Stator of an electric machine and electric machine as well as interconnection device

Abstract

comprising stator (34) of an electric machine (8), in particular an electric motor of a motor vehicle - a stator laminated core (36) which has a number of stator teeth (38) and is provided with a rotating field winding (40) comprising several phases arranged on the stator teeth (38), wherein the phases of the rotating field winding (40) are formed from a continuously wound winding wire (42), - and a connection device (44) with a number of U-shaped plug pockets (50) corresponding to the number of phases for receiving one insulation displacement contact (52) each as a connection point of the winding wire (42) with phase connections on a stator end face, wherein each plug pocket (50) has two vertical U-legs (50b, 50c) and a contact slot (56) arranged between them for receiving the winding wire (42), characterized in that one of the two vertical U-legs (50c) of the plug pocket (50) is longer along an axial direction (A) than the other vertical U-leg (50b).

Description

[0001] The invention relates to a stator of an electrical machine, in particular for a motor vehicle, comprising a stator laminated core which has a number of stator teeth and is provided with a rotating field winding arranged on the stator teeth and comprising a plurality of phases, wherein the phases of the rotating field winding are formed from a continuously wound winding wire, and a wiring device with a number of U-shaped plug-in pockets corresponding to the number of phases, each for receiving an insulation displacement contact as a connection point for the winding wire with phase connections on a stator end face, wherein each plug-in pocket has two vertical U-legs and a contact slot arranged between them for receiving the winding wire. The invention further relates to an electrical machine with such a stator and a wiring device for such a stator.

[0002] A brushless electric motor, in particular an electric (three-phase) machine, comprises a stator with a stator core with a number of stator teeth arranged, for example, in a star shape, which support an electric rotating field winding in the form of individual stator coils, which in turn are wound from an insulating wire. The coils are assigned to individual phases of the machine and are interconnected in a predetermined manner via connecting conductors of a connection device or switching unit.

[0003] In the case of a brushless electric motor as a three-phase AC machine, the stator has three phases and thus, for example, three phase conductors or phase windings, each of which is supplied with electric current in a phase-shifted manner to generate a rotating magnetic field in which a rotor or armature, usually equipped with permanent magnets, rotates. The phase ends of the phase windings are connected to the motor electronics to control the electric motor. The coils of the rotating field winding are connected to one another in a specific way using the phase ends via phase connections. The type of connection is determined by the winding pattern of the rotating field winding, with a star connection or a delta connection of the phase windings being common.

[0004] It is also conceivable for the phases of the rotating field winding to be formed from a common, continuous coil or winding wire. Instead of two phase or coil ends, the individual winding wire is connected to the phase terminals at specific connection points.

[0005] The rotating field winding or the winding wire can be connected using insulation displacement contacts. For this purpose, the section of the winding wire to be contacted is pressed into a sleeve-like plug-in pocket and mechanically secured within the plug-in pocket using a metallic insulation displacement contact (clamp plug). The insulation displacement contact typically has at least one cutting edge that, when inserted into the plug-in pocket, cuts through the insulation of the winding wire's insulation wire in such a way that, when the insulation displacement contact is inserted, one core of the winding wire is electrically conductively coupled to the insulation displacement contact. When assembled, the insulation displacement contacts are connected to the motor electronics via the phase connections to supply current to the phases.

[0006] Particularly with rotating field windings wound from a single, continuous winding wire, the problem arises that the winding tool is typically wider than the clear width of the contact slot. This makes it impossible to easily insert the winding wire into the insertion pocket of the respective insulation displacement contacts without collision. In this case, it is therefore necessary, for example, for the winding tool or winding machine to be equipped with additional holding devices for inserting the winding wire into the insertion pocket. This makes the production of such a one-piece or one-piece rotating field winding comparatively complex and cost-intensive.

[0007] DE 10 2015 217 017 A1 discloses a stator assembly for an electric motor. The stator assembly comprises a stator core with a number of inwardly directed stator teeth, with a rotating field winding comprising several phases arranged on the stator teeth. A guide ring is placed on the end face of the stator core, which surrounds the stator teeth as a coil body for guiding the rotating field winding. A ring cover is placed on the end face of the guide ring, on which the phase ends of the rotating field winding are contacted with each other in such a way that the entire rotating field winding does not project radially beyond the outer circumference of the stator core.

