Electric machine

Abstract

An electrical machine (1) comprising a stator (2) with a plurality of stator slots (4) arranged in a stator base body (3) distributed in the circumferential direction, wherein a plurality of conductor elements (5) are arranged within the stator slots (4) in different radial positions between an inner, in particular innermost, radial position (6) and an outer, in particular outermost, radial position (7). The electrical machine (1) comprises at least one cover pin (8), in particular a plurality of cover pins (8), which has a conductor element (5) arranged in an inner, in particular innermost, radial position (6) and a conductor element (5) arranged in an outer, in particular outermost, radial position (7). The at least one cover pin (8) has a contacting section (9) arranged between the conductor elements (5) of the cover pin (8) and extending at least in sections parallel to an axial end face (11) of the stator base body (3).which contacting section (9) has a non-linear shape.,

Description

The invention relates to an electric machine comprising a stator having a plurality of stator grooves arranged distributed in the circumferential direction in a stator base body, wherein a plurality of conductor elements are arranged within the stator grooves in different radial positions between an innermost radial position and an outermost radial position, wherein the electric machine comprises at least one covering pin, in particular a plurality of covering pins, which has a conductor element arranged on an inner, in particular innermost, radial position and a conductor element arranged on an outer, in particular outermost, radial position.Electric machines of the type mentioned at the beginning are fundamentally known from the prior art, wherein, in addition to concentrated windings of conductor elements, electric machines with a so-called "distributed winding" are also known. Distributed windings are generally produced by means of pins, in particular of the so-called "hairpin technology", in which a plurality of conductor elements of pins (hair pins) are inserted into slots of a coil body or stator base body and are connected to form corresponding winding strands. A distributed winding thus comprises at least one winding phase formed from a plurality of pins, but generally a plurality of winding phases. The pins each have axially running conductor elements in the form of limbs or slot sections which are arranged in slots of the coil body in different winding layers in the radial direction.A winding strand has at each of its two ends a connection region which is formed by one end of a respective connection pin and protrudes axially beyond the coil body. A distributed winding end refers to an axial end portion of the coil windings in an electric machine. It is the part at which the connecting wires or lines or the conductor elements of the pins are brought together in order to produce a common electrical connection. The conductor elements usually have a linear shape. Specifically at regions at which they are deformed, in particular in order to connect the different conductor elements extending in the axial direction to one another in the region of the axial end face of the stator base body or of the winding head, the conductor elements or the pins, in particular the covering pins, which connect a radially inner layer, in particular the radially innermost layer, to a charge located radially outer in comparison thereto, in particular the radially outermost layer, are under mechanical tension. If the cover pins are to be contacted by a temperature sensor for a temperature detection, this can lead to a deformation due to the mechanical tension, so that the temperature sensor does not lie flat against the cover pin, but a line contact forms, which can impair the temperature detection.The object of the invention is to specify an electrical machine which is improved in comparison with it.The object is achieved by an electric machine having the features of claim 1. Advantageous embodiments are the subject matter of the dependent claims.As described, the invention relates to an electric machine, for example an electric machine for a motor vehicle. The electric machine can be designed in particular as a traction drive, in particular as an electric drive axle, of the motor vehicle. The electric machine has a stator with a stator base body which provides a plurality of stator grooves which are arranged distributed in the circumferential direction with respect to a rotational axis of the electric machine or of a rotor of the electric machine and which receive the conductor elements of the pins. Therefore, a plurality of conductor elements of different pins are accommodated within the stator slots, which conductor elements are adjacent to one another in the radial direction within a stator slot. The at least one cover pin has two conductor elements, wherein one conductor element, for example a first conductor element, is arranged at an inner, in particular innermost, radial position of a first stator slot and another conductor element, for example a second conductor element, is arranged at an outer, in particular outermost, radial position of a second stator slot. In other words, the conductor elements can be understood as legs of the