a tube body 16 (for example composed of aluminum) which surrounds a tube body interior 22, alternatively, as illustrated in the detailed representation in fig. 3, or more partition elements 18 can be formed on the tube body 16, which partition elements subdivide the cooling channels 10 into partial cooling channels 19 which are fluidically separated from one another, in this way the flow behavior of the coolant K in the cooling channels 10 can be improved, which is associated with an improved heat transfer to the coolant K, furthermore, the tube body 16 is additionally mechanically reinforced in this way, three such partition elements 18 are illustrated by way of example in fig. 3, thus resulting in four partial cooling channels 19, of course in a variant of the example, a different number of partition elements 18 is possible, the tube body 16 forming the cooling channels 10 is realized as a flat tube 17, which flat tube 17 has, in a cross section perpendicular to the axis D of the rotor 3, two wide sides 20 and two narrow sides 21 (see fig. 3), the axial direction of the flat tube 70, the flat tube length of which is at least four times as long as the length of the flat tube 20, preferably as the two flat tubes extending perpendicular to the axial direction R.

In the example of fig. 1 to 3, the cooling channels 10 are arranged in the respective interspaces 9 radially outside the stator winding 6. The radial distance between the cooling channels 10 and the axis of rotation D of the rotor 3 is thus greater than the distance between the stator windings 6 and the axis of rotation D. However, an arrangement of the cooling channels 10 radially inside is also conceivable.

In the following, reference is made again to fig. 1, as illustrated illustratively by fig. 1, the plastic composition 11 realized in the manner of an body can project axially from the interspace 9 on both sides, alternatively or additionally, this also allows the coolant distribution chamber 4 and the coolant collection chamber 5 to be incorporated into the plastic composition 11 for the purpose of being thermally coupled with the axial ends 14a, 14b of the respective stator winding 6 arranged axially outside the respective interspace 9, in other words, in the case of this embodiment variant, plastic compositions 11 define the coolant distribution chamber 4 and the coolant collection chamber 5 at least in part in each case.

In this way, an efficient heat transfer to the coolant K present in the coolant distribution chamber 4 and/or the coolant collection chamber 5 can take place even in the region of the axial ends 14a, 14b of the stator winding 6 concerned, which are usually subjected in particular to thermal loads. This measure allows a particularly effective cooling of the two axial ends 14a, 14b of the stator winding 6.

Further, according to fig. 1, the stator 2 with the stator body 7 and the stator teeth 8 is arranged axially between the th and second end dust caps 25a, 25b as revealed by fig. 1, the part of the coolant distribution chamber 4 is arranged in the th end dust cap 25a and the part of the coolant collection chamber 5 is arranged in the second end dust cap 25b the coolant distribution chamber 4 is thus defined by both the th end dust cap 25a and by the plastic composition 11 the coolant collection chamber 5 is defined by both the second end dust cap 25b and by the plastic composition 11 accordingly.

The coolant distribution chamber 4 and the coolant collection chamber 5 are in each case partly formed by cavities 41a, 41b provided in the plastic compound 11, the th cavity 41a is complemented by a cavity 42a realized in the th end dust cap 25a to form the coolant distribution chamber 4, correspondingly, the second cavity 41b is complemented by a cavity 42b realized in the second end dust cap 25b to form the coolant collection chamber 5.

Furthermore, the coolant supply device 35 can be implemented in the -th end dust cover 25a and fluidly connects the coolant distribution chamber 4 to the coolant inlet 33 provided on the outside (as shown in fig. 1, in particular on the circumferential side of the -th end dust cover 25 a.) correspondingly, the coolant discharge device 36 can be implemented in the second end dust cover 25b and fluidly connects the coolant collection chamber 5 to the coolant outlet 34 provided on the outside (as shown in fig. 1, in particular on the circumferential side of the second end dust cover 25 b.) this enables, in each case, an arrangement of the coolant distribution chamber 4 and/or the coolant collection chamber 5 radially outside the -and/or second end 14a, 14b of the stator winding 6 concerned and in the extension of said end 14a, 14b in the axial direction a. the end 14a, 14b of the stator winding 6, which is subjected to thermal loading in particular during operation of the electric motor 1, can be cooled particularly effectively in this way.