[0008] WO 2016 / 124636 A1 discloses an electric motor comprising a switching unit with a number of contact wires and an annular frame part. The contact wires are arranged to form an interconnection ring for the coil ends of a stator winding, and their wire ends are connected with insulation displacement contacts. The insulation displacement contacts have two insulation displacement legs spaced apart from one another to form an insulation displacement slot for connecting at least two of the wire ends. The frame part of the switching unit has a number of insertion pockets corresponding to the number of insulation displacement contacts.

[0009] DE 20 2010 016 199 U1 discloses an electrical connector for a motor stator, comprising a terminal component that includes a first terminal portion and a second terminal portion connected to the first terminal portion, wherein the first terminal portion comprises a pair of adjacent clamping arms. Each of the clamping arms comprises an arm part having a first end connected to the first end of the arm part of the other of the clamping arms, and a second end opposite the first end and further away from the second terminal portion than the first end, and an elastic piercing part having a connecting end connected to the second end of the arm part and a free end extending obliquely toward and spaced from the first end of the arm part of the other of the clamping arms.

[0010] US 2017 / 0033635 A1 describes a brushless motor having a stator core with a plurality of tooth sections. The motor includes a lower insulating coil connected to a lower surface of the stator core, the lower insulating coil having a plurality of lower slot insulating sections, each corresponding to a respective tooth section. The motor further includes an upper insulating coil connected to an upper surface of the stator core, the upper insulating coil having a plurality of upper slot insulating sections, each corresponding to a respective tooth section, such that the upper slot insulating sections, the tooth sections, and the lower slot insulating sections define a plurality of coil winding sections.

[0011] DE 10 2013 114 688 A1 describes an electric motor with a stator arrangement and a rotor arrangement, which stator arrangement has a winding arrangement with a winding wire and a contacting device for contacting the winding wire.The contacting device has a housing, which housing has a wall with a plug-in surface, a first side surface and a second side surface facing away from the first side surface, which wall has a first receiving opening for receiving a contact element and a second receiving opening for receiving the winding wire, wherein the contact element has a slot in which the winding wire can be at least partially received, wherein the second receiving opening extends in the manner of a groove between the first side surface and the second side surface, wherein a support surface of the second receiving opening is designed to support the winding wire, and wherein the first receiving opening extends through the second receiving opening and transversely to the second receiving opening. A centering prism is designed to center the winding wire.

[0012] The invention is based on the object of providing a particularly suitable stator for an electrical machine. The invention is further based on the object of providing a particularly suitable wiring device for such a stator and a particularly suitable electrical machine with such a stator.

[0013] With regard to the stator, the object is achieved according to the invention with the features of claim 1, with regard to the machine with the features of claim 10, and with regard to the interconnection device with the features of claim 11. Advantageous embodiments and further developments are the subject of the respective subclaims. The advantages and preferred embodiments cited with regard to the stator and / or the machine are also transferable mutatis mutandis to the interconnection device, and vice versa.

[0014] The stator according to the invention is suitable and configured for an electrical machine, in particular for an electric motor of a motor vehicle, preferably for an oil pump of a motor vehicle transmission. For this purpose, the stator comprises a stator core, in particular a stamped core, which has a number of stator teeth, in particular arranged in a star shape, for example, directed radially inward. The stator teeth are provided with a multi-phase rotating field winding, wherein each phase (phase winding) comprises at least one coil or coil winding.

[0015] The phases of the rotating field winding are formed from a continuously wound winding wire. This means that all coils of the rotating field winding are wound from a common, continuous coil, phase, or winding wire. To form such a coil, the winding wire is wound in several turns around a respective stator tooth. The phases of the rotating field winding are thus coupled to one another in one piece, i.e., monolithically. In other words, the phases of the rotating field winding merge seamlessly into one another. The coils of the rotating field winding are thus designed as multiple coils, whose coil winding is applied to several, in particular all, stator teeth.

[0016] The winding wire preferably has an electrically conductive core provided with an insulating sheath (insulation). In other words, the winding wire is designed as an insulated wire, in particular as an insulated copper wire. The winding wire is connected to a connection device for the rotating field winding, i.e., in the assembled state, it is contacted or electrically connected to phase terminals. For this purpose, the connection device has a number of U-shaped plug-in pockets corresponding to the number of phases as connection points for the winding wire to phase terminals on a stator end face. Preferably, the two phase or wire ends of the winding wire are also connected or can be connected to a phase terminal.