cover pin which extend in different stator grooves, namely a conductor element on the inner, in particular innermost, radial position and a conductor element on the outer, in particular outermost, radial position of different stator grooves.The invention is based on the finding that the at least one cover pin has a contacting section which runs at least in sections parallel to an axial end face of the stator base body and is arranged between the conductor elements of the cover pin, which contacting section has a non-linear shape. In other words, the contacting section of the cover pin connects the two conductor elements of the cover pin. The cover pin can thus be divided at least functionally into the conductor elements and the contacting section, wherein the cover pin can, however, be embodied in one piece or in one piece. The contacting section is thus arranged outside the stator grooves in the region of the winding head or in the region of the axial end face of the stator base body. At least a part of the contacting section extends parallel to the axial end face of the stator base body and establishes the connection between the conductor element on the inner, in particular innermost, radial position and the conductor element on the outer, in particular outermost, radial position.The non-linear shape of the contacting section ensures that a defined contacting with the at least one temperature sensor is possible. Compared to a linear configuration of the contacting section, i.e. a straight guidance of the contacting section from the conductor element arranged at the inner, in particular innermost, radial position to the conductor element arranged at the outer radial position, the non-linear shape offers advantages with regard to contacting and stability, in particular in such a way that a line contact, which could otherwise occur in particular as a result of tilting of the contact section, is prevented and a flat contact is ensured.In one embodiment of the electric machine, it can be provided that the contacting section has at least one geometry that increases the stability and / or a contact surface. In particular, the stability and / or the contact surface is increased by the non-linear shape of the contacting section compared to a linear shape of the contacting section. For example, a shape deviating from the linear shape increases stability against twisting or deformation of the contacting section. The bearing surface is likewise increased, at which the contacting section can be contacted by a temperature sensor, since the path length of the contacting section extends compared to a straight configuration of the contacting section, in particular compared to a straight connection of the inner, in particular innermost, and outer, in particular outermost, radial positions. The contact surface is also increased because no rotation of the contacting section is provided, so that a line contact is prevented and a flat contact can be ensured.According to a further embodiment, the contacting section can provide a support surface arranged parallel to an axial end surface. By means of the proposed embodiment of the contacting section, the bearing surface provided by the contacting section is aligned parallel to the axial end face of the stator base body, in particular for contacting by a temperature sensor, and the alignment is ensured. In other words, during operation, the shape of the contacting section ensures that the bearing surface remains aligned parallel to the axial end face of the stator base body and does not deviate from this alignment due to a deformation of the cover pin, in particular of the contacting section. This allows in particular a physical contacting by the temperature sensor, forming a surface contact.As described at the beginning, the contacting section is nonlinearly shaped. The non-linear configuration means in particular that the contacting section does not extend straight, but deviates from a straight guide within the electric machine. According to one configuration, the contacting section can have at least one curvature. The contacting section is thus curved at least in one direction and therefore not straight. The curvature can in principle be chosen as desired, wherein in particular curvatures in both directions in the circumferential direction are possible. The curvature extends in particular in a plane perpendicular to the axis of rotation.In particular, the contacting section can be S-shaped and / or wave-shaped. The curvature can thus be opposite in different subsections, so that a first curvature section can be formed with a first direction of curvature and a second curvature section adjoining it with an opposite direction of curvature. The contacting section can likewise be designed in a wave-shaped manner, wherein the number of blows or bends can be selected as desired, for example more than three blows or bends or curvatures.According to a further embodiment, the electric machine can have exactly one described cover pin, i.e. a cover pin providing a described contacting section and / or a plurality of cover pins distributed in the circumferential direction and / or a plurality of cover pins arranged in a circle segment of the electric machine. For example, the described cover pin can be provided for