Method for producing electric motor
By making the bottom of the inclined thickened rotor bell-shaped part with deep dip and joining the stator using stamping units, the rotor imbalance and stator engagement problems are solved, and the electric motor is compact in structure and smooth in operation.
Patent Information
- Application Number
- CN202380084119.9
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- Priority Date
- 2023-02-13
- Filing Date
- 2023-12-20
- Publication Date
- 2025-07-08
AI Technical Summary
The rotor bell parts of existing electric motors have imbalance problems during the manufacturing process, resulting in vibration and noise, and the bonding process between the stator and the electronic device housing is complicated, making it difficult to achieve a compact and reliable connection.
The rotor bell-shaped member is manufactured through a deep-drawing process, so that the bottom of its bell-shaped member is inclined and thickened relative to the surrounding wall, the tensile step portion is eliminated, and sufficient structural space and imbalance compensation is provided using the inclined bottom, while using a stamping unit to ensure reliable engagement of the stator and the electronic device housing.
The balance and mechanical stability of the rotor are improved, the imbalance is reduced, and the reliable connection between the stator and the electronic device housing is ensured, making an electric motor with compact structure and smooth operation.
Smart Images
Figure CN120283349A_ABST
Abstract
Description
Field of the Invention
[0001] The invention relates to a method for manufacturing an electric motor having a motor housing, a stator with a stator carrier and a plurality of phase connectors, and an electronic device housing with a connection side joined to the motor housing, wherein a substantially pot-shaped rotor bell is manufactured by a deep drawing process. The invention also relates to a device for performing the method, a rotor for an electric motor, and an electric motor. Background Art
[0002] Rotating or rotationally symmetric components, as rotating bodies, always have at least a certain degree of imbalance due to tolerances caused by manufacturing or structure. Herein, the imbalance can in particular be understood as an asymmetric mass distribution of the (rotationally symmetric) rotating body, whereby its axis of rotation does not coincide or align with one of its principal inertia axes. When the rotating body rotates, due to the imbalance, so-called imbalance forces occur as centrifugal forces, which increase with the increase in rotational speed and cause a non-circular, eccentric rotational movement of the rotating body. Thus, due to the imbalance of the rotating body, undesired vibrations and noise generation occur during operation.
[0003] Due to the imbalance, the service life of a product having components or a rotating body and / or the service life of a bearing rotatably supporting the rotating body may be reduced. In addition, especially at high rotational speeds, there is a risk that the components and / or the bearings may be damaged or completely destroyed.
[0004] Especially in an electric motor, such as a seat adjustment drive or a window lifter drive, arranged, for example, in the area of a passenger compartment of a motor vehicle, operation with as little noise reduction as possible is desired. In addition, such an electric motor should be as structurally space-saving as possible, i.e., have as small as possible (mounted) structural dimensions. Therefore, such an electric motor requires rotationally symmetric components, such as a rotor, which has as little imbalance as possible.
[0005] Herein, in an electric motor implemented as an outer rotor, the rotor can be implemented with a deep-drawn rotor bell as part of the motor housing. The rotor bell, for example, forms a certain covering of the inner space of the electronic device housing up to the stator in the installed state.
[0006] In the assembled state, the rotor bell here should fulfill multiple functions. On the one hand, the rotor bell should ensure a rigid connection between the rotor and the permanent magnet rotor magnets, where the rotor magnets are distributed and arranged especially on the inner periphery of the bell wall of the rotor bell. In addition, the rotor bell should enable a rigid and operationally safe connection to the motor shaft, where the rotor bell typically has a through-opening for the motor shaft and an annular flange surrounding the through-opening in the region of the bell bottom to positively and / or frictionally hold the motor shaft. Additionally, an electromagnetic return path for the magnetic circuit of the rotor magnets should be provided by the rotor bell. This is typically achieved by the surrounding bell wall that carries the rotor magnets and that acts as a yoke or return path. Another function to be fulfilled by the rotor bell is to follow a stable air gap between the stator stack and the rotor magnets. In particular, the rotor bell should ensure compliance with certain minimum requirements regarding unbalance, compensability of unbalance, and good rotation of the rotor relative to the stator.
[0007] In order to eliminate or correct unbalance, the rotor bell can be balanced. In balancing, the asymmetric mass distribution of the rotor bell is corrected or compensated. This is achieved, for example, by placing or applying additional mass, or by removing or eliminating mass from the rotor bell, e.g., by means of machining methods.