[0017] Each insertion pocket has two vertical U-shaped legs with a contact slot arranged between them for accommodating a respective section of the winding wire. Preferably, the winding wire is inserted into the contact slot section by section and then electrically contacted and mechanically secured using the insulation displacement contact.

[0018] According to the invention, one of the two vertical U-legs of the insertion pocket is designed to be longer than the other vertical U-leg along an axial direction of the stator. In other words, the vertical U-legs of the insertion pockets have different lengths from each other along the axial direction.

[0019] To form the phase conductors or coil wires of the rotating field winding, the winding wire is applied to the stator teeth of the stator core, for example, fully automatically using a single-needle or multi-needle process. The extended U-shaped leg acts as an (axially) raised shoulder during the winding process. During winding or laying, the winding wire is guided around the extended U-shaped leg using a winding machine's winding tool and then pulled downward, i.e., axially toward the stator core. This causes the winding wire to slide along the extended U-shaped leg and thus be brought into the desired position within the contact slot.

[0020] In other words, it is thus possible to arrange the winding wire in the contact slot during a winding process without using additional holding devices or the like of the winding machine and / or the interconnection device. This makes it possible to wind the stator with the rotating field winding in a simple manner in one pass, i.e., without interrupting the winding process. This results in a particularly suitable stator which is improved, in particular, with regard to assembly or winding effort. In particular, with the stator according to the invention, it is possible to use comparatively simple winding machines to produce the rotating field winding, thereby simplifying the manufacture of the stator and subsequently reducing manufacturing costs.

[0021] By connecting the continuous winding wire using insulation displacement contacts that can be inserted into the plug-in pockets, the wiring of the rotating field winding and thus the stator is significantly simplified. In particular, the contacting of the coils or phases is simplified, as no additional stripping step is required for the insulated winding wire during assembly and wiring. This enables a solder-free connection and electrical contact between the winding wire and the respective assigned phase connection with minimal tooling. This subsequently translates to a reduction in assembly effort during the stator assembly, which further reduces its manufacturing costs. Furthermore, simple and cost-effective contacting and fixing of the winding wire is achieved.

[0022] The or each insulation displacement contact has, for example, two insulation displacement legs spaced apart from one another to form an insulation displacement slot with a slot opening at the free end for contacting at least one wire section seated in the contact slot of the associated insertion pocket. The insulation displacement legs, when assembled or joined, are seated in receptacles of the vertical U-legs of the insertion pocket. The contact slot of the insertion pocket and the insulation displacement slot of the insulation displacement contact are suitably aligned with one another. The slots of the insulation displacement contact and the insertion pocket expediently run axially, meaning in the axial direction with respect to the assembled state of the stator.

[0023] The insertion pocket is designed, in particular, to accommodate at least one wire section of the winding wire. The insulation displacement contact is inserted axially into the insertion pocket, for example, whereby the wire section is permanently contacted in this area. The insulation displacement slot and / or the insulation displacement legs of the insulation displacement contact are therefore preferably designed such that the at least one wire section of the winding wire inserted into the insulation displacement slot and guided there along at least one leg-side knife edge is reliably and reliably contacted.

[0024] In an advantageous embodiment, the winding wire is routed tangentially, i.e., along the tangential direction or along the circumference of the stator, to the respective insertion pocket, with the U-shaped front leg of the insertion pocket being axially extended along the tangential direction. This allows for particularly simple routing and connection of the winding wire during the winding process.

[0025] The winding wire is guided tangentially to the extended vertical U-leg and looped around it, i.e., laid around the U-leg. The extended U-leg thus acts as a laying aid and as a deflection device during the winding process. In other words, the winding wire is guided as a wire loop or loop around the extended U-leg of the insertion pocket. The winding wire is thus guided, for example, tangentially and radially towards the inside of the extended U-leg and guided away or away from the extended U-leg tangentially and radially outside. The winding wire is then pulled downwards so that it is guided into the contact slot. This ensures that the winding wire is inserted into the contact slots under tension, i.e. under a certain (mechanical) prestress, thus creating a particularly material-saving and space-compact rotating field winding.