According to fig. 3, the interspace 9 comprises an -th subspace 9c, in which the stator winding 6 is arranged, and a second subspace 9d, in which the cooling channel 10 is arranged and which is complementary to the -th subspace 9c to form the interspace 9, as is revealed by fig. 3 and 4, a positioning device 27 can be arranged between the two subspaces, by means of which the cooling channel 10 is positioned in the second subspace 9d, said positioning device 27 comprising two projections 28a, 28b realized on two stator teeth 8a, 8b which are adjacent in the circumferential direction U and define the interspace 9, the two projections 28a, 28b facing each other in the circumferential direction U and projecting into the interspace for the purpose of positioning the cooling channel, the projections 28a, 28b serve as radial stops for preventing an undesired radially inward movement of the cooling channel 10, in particular during the manufacture of the plastic composition 11 or by injection molding, for the cooling channel 10 realized as a tube body 16 or a flat tube 17.

According to fig. 1, the plastic compound 11 consisting of electrically insulating plastic can also be arranged on the outer circumferential side 30 of the stator body 7 and a plastic coating 11.1 can be formed on the outer circumferential side 30. The stator body 7 of the stator 2, which is usually formed by electrically conductive stator plates, can thus be electrically insulated from the surroundings. The provision of a separate housing accommodating the stator body 7 can thus be eliminated.

To produce the electric motor 1 according to fig. 1 to 3, an electrical insulating element 15, for example made of paper, is first inserted into the recess 9. Thereafter, the stator winding 6 is introduced into the interspace 9 and encapsulated by injection molding using a plastic (for example a thermosetting plastic) from which the plastic composition 11 is made. The perforations 40 forming the cooling channels 2 are then introduced into the plastic composition 11 with the aid of a suitable drilling tool. In the manufacturing process of the plastic composition 11, the stator body 7 can also be encapsulated by injection molding using the plastic from which the plastic composition 11 is made (that is, in particular, using a thermosetting plastic). The coolant distribution chamber 4 and the coolant collection chamber 5 are likewise produced during the injection molding process.

Fig. 4 shows a variation of the example of fig. 1 in a longitudinal section along the axis of rotation D of the rotor 3, likewise for cooling the rotor shaft 31 and the two shaft bearings 32a, 32b during operation of the electric motor 1, the coolant supply device 35 can be thermally coupled to the shaft bearing 32a arranged in the end dust cover 25a, likewise, the coolant discharge device 36 can be thermally coupled to the second shaft bearing 32b arranged in the second end dust cover 25b, in this way separate cooling devices for cooling the shaft bearings 32a, 32b can be excluded, which leads to a cost advantage, in the example of fig. 4, the coolant inlet 33 and the coolant outlet 34 are provided in the respective outer end sides 26a and 26b of the and the second end dust covers 25a, 25b, respectively, in the case of the variation according to fig. 4 and 1, the stator winding 6 is arranged radially in the cooling channel 10 with respect to the radial direction R, the stator winding 6 is led out of the stator 20 through the second end dust cover 25b by means of electrical connections 59, so that the coolant is distributed from the stator winding 39 and the coolant chamber 39 is arranged radially outside the cooling chamber or cooling chamber with respect to the axis of rotation D5.

Fig. 5 shows a development of the example of fig. 3. The development in fig. 5 differs from the example in fig. 3 in that the cooling channels 10 are arranged not only radially on the outside but also radially on the inside in the intermediate space 9, which cooling channels 10, like the example in fig. 3, can be realized as tube bodies 16 or flat tubes 17. By way of example, the radially inner cooling channel 10 is illustrated as a flat tube 17 with two dividing elements 18 and three partial cooling channels 19. To the extent important and flexible, the above description of the example of fig. 3 applies equally to the example of fig. 5.