contacting an individual temperature sensor. In this case, it is sufficient that the electric machine provides exactly one cover pin which has a contacting section as described. It is also possible for all cover pins, i.e. all pins which have conductor elements on inner, in particular innermost, and outer, in particular outermost, radial positions, to have a correspondingly shaped contacting section. In the context of the application, a "cover pin" is thus generally understood to mean a pin with a contacting section which engages around other conductor elements arranged between the limbs or the conductor elements of the cover pin in the radial direction and / or in the circumferential direction. The legs or conductor elements of the cover pin can be arranged on inner and outer radial positions, wherein these do not necessarily have to be the innermost and outermost radial positions, but can be arranged there. Furthermore, a segment of a circle of the electric machine can be defined, in which the described cover pins have the contacting section.As described, the electric machine can have a temperature detection device. According to one embodiment, the electric machine can have a temperature detection device which is designed to detect a temperature of the electric machine, wherein the temperature detection device has at least one temperature sensor which is thermally coupled to the at least one contacting section. By the above-described embodiment of the contacting section, in particular parallel to the axial end face of the stator base body, a support surface for the temperature sensor is ultimately provided, which also runs parallel to the axial end face of the stator base body. In other words, the temperature sensor can be installed or arranged in an axially parallel manner with respect to the axis of rotation of the electric machine, for example in a housing of the electric machine and thus physically contact the contacting section in order to be in thermal contact with the contacting section. The defined bearing of the temperature sensor on the contacting section, in particular the surface contact, ensures a defined temperature detection.The at least one cover pin can engage with the contacting section around a plurality of conductor elements arranged in the radial direction between the inner, in particular innermost, radial position and the outer, in particular outermost, radial position. As already described at the beginning, a plurality of conductor elements of different pins are accommodated in the stator slots, wherein the cover pin described has conductor elements, of which one conductor element is arranged at the inner, in particular innermost, radial position of a stator slot and the other conductor element is arranged at the outer, in particular outermost, radial position of another stator slot. The contacting section, which connects the two conductor elements of the cover pin, encompasses in the radial direction conductor elements which are arranged on radial positions which are located between the inner, in particular innermost, radial position and the outer, in particular outermost, radial position, in other words the contacting section forms an "arc" or a "roof" which encompasses the conventional pins or "hair pins".In addition to the electric machine, the invention relates to a motor vehicle which comprises an electric machine described above. The invention further relates to a method for producing an electric machine, comprising a stator having a plurality of stator grooves arranged distributed in the circumferential direction in a stator base body, wherein a plurality of conductor elements are arranged within the stator grooves in different radial positions between an inner, in particular innermost, radial position and an outer, in particular outermost, radial position, wherein the electric machine comprises at least one cover pin, in particular a plurality of cover pins, which has a conductor element arranged on an inner, in particular innermost, radial position and a conductor element arranged on an outer, in particular outermost, radial position, wherein the at least one cover pin is formed with a contacting section, which runs at least in sections parallel to an axial end face of the stator base body and is arranged between the conductor elements of the cover pin, which contacting section has a non-linear shape.The method can be carried out in particular for producing the above-described electric machine. The motor vehicle has the electric machine in particular as a drive device, in particular as a traction drive or as an electric drive axle. All advantages, details and features described with respect to the electric machine can be completely transferred to the motor vehicle and the method.The invention is explained below on the basis of exemplary embodiments with reference to the figures. The figures are schematic representations and show: FIG. 1 shows a schematic illustration of a detail of an electric machine according to a first exemplary embodiment; FIG. 2 shows a schematic illustration of a detail of an electric machine according to a second exemplary embodiment; FIG. 3 shows a schematic illustration of a cover pin for an electric machine according to FIGS. 1, 2; FIG. 4 shows a schematic illustration of a cover