[0026] In one possible embodiment, the free end of the extended U-leg has a chamfer or bevel facing the contact slot to aid insertion of the winding wire. When the winding wire is routed around the longer U-leg and then lowered, the winding wire automatically slides from the chamfer into the contact slot. This allows for particularly simple and low-effort installation of the winding wire.

[0027] In a preferred embodiment, the horizontal U-shaped leg of the insertion pocket is oriented along the tangential direction. The opening direction of the contact slot is oriented along the radial direction, i.e., perpendicular to the tangential direction. This ensures particularly efficient routing of the winding wire, even under tension. In other words, the winding wire runs perpendicular to the slot plane spanned by the contact slot in the contacted area, i.e., along the radial direction.

[0028] The insertion pockets are preferably arranged between two stator teeth adjacent along the tangential direction. The respective insertion pocket is advantageously arranged axially above a circumferential stator yoke of the stator core.

[0029] In an alternative development, the horizontal U-shaped legs of the insertion pockets are rotated by 90°, for example, i.e., oriented parallel or along the radial direction. The opening directions of the contact slots are accordingly oriented along the tangential direction.

[0030] An additional or further aspect of the invention provides that the or each insertion pocket has a radially outer outer contour, i.e., facing the outer circumference of the stator or the stator laminated core, as a support contour, which protrudes radially from the insertion pocket. In a suitable development, the support contour has a curved wire guide, by means of which the winding wire is transferred from a base of the contact slot from an axial to a tangential path. The support contour thus acts as a termination for the radially outer, tangential guidance of the winding wire at the insertion pocket. This ensures a particularly effective and low-cost winding process.

[0031] In a preferred embodiment, the support contour is formed on the axially extended U-leg of the insertion pocket. In other words, the support contour is designed as a radially outer widening of the U-leg of the insertion pocket. This enables particularly effective guidance of the winding wire.

[0032] The design of the pocket with a support contour as described above is considered to be an independent invention.

[0033] In particular, a corresponding stator of an electrical machine, in particular an electric motor of a motor vehicle, is also considered an independent invention. Such a stator has a stator core having a number of stator teeth and a rotating field winding arranged on the stator teeth and comprising several phases, wherein the phases of the rotating field winding are formed from a continuously wound winding wire. Such a stator further has a connection device with a number of U-shaped plug-in pockets corresponding to the number of phases, each for receiving an insulation displacement contact as a connection point for the winding wire with phase connections on a stator end face.Each of the plug-in pockets has two vertical U-legs and a contact slot arranged between them for receiving the winding wire, wherein an outer or support contour as described above is formed onto the plug-in pocket.

[0034] An additional or further aspect of the invention provides that the interconnection device has two connecting rings which are axially mounted on the opposite end faces of the stator laminated core. The connecting rings are preferably insulating, i.e. electrically non-conductive, plastic parts. The connecting rings each have a number of radially inwardly directed half-sleeve-like coil formers corresponding to the number of stator teeth, with the coils of the rotating field winding being wound around the coil formers. In other words, the coil windings forming the coils, i.e. the winding wire, are each wound around a coil carrier of the oppositely arranged connecting rings which encompasses the respective stator tooth. The coil carrier preferably has flange collars on the end faces, i.e. directed perpendicular to the longitudinal direction of the teeth, between which the available winding space is delimited.The coil carrier thus prevents the rotating field winding from sliding off the teeth of the stator.

[0035] In a particularly advantageous embodiment, the insertion pockets are integrally formed on one of the installation rings, which is also referred to below as the interconnection ring. In particular, the insertion pockets and the installation or interconnection ring are manufactured as a single injection-molded part. This ensures particularly cost-effective and effort-reduced production of the interconnection device, which subsequently has a beneficial effect on the manufacturing costs of the stator.

[0036] In a preferred application, the stator is part of an electrical machine, in particular an electric motor of a motor vehicle. The electric motor is preferably designed as an electric motor drive for an electric oil pump, for example, for a motor vehicle transmission. The use of a stator according to the invention results in a particularly practical and cost-effective machine.