Attention should now be directed to the illustration of fig. 6, which shows a detailed illustration of the gap 9 realized between two stator teeth 8 adjacent in the circumferential direction U, which are also referred to below as stator teeth 8a, 8 b. In order to improve the heat transfer of the waste heat generated by the stator windings 6 to the coolant K flowing through the cooling channels 10, according to fig. 6, a plastic compound 11 consisting of plastic is provided in each case in the interspace 9. The cooling channels 10 arranged in the interspaces 9 and the stator windings 6 arranged in the same interspaces 9 are incorporated into a plastic compound 11, which plastic compound 11 can consist of or comprise a thermosetting plastic, for example. In the example of fig. 6, a plastic compound 11 consisting of a single plastic material is arranged in the interspace 9.

It goes without saying that the stator winding 6 arranged in the air gap 9 according to fig. 6 is in each case partially associated with the th stator winding 6a carried by the th stator tooth 8a and partially assigned to the second stator winding 6b, which second stator winding 6b is carried by the second stator tooth 8b adjacent to the th stator tooth 8a in the circumferential direction U, for the sake of perceiving this, in fig. 6a possible virtual partition line 12 is depicted in a similar manner to fig. 3, the stator winding 13a shown to the left of the partition line 12 in fig. 6 belongs to the stator winding 6a carried on the stator tooth 8a, the stator winding 13b shown to the right of the partition line 12 thus belongs to the stator winding 6b carried by the second stator tooth 8 b.

In the example of fig. 6, the cooling channel 10 realized in each interspace 9 is realized by a plurality of perforations 40 provided in the plastic compound 11, through which the coolant K can flow. By way of example in fig. 6 only four such perforations 40 are shown, the perforations 40 being arranged at a distance from one another in the circumferential direction U and extending in each case in the axial direction a. The perforation 40 can be realized as a through hole introduced into the plastic composition 11 by means of a suitable drilling tool. The perforations 40 in the cross section perpendicular to the axis of rotation D can have a rectangular geometry in each case with two broad sides 20 and with two narrow sides 21. The length of the two broad sides 20 is at least twice, preferably at least four times, the length of the two narrow sides 21. Thus mimicking the beneficial geometry of a flat tube.

As further revealed by in the detailed illustration in fig. 3, an electrical insulation 15 consisting of an electrically insulating material is arranged in each space 9 between the plastic compound 11 and the stator body 7 or the two stator teeth 8 defining the gap 9 in the circumferential direction U in this way, in the event that the plastic compound 11 breaks due to a thermal overload or is damaged in or some other way, undesired electrical short-circuits of the affected stator winding 6 and the material of the stator body 7 or the stator teeth 8 or 8a, 8b (typically iron or or some other electrically conductive material) can be avoided, the electrical insulation 15 consisting of paper proves particularly cost-effective.

In the example of fig. 6, the perforations 40 forming the cooling channels 10 are arranged in the plastic compound 11 radially outside the stator winding 6 with respect to the radial direction R. The radial distance between the cooling channels 10 and the axis of rotation D of the rotor 3 is thus greater than the distance between the stator windings 6 and the axis of rotation D. In a cross section perpendicular to the axial direction a shown in fig. 6, the two broad sides 20 of the perforation 40 extend in each case perpendicular to the radial direction R.

Fig. 7 shows a variation of the example of fig. 6. In the case of the electric motor 1 according to fig. 7, the cooling channel 10 is not arranged in the plastic compound 11, but in the stator body 7 of the stator 2. As revealed in fig. 7, the perforations 40 forming the cooling channel 10 are arranged in the stator body 7 radially outside the interspace 9 and between two stator teeth 8a, 8b adjacent with respect to the circumferential direction U. In a similar manner to the example of fig. 6, the cooling channel 10 is formed by a perforation 40 provided in the stator body 7. During the manufacture of the stator body 7, the cooling channels 10 can thus be formed by introducing the perforations 40 into the stator body 7 or into the stator body plates forming the stator body 7, preferably in the form of holes drilled with the aid of a suitable drilling tool.