pin for an electric machine according to FIGS. 1, 2; FIG. 5 shows a schematic illustration of a cover pin for an electric machine according to FIGS. 1, 2; and FIG. 6 shows a schematic illustration of a cover pin for an electric machine according to FIGS. 1, 2.FIG. 1 shows an electric machine 1, which forms, for example, a component of a motor vehicle, not shown in detail, in particular as its drive device or traction drive, in particular as an electric drive axle. The electric machine 1 has a stator 2 with a stator base body 3 which comprises a multiplicity of stator grooves 4 which are arranged in the stator base body 3 in the circumferential direction with respect to a rotational axis of the electric machine 1. In each of the stator slots 4, a plurality of conductor elements 5 of different pins or hair pins are arranged, which are arranged next to one another in different radial positions between an inner, in particular innermost, radial position 6 and an outer, in particular outermost, radial position 7.The electric machine 1 has a plurality of covering pins 8 which have corresponding conductor elements 5, of which a conductor element 5 extends in an inner, in particular innermost, radial position 6 and a conductor element 5 extends in an outer, in particular outermost, radial position 7 of different stator slots 4. A corresponding cover pin 8 is shown in isolation in FIGS. 3-6. In FIG. 1, exactly one cover pin 8, for example according to FIG. 3, has a contacting section 9, which connects the two conductor elements 5 to one another, wherein the contacting section 9 has a non-linear shape. In FIG. 2, it is shown in a different manner that all cover pins 8, i.e. those pins of the electric machine 1 which have conductor elements 5 in the inner, in particular innermost, radial positions 6 and outer, in particular outermost, radial positions 7, have such a nonlinear contacting section 9. It is likewise possible for any other number and / or grouping of cover pins 8 to be provided with such contact sections 9 or for these to be arranged in groups or in circle segments of the electric machine 1. The description can be accordingly transferred.The non-linear shape of the contacting section 9 increases the stability of the contacting section 9 compared to a linear embodiment and at the same time the contact surface for a temperature sensor 10, as described below with reference to FIGS. 4-6, is increased or the contact surface is generally improved.FIG. 3 shows, by way of example, that the contacting section 9 is curved. The contacting section 9 has in particular a wave-shaped curvature or an S-shaped curvature, so that oppositely curved sections adjoin one another in the contacting section 9. As a result, the resistance of the contacting section 9 to rotation or deformation is increased, so that the contacting section 9 provides a support surface 12 which runs parallel to an axial end surface 11 of the stator base body 3 and which remains ensured that the support surface 9 does not change during operation or does not deviate from the parallel alignment.As can also be seen from FIGS. 1, 2, the cover pin 8 with the contacting section 9 engages around a plurality of conductor elements 5 of other pins or hair pins, between the inner, in particular innermost, radial position 6 and the outer, in particular outermost, radial position 7. The cover pins 8 have conductor elements 5, of which one conductor element 5 is arranged at an inner, in particular innermost, radial position 6 of a stator slot 4 and the other conductor element 5 is arranged at the outer, in particular outermost, radial position 7 of another stator slot 4. Accordingly, the intermediate conductor elements 5 of other pins, which are located between the inner, in particular innermost, radial position 6 and the outer, in particular outermost, radial position 7 of the intermediate stator grooves 4, are surrounded in the radial direction by the contacting section 9. The contacting section 9 therefore forms a type of "roof" in the axial direction, which extends over the corresponding conductor elements 5.FIG. 4 shows that the contact-making section 9 is contacted by the temperature sensor 10, in particular on the contact surface 12. Due to the non-linear shape of the contacting section 9, the contacting section 9 is prevented from deforming, in particular twisting. As a result, the planar contact between the contact surface 12 and the contact surface of the temperature sensor 10 is maintained. FIG. 5 shows a perspective illustration that the support surface 12 has an increased length as a result of the multiple curved shape compared to a straight configuration, with the result that overall the effective support surface 12 between the contacting section 9 and the temperature sensor 10 increases. Furthermore, due to the stabilizing effect of the contacting section 9, the surface contact is ensured and line contact is prevented.FIG. 6 shows a perspective illustration below the temperature sensor 10. It can be seen that the cross-sectional area of the cover pin 8 is not necessarily changed, but rather its shape is specifically deformed, for example by mechanical deformation or by a forming process, during the production of the cover pin 8, such that it is more resistant to deformations and