[0008] A deep-drawn rotor bell, for example, has (in addition to the through-opening) a closed bell bottom and two additional drawing steps, which should improve the robustness and mechanical stability of the rotor bell. Here, the bell bottom essentially has the same wall thickness as the bell wall. Since a greater unbalance is expected due to the inaccuracies anticipated from the deep-drawing process, this drawing step design is classified as critical for unbalance compensation.
[0009] Furthermore, for example, it is necessary to join the stator to the electronic device housing during the manufacturing process, where this can only occur after the rotor bell has been joined due to the process sequence and design. Since the accessibility to the stator carrier is not provided due to the closed bell bottom for this purpose, but the stator should be pressed into the electronic device housing on the end side using a device, the joining process without a cutout in the rotor bell becomes disadvantageously difficult. Summary of the Invention
[0010] The object of the present invention is to describe a particularly suitable method for manufacturing an electric motor. In particular, reliable and simple balancing of the rotor bell should be achievable. Additionally, reliable joining of the stator should be realized. The object of the present invention is also to describe a particularly suitable device for performing the method, a particularly suitable rotor for an electric motor, and a particularly suitable electric motor.
[0011] According to the invention, the task is solved with respect to the method by means of the features of claim 1, and with respect to the device by means of the features of claim 5, and with respect to the rotor by means of the features of claim 9, and with respect to the electric motor by means of the features of claim 10. Advantageous designs and improvements are the subject matter of the dependent claims.
[0012] If method steps are subsequently described, then for the device, advantageous designs arise in particular in such a way that the device is configured to carry out one or more of the method steps. The advantages and designs mentioned with respect to the method can also be transferred analogously to the device and / or the rotor and / or the electric motor, and vice versa. Here and subsequently, the conjunction "and / or" is to be understood as meaning that the features associated by means of this conjunction can be constituted both jointly and alternatively to one another.
[0013] The method according to the invention is set up for manufacturing an electric motor and is suitable and designed for manufacturing an electric motor. Here, for example, the electric motor is part of a standard structural component which can be used as a seat adjustment drive or as a window lifter drive for four different adjustment levels. In particular, a brushless electric motor, as an (alternating current) electric machine, has a stator provided with a field winding or a stator winding, which is arranged coaxially with a rotor having one or more permanent magnets. The stator is, for example, constructed as a stack of laminations, wherein the stator teeth carry the coils of the stator winding in the stator slots between them.
[0014] The alternating current provided for supplying the electric motor or the stator winding is generated, for example, by a converter (inverter). The converter, together with the associated control electronics, is accommodated in an electronics housing which engages with the motor housing accommodating the rotor and the stator.
[0015] The stator has a stator carrier for mounting the stack of laminations in the motor housing. In addition, the stator or the stator winding has a plurality of phase connections which are interconnected or contacted with the connection side of the electronics housing for contact with the inverter.
[0016] The electric motor is in particular embodied as an outer rotor, wherein the (outer rotor) has a rotor bell provided with rotor magnets as a pole pot (rotor pot), which in the assembled state forms part of the motor housing segmentally, in particular the housing segment surrounding the stator.
[0017] "Axial" or "axial direction" is hereby and hereinafter in particular understood as being parallel (coaxial) to the axis of rotation of the electric motor, i.e. as the direction perpendicular to the end side of the stator. Accordingly, "radial" or "radial direction" is hereby and hereinafter in particular understood as the direction oriented perpendicular (transverse) to the axis of rotation of the electric motor along the radius of the stator or the electric motor. "Tangential" or "tangential direction" is hereby and hereinafter in particular understood as the direction along the periphery of the stator or the electric motor (peripheral direction, angular direction), i.e. as the direction perpendicular to the axial direction and the radial direction.
[0018] According to the method, a substantially pot-shaped rotor bell is manufactured by a deep-drawing process such that the bottom of the bell extends inclinedly with respect to the surrounding bell wall and the bottom of the bell has a greater wall thickness than the bell wall. Here, preferably, a sheet metal having a lamination thickness substantially corresponding to the wall thickness of the subsequent bottom of the bell is used for the deep-drawing process, wherein the sheet metal is deep-drawn or thinned more in the region of the bell wall.