[0037] Such oil pumps, and in particular so-called auxiliary or additional pumps, are used to pump oil as a lubricant, particularly for moving parts or components, for example, of a vehicle (motor vehicle) powered by an internal combustion engine, hybrid technology, or electrically. Due to its pumping properties, such an oil pump typically creates an oil circuit, for example with an oil sump to collect excess oil and / or leakage oil. An auxiliary or additional pump, driven, for example, by an electric motor or an electric motor, is often used for at least temporary lubrication or additional lubrication of transmission components of a vehicle transmission, in particular an automatic transmission. The pumped oil is often also used to cool components or additional components of the drive train of such a vehicle.

[0038] The interconnection device according to the invention is suitable and configured for a stator of an electrical machine. The stator has a rotating field winding with a number of phases, each phase comprising at least one coil, and the phases of the rotating field winding being formed from a continuously wound winding wire. The interconnection device has a number of U-shaped insertion pockets corresponding to the number of phases, each for receiving an insulation displacement contact for contacting the winding wire with phase connections on a stator end face. The or each insertion pocket is designed with two vertical U-legs and with a contact slot arranged between them for at least partially receiving the winding wire. According to the invention, one of the two vertical U-legs of the insertion pocket is designed to be longer than the other vertical U-leg along an axial direction.

[0039] The interconnection device is particularly suitable and configured for contacting an electric motor of an electric oil pump for applications in the motor vehicle and automotive sector.

[0040] An embodiment of the invention is explained in more detail below with reference to a drawing. In the drawings: Fig. 1 shows a schematic and simplified representation of an oil circuit of a motor vehicle with an electric motor oil pump, Fig. 2 in perspective view the oil pump with an electric motor, Fig. 3 and Fig. 4 shows a perspective view of a section of a stator of the electric motor with a rotating field winding and with a connection device with an insulation displacement contact and with a plug-in pocket, with a view of a radial inside of the plug-in pocket, Fig. 5 in perspective view of a section of the stator with a view of a radial outer side of the insertion pocket, Fig. 6 in front view the pocket with a view of the radial inside during a winding process in which a winding wire is placed around a U-leg of the pocket, Fig. 7 in plan view the pocket during a wrapping process, Fig. 8 in front view the plug-in pocket with a view of the radial inside when the winding wire slides into a contact slot of the plug-in pocket, and Fig. 9 in plan view the plug-in pocket when the winding wire slides into a contact slot of the plug-in pocket.

[0041] Corresponding parts and sizes are always provided with the same reference symbols in all figures.

[0042] Fig. Figure 1 shows a schematic and simplified representation of a portion of an oil circuit 2 of a motor vehicle (not shown in detail). The oil circuit 2 comprises an electric or electromotive pump 4 as a combined main oil pump and auxiliary or supplementary pump for conveying a fluid 6, in particular a (lubricating) oil, to transmission components of a vehicle transmission.

[0043] The pump 4, also referred to below as the oil pump, has an electric motor 8 as the electrical machine. During operation of the machine 8 or the pump 4, the oil 6 is sucked from an oil sump 12 via a (pump) inlet 14 by means of a vacuum line 10 and pumped via a (pump) outlet 16 into an oil line 18, which is divided into a main oil line 20 and an auxiliary or supplementary line 22.

[0044] The main oil line 20 forms a main oil circuit of the oil circuit 2 and is provided in particular for supplying and actuating hydraulic transmission actuators 24, with which, for example, the gears of a transmission arrangement 26 of a vehicle transmission, preferably designed as an automatic transmission or dual-clutch transmission, are engaged or shifted. The auxiliary or additional line 22 is accordingly in particular part of an auxiliary or additional circuit for at least temporary lubrication or additional lubrication of transmission parts, such as the transmission arrangement 26.

[0045] The oil pump 4 is in the Fig. 2 is shown in comparative detail. The oil pump 4 comprises a pump housing 28 with a pump mechanism (not shown in detail) for pumping the oil 6. The pump mechanism is drive-coupled to the engine 8. For this purpose, the engine 8 is fastened to the pump housing 28 at a first end face. On the end face of the engine 8 opposite the pump housing 28, a functional carrier 30 is provided, which carries (motor) electronics for operating the engine 8. To dissipate heat and protect the electronics, these are covered in a fluid-tight manner by a cooling structure 32. In other words, the functional carrier 30 and the cooling structure 32 form a closed electronics housing for the oil pump 4.

[0046] In the Fig. 3 to 5 show a section of a stator 34 of the machine 8. The stator 34 has a stamped stator core 36. The stator core 36 has a number of radially inwardly directed stator teeth 38, which carry, for example, a three-phase rotating field winding 40.