thus provides a defined bearing surface 12 for the temperature sensor 10, namely at the contacting section 9.The support surface 12 can extend in particular parallel to the axial end surface 11 of the stator base body 3, so that the temperature sensor 10 can be installed in the electric machine 1 in an axially parallel manner and a defined mechanical contact between the temperature sensor 10 and the contacting section 9, namely on the support surface 12, is ensured, which ensures a defined temperature input into the temperature sensor 10, so that the temperature of the electric machine 1, in particular of the stator 2, can be detected at the cover pin 8, namely at the contacting section 9, in a defined manner.The advantages, details and features shown in the individual exemplary embodiments can be combined with one another, transferred to one another and interchanged. The method for producing an electric machine described herein can be used to produce the electric machine 1 shown. As described, electric machine 1 may be part of a motor vehicle, not shown in detail. All the advantages, details and features shown can therefore also be transferred to the motor vehicle and the method.Reference numerals denote reference numerals1 Electric machine 2 Stator 3 Stator base body 4 Stator groove 5 Conductor element 6 Innermost radial position 7 Outermost radial position 8 Covering pin 9 Contacting section 10 Temperature sensor 11 End face 12 Bearing surface

Claims

Electric machine (1) comprising a stator (2) having a multiplicity of stator grooves (4) arranged distributed in the circumferential direction in a stator base body (3), wherein a plurality of conductor elements (5) are arranged within the stator grooves (4) in different radial positions between an inner, in particular innermost, radial position (6) and an outer, in particular outermost, radial position (7), wherein the electric machine (1) comprises at least one covering pin (8), in particular a multiplicity of covering pins (8), which has a conductor element (5) arranged on an inner, in particular innermost, radial position (6) and a conductor element (5) arranged on an outer, in particular outermost, radial position (7), characterized in that, the at least one cover pin (8) has a contacting section (9) which runs at least in sections parallel to an axial end face (11) of the stator base body (3) and is arranged between the conductor elements (5) of the cover pin (8), which contacting section (9) has a non-linear shape.Electric machine (1) according to Claim 1, characterized in that the contact-making section (9) has at least one geometry which increases the stability and / or a bearing surface.Electric machine (1) according to Claim 1 or 2, characterized in that the contact-making section (9) provides a bearing surface (12) arranged parallel to an axial end face (11).Electric machine (1) according to one of the preceding claims, characterized in that the contact-making section (9) has at least one curvature.Electric machine (1) according to one of the preceding claims, characterized in that the contacting section (9) is S-shaped and / or wavy.Electric machine (1) according to one of the preceding claims, characterized in that the electric machine (1) has exactly one cover pin (8) and / or a plurality of cover pins (8) distributed in the circumferential direction and / or a plurality of cover pins (8) arranged in a circle segment of the electric machine (1).Electric machine (1) according to one of the preceding claims, characterized bya temperature detection device which is designed to detect a temperature of the electric machine (1), wherein the temperature detection device has at least one temperature sensor (10) which is thermally coupled to the at least one contact-making section (9).Electric machine (1) according to one of the preceding claims, characterized in that the at least one covering pin (8) with the contacting section (9) surrounds a plurality of conductor elements (5) arranged in the radial direction between the inner, in particular innermost, radial position (6) and the outer, in particular outermost, radial position (7).Motor vehicle comprising an electric machine (1) according to one of the preceding claims.Method for producing an electric machine (1), comprising a stator (2) having a multiplicity of stator grooves (4) arranged distributed in the circumferential direction in a stator base body (3), wherein a plurality of conductor elements (5) are arranged within the stator grooves (4) in different radial positions between an inner, in particular innermost, radial position (6) and an outer, in particular outermost, radial position (7), wherein the electric machine (1) comprises at least one covering pin (8), in particular a multiplicity of covering pins (8), which has a conductor element (5) arranged on an inner, in particular innermost, radial position (6) and a conductor element (5) arranged on an outer, in particular outermost, radial position (7), characterized in that, the at least one cover pin (8) is formed with a contacting section (9) which runs at least in sections parallel to an axial end face (11) of the stator base body (3) and is arranged between the conductor elements (5) of the cover pin (8), which contacting section (9) has a non-linear shape.

Images