[0019] The inclined orientation or direction of the bottom of the bell is hereby understood as an arrangement inclined with respect to the bell wall. The inclination angle with respect to the bottom of the bell measured from the bell wall is hereby designed as an obtuse angle, i.e. greater than 90º, for example between 95º and 130º, in particular between 100º and 105º, preferably approximately 103.5º. The bottom of the bell has a central through-opening for the motor shaft. Accordingly, the bottom of the bell has a funnel-shaped or frustoconical run from the through-opening to the bell wall. The through-opening is surrounded by an annular flange which projects inwardly beyond the bottom of the bell. In the assembled state, the annular flange engages non-rotatably with the motor shaft relative to the shaft.
[0020] In order to form a rotor, the rotor bell is, for example, equipped with a plurality of permanent-magnet rotor magnets. Here, the rotor magnets are distributedly arranged on and fastened to the inner wall or the inner surface of the bell wall.
[0021] In a subsequent method step, the rotor bell and the stator are inserted into the receiving part of the motor housing. Subsequently, the rotor bell and the stator are joined by means of a stamping unit, in particular pressed into the motor housing, such that an electrical connection is established between the mating head and the connection side, thereby enabling a reliable joining process of the stator with the electronic device housing. Thereby, a particularly suitable method for manufacturing an electric motor is achieved.
[0022] Accordingly, according to the invention, when designing the rotor bell, the drawing step for the bottom of the bell is dispensed with. Thus, the bottom of the bell does not have an additional drawing step. According to the invention, the drawing step is replaced by an inclined rear wall. In the joined state, the inclined run of the bottom of the bell provides sufficient structural space for the winding head of the stator or the stator winding, such that an electric motor with a particularly compact structural space can be manufactured.
[0023] The thickening at the bottom of the bell-shaped part ensures the necessary robustness and mechanical stability of the rotor bell-shaped part. In addition, the thickening at the bottom of the bell-shaped part simultaneously realizes a defined "balance plane" for imbalance compensation, which enables a wider and deeper milling of the material for the balancing process compared to a rotor bell-shaped part with a tensile step, thereby achieving a larger imbalance margin for, in particular, negative imbalance compensation.
[0024] In an advantageous refinement, during manufacturing, negative imbalance compensation is performed on the bottom of the bell-shaped part. For example, the imbalance of the rotor bell-shaped part can be reduced by a cutting method, in which material is removed or taken away from the bottom of the bell-shaped part. Alternatively, for example, laser ablation or laser ablation can also be considered for imbalance compensation. Preferably, the imbalance compensation is performed after fastening the rotor magnet and before the joining process.
[0025] In a suitable design, a deep drawing process is performed such that the bottom of the bell-shaped part has a wall thickness between 40% and 60%, in particular between 40% and 50%, greater than the wall of the bell-shaped part. For example, the bottom of the bell-shaped part has a wall thickness of approximately 2 mm (millimeters), and the wall of the bell-shaped part has a wall thickness of approximately 1.2 mm (millimeters). During negative balance compensation, the wall thickness of the bottom of the bell-shaped part is locally reduced to, for example, approximately 0.5 mm.
[0026] In an additional or alternative aspect of the present invention, at least one perforated void is introduced into the bottom of the bell-shaped part. Preferably, a plurality of voids, i.e., at least two voids, preferably three voids, are introduced into the bottom of the bell-shaped part. For example, here, these voids are arranged tangentially distributed radially outside the central through-opening. The voids are introduced into the bottom of the bell-shaped part, for example, by punching. Preferably, the voids are introduced after the deep drawing process, thereby ensuring positioning without the risk of deformation.
[0027] The stamping unit suitably has at least one punch projection. Suitably, the stamping unit has a number of punch projections corresponding to the number of voids. Thus, the number of voids and the number of punch projections are complementary. During the joining process, at least one void is penetrated by at least one punch projection such that the punch projection directly abuts against the end side of the stator carrier. Thus, through the voids, the stamping unit directly, i.e., non-indirectly, abuts against the stator carrier, thereby ensuring a particularly reliable and process-safe joining process of the stator to the electronic device housing.
[0028] For example, three holes having, for example, a bean-shaped cross-sectional shape are introduced into the bottom of the bell-shaped part, and the punch projections for joining the stator during the process can pass through these holes in order to be able to be pressed onto the stator or the stator carrier, and thus the stator is pressed into the electronic device housing in a process-safe manner, so that the phase connection head reliably contacts the connection side.