[0047] The following directional information is provided, particularly regarding the assembly state of the approximately cylindrical stator 34. The axial direction A is oriented along the longitudinal direction or central axis of the stator 34. The radial direction R extends from the central axis to an outer circumference of the stator 34. The tangential or azimuthal direction T is perpendicular to the axial direction A and the radial direction R, and thus oriented along the outer circumference of the stator 34.

[0048] The phases of the rotating field winding 40 are wound from a continuous, i.e., uninterrupted, winding wire 42, which is wound as a multiple coil onto the stator teeth 38. In this exemplary embodiment, the winding wire 42 is applied to the stator core 36 or the stator teeth 38, in particular, using a single-needle winding process. In the region of the stator teeth 38, the winding wire 42 is wound around them as coils and is otherwise guided, in particular, tangentially along an outer circumference of the stator 34 or the stator core 36.

[0049] The stator 34 has a connection device 44 for guiding and connecting the winding wire 42. The connection device 44 has two laying rings 46, which are axially mounted on the stator laminated core 36 at the opposite end faces. In the cutouts of the Fig. 3 to 9 only one of the laying rings 46 is shown.

[0050] The laying rings 46 each have a number of radially inwardly directed half-sleeve-like coil bodies 48 corresponding to the number of stator teeth 38, wherein the winding wire 42 of the rotating field winding 40 is wound around the coil bodies 48.

[0051] The illustrated connecting ring 46, facing the functional carrier 30, further comprises a number of U-shaped insertion pockets 50 corresponding to the number of phases of the rotating field winding 40. The insertion pockets 50 are each designed to accommodate an insulation displacement contact (clamping connector) 52. The insertion pockets 50 are integrally formed on the connecting ring 46, i.e., integrally or monolithically.

[0052] The inserted insulation displacement contacts 52 act as the respective connection point of the winding wire 42 with phase connections on the stator end face facing the functional carrier 30. For this purpose, the insulation displacement contacts 52 have an approximately U-shaped recess 54 into which the respective phase connection engages in a contacting manner in the assembled state.

[0053] The approximately U-shaped, sleeve-like insertion pocket 50 is suitable and configured to receive and contact a respective wire section of the winding wire 42. The horizontal U-leg (horizontal leg) 50a of the insertion pocket 50 is oriented along the tangential direction T, with the two vertical U-legs (vertical legs) 50b and 50c arranged perpendicularly thereto being oriented along the axial direction A. An elongated contact slot 56, in which the winding wire 42 is seated, is provided centrally between the U-legs 50b and 50c. The contact slot 56 thus runs along the axial direction A, with the contact slot 56 being open along the radial direction R.

[0054] The vertical U-legs 50b and 50c of the insertion pocket 50 each have a groove-like receiving chamber 58, which is open towards the central contact slot 56. In the receiving chambers 58 - as in the Fig. 3 to 5 indicated - the metallic insulation displacement contact 52 plugged in or pluggable.

[0055] The insulation displacement contact 52 has an approximately U-shaped cutting edge facing the insertion pocket 50. When the insulation displacement contact 52 is inserted, the winding wire 42 of the rotating field winding 40, which is designed as an insulated wire, is pressed or squeezed into the contact slot 56 in a form-fitting and force-fitting manner, while the cutting edge cuts or at least severed the insulation of the insulated wire. As a result, an electrically conductive core of the winding wire 42 is electrically conductively contacted with the insulation displacement contact 52. The insulation displacement contact 52, in turn, is contacted via the recess 54 in the assembled state with the phase connections (not shown in detail) for energizing the rotating field winding 40.

[0056] As in the Fig. As can be clearly seen in Figures 3 to 9, the vertical U-leg 50c of the insertion pocket 50 is longer than the vertical U-leg 50b along the axial direction A. In other words, a free end 60 of the U-leg 50c projects beyond the corresponding free end of the U-leg 50b along the axial direction A.

[0057] The winding wire 42 is guided tangentially, i.e. along the tangential direction T or along the circumference of the stator 34, to the respective insertion pocket 50, wherein the front U-leg 50c of the insertion pocket 50 along the tangential direction T is axially extended.