Fig. 8 shows a variation of the example of fig. 7. Also in the case of the variant according to fig. 8, the perforations 40 forming the cooling channels 10 are arranged in the stator body 7 of the stator 2. In the example of fig. 8, the perforations 40 arranged in the stator body 7 are realized to be open towards the interspace 9. As is revealed in fig. 8, the perforation 40 is closed in a liquid-tight manner towards the interspace 9 and by the plastic composition 11 provided in the interspace 9.

Fig. 9 shows a development of the example of fig. 8, in the case of the electric motor 1 according to fig. 9, the cooling channels 10 are provided both in the stator body 7 and in the plastic compound 11, the cooling channels 10 provided in the stator body 7 (also referred to below as "radially outer cooling ducts" 10a) are realized in a manner similar to the example of fig. 8 and so with reference to the above description in relation to fig. 8, the cooling ducts 10 arranged in the plastic compound 11 are also referred to below as "radially inner cooling ducts" 10b, the stator winding 6 is therefore arranged between the two cooling ducts 10a, 10b with respect to the radial direction R, as shown by the detailed illustration of fig. 9, the radially outer cooling ducts 10b can be formed by a tube body 16 (for example composed of aluminum) surrounding the tube body interior 22, alternatively, as shown in the detailed illustration of fig. 9, or a plurality of dividing elements 18 can be formed on the tube body 16 and dividing the cooling channels 10 into partial cooling channels 19 which are fluidically separated from one another, this can be improved in such a way that the coolant flow in the cooling channels 10 is at least four times as a transverse cross section 20, which is a transverse to the transverse direction of the tube body 16, and this transverse direction of the transverse flow of the cooling channels 18, which is also can be improved by four times the transverse direction of the transverse flow of the transverse direction of the transverse flat tube body 16, which is possible, which is also by two transverse direction of the transverse direction of the transverse direction of the transverse tube body 16, which is as a transverse direction of the.

Within the scope of practice, the above-described variants according to fig. 3 to 9 can be combined with one another.

The plastic compound 11 can also surround the winding parts of the stator windings 6 that protrude axially from the air gap 9 of the stator body and in so doing partially define the coolant distribution chamber 4 and/or the coolant collection chamber 5, so that the associated stator windings 6 or the associated winding parts of the stator windings 6 are electrically insulated from the coolant when the coolant passes through the associated cooling channels 10 during operation of the electric motor 1.

Conveniently, the coolant distribution chamber 4 and the coolant collection chamber 5 are advantageously arranged in the axial extension of the stator body 7 adjacent to the latter. Preferably, the coolant distribution chamber 4 and/or the coolant collection chamber 5 do not protrude beyond the stator body 7 or the stator 2 in its radial direction R.

The stator windings 6 are realized in each case as: so that during operation of the electric motor 1 it is electrically insulated from the coolant K and from the stator body 7 of the stator 2, at least in the region within the respective interspace 9. During operation of the electric motor 1, undesirable electrical short-circuiting of the stator windings 6 with the stator body 7 is prevented in this way by the coolant K. Conveniently, such electrical insulation of the stator winding 6 with respect to the stator body 7 (preferably also with respect to the stator teeth 8 defining the interspace 9) is formed entirely by the plastic composition 11 and/or by the additional electrical insulation 15 already described above.

Conveniently, the additional electrical insulation 15 extends within the gap 9 over the entire length of the gap 9 measured along the axial direction a, such that it insulates the stator winding 6 from the stator body 7 and/or the stator teeth 8. Within the interspace 9, at least over the entire length of the interspace 9 along its circumferential boundary, an additional electrical insulation 15 likewise expediently surrounds the stator winding 6. Conveniently, the stator winding 6 is also electrically insulated from the cooling channel realized as a tube 16. In this case, the electrical insulation is formed by the plastic compound and, alternatively or additionally, the additional electrical insulation 15.