[0029] The device according to the invention is configured to carry out the method described above and is suitable and designed to carry out the method described above. The device here has a deep-drawing device for manufacturing the rotor bell and a stamping unit for joining the rotor bell and the stator in the motor housing. Thereby, a favorable device for manufacturing an electric motor is achieved.
[0030] In an advantageous embodiment, the stamping unit has a abutment surface for the end side of the bell bottom and at least one punch projection protruding axially from the abutment surface for passing through the clearance in the rotor bell and for directly abutting on the end side of the stator carrier of the stator. Thereby, a particularly favorable stamping unit for joining the rotor, stator, and motor housing is achieved.
[0031] In a suitable refinement, the stamping unit has a cylindrical joining punch for joining. Here, preferably, the abutment surface and at least one punch projection are arranged on the end side of the joining punch. Here, the joining punch has a column-sector-shaped receiving portion for the motor shaft of the electric motor extending in the axial direction (longitudinal direction of the joining punch). A motor shaft equipped, for example, with additional components (such as the worm shaft of a worm drive) can be radially inserted into the joining punch through the receiving portion, such that the components of the motor shaft and the rotor bell are arranged on opposite sides of the abutment surface. Through the receiving portion, it is ensured during the joining process (pressing-in process) that no undesired forces act on the motor shaft or the components fastened to the motor shaft.
[0032] In a preferred design, the stamping unit has a stamping flange surrounding the joining punch, which at least sectionally surrounds the motor housing during the joining process. Thus, the motor housing is preferably held in the stamping flange in a form-locking manner in the radial direction. Thus, during the stamping movement for joining the rotor and the stator in the motor housing, a particularly high joining accuracy or pressing-in accuracy is ensured.
[0033] The rotor according to the invention is configured to and is suitable and designed for an electric motor, such as a seat adjustment drive or a window lifter drive. The rotor is preferably manufactured within the scope of the method described above and has a substantially pot-shaped rotor bell, which has a bell bottom and a surrounding bell wall, wherein the bell bottom extends inclined relative to the bell wall, and wherein the bell bottom has a greater wall thickness than the bell wall. Thereby, a particularly suitable rotor for an electric motor is achieved. The bell bottom does not have an additional drawing step, and a particularly high imbalance margin for negative imbalance compensation can be achieved through the increased wall thickness or wall thickness, such that particularly smooth operation of the electric motor can be achieved with the rotor.
[0034] The electric motor according to the invention is provided for, suitable for and designed for a motor vehicle, in particular for a seat adjustment drive or a window lifter drive. The electric motor is preferably manufactured according to the method described above.
[0035] The electric motor has a stator and a rotor, which are accommodated in a motor housing. An electronic device housing for accommodating the electronics of the electric motor is joined to the motor housing. The electronic device housing has a connection side for contacting and interconnecting a plurality of phase connectors. The stator has a stator winding, which terminates in phase connectors. For example, the stator winding is applied to a stator lamination stack, wherein the lamination stack is held by a stator carrier. The rotor has a rotor bell as a pole pot, which is equipped with permanent magnet rotor magnets on the inside.
[0036] The rotor or the rotor bell and the stator are inserted into a receiving part of the motor housing and joined to the motor housing, thereby establishing an electrical connection between the phase connectors of the stator and the connection side of the electronic device housing. Thus, a particularly suitable electric motor is achieved. BRIEF DESCRIPTION OF THE DRAWINGS
[0037] Subsequently, embodiments of the invention are explained in detail with the aid of the drawings. In which:
[0038] Figure 1 The electric motor is shown in a perspective sectional view, which has a motor housing, an electronic device housing, a stator and a rotor,
[0039] Figure 2 The rotor bell of the rotor is shown in a perspective view,
[0040] Figure 3 The rotor bell is shown in a sectional view,
[0041] Figure 4 The stamping unit for joining the rotor and the stator to the motor housing is shown in a perspective view,
[0042] Figure 5 The joining process is shown in a perspective view, and
[0043] Figure 6 The stamping unit and the electric motor during the joining process are shown in a sectional view.
[0044] Corresponding parts and dimensions are always provided with the same reference numerals in all the figures. DETAILED DESCRIPTION
[0045] Figure 1 The electric motor 2 is shown as an adjustment or drive motor, which is used, for example, for longitudinal adjustment of the seat of a motor vehicle seat.