[0058] The free end 60 of the extended U-leg 50c is - as particularly in Fig. 4 - is designed with a chamfer or bevel 62 facing the contact slot 56 as an insertion aid for the winding wire 42.

[0059] As particularly in the Fig. 5, the U-leg 50c is provided with a support contour 64 on the outer circumference, i.e., a radially outer side, facing the outer circumference of the stator 34 or the stator core 36. The support contour 64 protrudes radially from the insertion pocket 50 or the U-leg 50c. The support contour 64 is, as shown, for example, in the Fig. 3, designed as a radial thickening or shoulder of the U-leg 50c.

[0060] The support contour 64 has an approximately right-angled triangle cross-sectional shape in a plane spanned by the radial direction R and the tangential direction T. The catheti are oriented along the radial direction R on the one hand and the tangential direction R on the other hand, with the hypotenuse being inclined starting from the contact slot 56 such that the U-leg 50a is increasingly radially tapered starting from the contact slot 56 along the tangential direction T.

[0061] The support contour 64 has a curved profile 66 extending from a bottom of the contact slot 56. By means of the profile 66, also referred to below as the wire guide, the winding wire 42 is converted from an axial to a tangential profile starting from the bottom of the contact slot 56. The wire section of the winding wire 42 guided radially in the contact slot 56 is axially bent and guided along the wire guide 66, so that the winding wire 42 extends along the tangential direction T at the end of the wire guide 66. The support contour 64 thus acts as a termination for the radially outer and tangential guidance of the winding wire 42 at the insertion pocket 50.

[0062] The design of the insertion pocket 50 with a support contour 64 described above is considered to be an independent invention.

[0063] The insertion pockets 50 of the laying ring 46 have an additional termination 68, which is formed as a groove-like recess on the U-leg 50a. The termination 68 serves to circumferentially or tangentially guide the winding wire 42 behind the stator teeth 38 from stator tooth 38 to stator tooth 38, so that the corresponding wire section of the winding wire 42 does not collide with the wire section guided on the support contour 64 or wire guide 66.

[0064] The winding process for equipping the stator core 36 with the rotating field winding 40 is shown below using the Fig. 6 to 9. The arrows of the Fig. 6 to 9 indicate the course of the winding wire 42 during the winding process.

[0065] To form the phase conductors or coil wires of the rotating field winding 40, the winding wire 42 is applied fully automatically to the coil bodies 48 of the stator teeth 38 of the stator core 36 using a single-needle process. The extended U-leg 50c acts as an (axially) raised and (radially) widened shoulder during the winding process.

[0066] During winding, the winding wire 42 is wound using a winding tool of a winding machine - as shown in the Fig. 6 and Fig. 7—is guided tangentially and radially on the inside to the extended U-leg 50c by a wire section designed as a coil winding. The winding tool is wider than the contact slot 56, so that the winding wire 42 is guided collision-free above the free end of the U-leg 50b on the one hand and below the free end 60 of the U-leg 50c on the other. In other words, the winding wire 42 is applied to the U-leg 50c in the region of the bevel 62.

[0067] Then the winding wire 42 is - as shown in the Fig. 8 and Fig.9—is laid or wound in such a way that it runs along the wire guide 66 of the support contour 64. This lowers the winding wire 42, i.e., moves axially downward. The wire section at the bevel 62 slides along the axial direction A and is thus drawn into the contact slot 56. This guides the winding wire 42 in the insertion pocket 50; in particular, the winding wire 42 is placed at the bottom of the contact slot 56.

[0068] The extended U-leg 50c thus acts as a laying aid and as a deflection means during the winding process. In other words, the winding wire 42 is guided as a wire loop around the extended U-leg 50c of the insertion pocket 50.

[0069] Thus, it is possible to arrange the winding wire 42 in the contact slot 56 during a winding process without using additional holding devices or the like of the winding machine. This makes it possible to wind the stator 34 with the rotating field winding 40 in one pass, i.e., without interrupting the winding process.

[0070] The invention is not limited to the exemplary embodiments described above. Rather, other variants of the invention can also be derived therefrom by those skilled in the art without departing from the scope of the invention. In particular, all individual features described in the exemplary embodiments can also be combined with one another in other ways without departing from the scope of the invention.

[0071] In particular, it is possible for the rotating field winding 40 to have more than three phases, with a correspondingly larger number of plug-in pockets 50 and insulation displacement contacts 52 being provided for interconnection. List of reference symbols 2 Oil circuit 4 Oil pump 6 Fluid / Oil 8 Electric motor / machine 10 Vacuum line 12 Oil sump 14 Entrance 16 Outlet 18 Oil pipeline 20 Main oil pipeline 22 Auxiliary line / additional line 24 Gearbox actuator 26 Gear arrangement 28 Pump housing 30 officials 32 Cooling structure 34 Stator 36 stator lamination pack 38 stator tooth 40 rotating field winding 42 winding wire 44 Interconnection device 46 Publisher's Ring 48 coil bodies 50 slip pockets 50a, 50b, 50c U-legs 52 insulation displacement contact 54 recess 56 contact slot 58 Recording Chamber 60 freelancers 62 Chamfer / Bevel 64 Support contour 66 Course / Wire guide 68 Scheduling A axial direction R Radial direction T Tangential direction

Claims

[1] Stator (34) of an electrical machine (8), in particular an electric motor of a motor vehicle, comprising - a stator core (36) having a number of stator teeth (38) and provided with a rotating field winding (40) comprising a plurality of phases arranged on the stator teeth (38), the phases of the rotating field winding (40) being formed from a continuously wound winding wire (42), - and a connection device (44) with a number of U-shaped plug-in pockets (50) corresponding to the number of phases for receiving an insulation displacement contact (52) as a connection point of the winding wire (42) with phase connections on a stator end face, wherein each plug-in pocket (50) has two vertical U-legs (50b, 50c) and a contact slot (56) arranged between them for receiving the winding wire (42), characterized bythat one of the two vertical U-legs (50c) of the insertion pocket (50) is longer than the other vertical U-leg (50b) along an axial direction (A). [2] Stator (34) according to claim 1, characterized by that the winding wire (42) is guided tangentially to the respective insertion pocket (50), wherein the front U-leg (50c) of the insertion pocket (50) along the tangential direction (T) is axially extended. [3] Stator (34) according to claim 1 or 2, characterized by that the free end (60) of the extended U-leg (50c) has a chamfer (62) facing the contact slot (56). [4] Stator (34) according to one of claims 1 to 3, characterized by , - that the horizontal U-leg (50a) of the insertion pocket (50) is oriented along the tangential direction (T), and - that the opening direction of the contact slot (56) is oriented along the radial direction (R). [5] Stator (34) according to one of claims 1 to 4, characterized by that the insertion pocket (50) has a radially outer support contour (64) which projects radially upwards from the insertion pocket (50). [6] Stator (34) according to claim 5, characterized by that the support contour (64) has a curved wire guide (66) by means of which the winding wire (42) is transferred from an axial to a tangential course starting from a bottom of the contact slot (56). [7] Stator (34) according to claim 5 or 6, characterized by that the support contour (64) is formed on the axially extended U-leg (50c) of the insertion pocket (50). [8] Stator (34) according to one of claims 1 to 7, characterized by , - that the interconnection device (44) has two laying rings (46) which are axially mounted on the opposite end faces of the stator laminated core (36), and - that the laying rings (46) each have a number of radially inwardly directed half-sleeve-like coil bodies (48) corresponding to the number of stator teeth (38), wherein the coils of the rotating field winding (40) are wound around the coil bodies (48). [9] Stator (34) according to claim 8, characterized by that the insertion pockets (50) are formed integrally on one of the laying rings (46). [10] Electrical machine (8), in particular an electric motor of a motor vehicle, preferably for an oil pump (4) of a motor vehicle transmission, with a stator (34) according to one of claims 1 to 9. [11] Connection device (44) for a stator (34) of an electrical machine (8) with a rotating field winding (40) with a number of phases, wherein the phases of the rotating field winding (40) are formed from a continuously wound winding wire (42), having a number of U-shaped plug-in pockets (50) corresponding to the number of phases for receiving one insulation displacement contact (52) each as a connection point of the winding wire (42) with phase connections on a stator end face, - wherein each plug-in pocket (50) has two vertical U-legs (50b, 50c) and a contact slot (56) arranged between them for receiving the winding wire (42), and - wherein one of the two vertical U-legs (50c) of the insertion pocket (50) is longer than the other vertical U-leg (50b) along an axial direction (A).

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