[0046] The electric motor 2 is embodied as a brushless outer rotor, which has a wound stator 4 and a rotor 8 with rotor magnets 6 provided with permanent magnets. The rotor 8 is fixedly joined to the rotatably supported motor shaft 10 relative to the shaft. A screw-shaped worm shaft 12 is arranged on the motor shaft 10 for driving a transmission gear (not shown in detail).
[0047] The electric motor 2 is connected to an (motor) electronic device 14, which is arranged in an electronic device housing 16. The electronic device housing 16 has an electronic device carrier 18 and an electronic device cover 20. The electronic device housing 16 is arranged on the end side of the electric motor 2 opposite to the worm shaft 12.
[0048] The stator 4 has a (stator) lamination stack 22, which has a central through-opening, into which a sleeve-shaped or tubular stator carrier 24 is inserted. For example, two mutually linked rings (contact units) 25 are placed on the opposite end sides of the lamination stack 22 for guiding and interconnecting the coil wires of the stator winding 26. However, the mutually linked rings 25 and the stator carrier 24 can also be designed as a common component here, for example, designed as an injection-molded encapsulation part of the lamination stack 22. Here, Figure 6 a separate embodiment of the mutually linked rings 25 and the stator carrier 24 is shown, wherein, Figure 1 in particular, a one-piece embodiment as an injection-molded encapsulation part is shown. The stator carrier 24 is made of a non-conductive, mechanically stable plastic material.
[0049] A polyphase rotating field winding is applied as the stator winding 26 to the lamination stack 22 or the stator carrier 24. The winding ends or coil ends are guided in the direction of the connection side 30 of the electronic device housing 16 as phase connectors 28.
[0050] The stator 4 and the rotor 8 are located in a motor housing 32 connected or joined to the electronic device housing 16, which surrounds the rotor 8 on the outer peripheral side. The stator 4 and the rotor 8 are inserted into a receiving part 34 here. In the inserted state, the stator carrier 24 holds the stator 4 relative to the housing fixedly with respect to the motor housing 32, wherein the phase connectors 38 are interconnected with the connection side 30, for example, interconnected with the electronic device 14 through a (piercing) clip contact part.
[0051] Subsequently, with the aid of Figure 2 and Figure 3 the structure of the (outer rotor) rotor 8 is elaborated in detail.
[0052] The rotor 8 has a rotor bell (rotor can, pole can) 36. The rotor bell 36 mainly has a bell bottom 38 and a surrounding bell wall 40.
[0053] The bell-shaped part wall 40 is a hollow cylindrical or tubular annular wall that surrounds the outer periphery of the stator 4 in the assembled state, and rotor magnets 6 are arranged on its inner side or inner surface.
[0054] The bell-shaped part bottom 38 has a central through-opening 42 for receiving the motor shaft 10. The through-opening 42 is surrounded by an inwardly protruding annular flange 44 that forms a mechanical interface for fastening the motor shaft 10.
[0055] The bell-shaped part bottom 38 has a substantially circular-ring-shaped rotor hub 46 with a through-opening 42 and an annular flange 44, which is arranged substantially perpendicular to the bell-shaped part wall 40. The bell-shaped part bottom 38 also has a bottom section 48 that connects the rotor hub 46 to the bell-shaped part wall 40, and this bottom section is oriented obliquely with respect to the rotor hub 46 and the bell-shaped part wall 40. The substantially funnel-shaped or frustum-shaped bottom section 48 does not have additional stretching steps. The inclination angle 50 between the bottom section 48 and the bell-shaped part wall 40 is implemented as an obtuse angle greater than 90°. For example, the inclination angle is designed to be between 100° and 110°, for example, designed to be approximately 105°, preferably 103.5°.
[0056] The rotor bell 36 is manufactured as a deep-drawn part and is deep-drawn during manufacturing such that the bell-shaped part bottom 38 is inclined and the bell-shaped part bottom 38 has a wall thickness or wall thickness that is greater than that of the bell-shaped part wall 40. In a suitable design, the deep-drawing process is carried out such that the bell-shaped part bottom 38 has a wall thickness that is 40% to 60% greater than that of the bell-shaped part wall 40. In the shown embodiment, the bell-shaped part bottom 38 has a wall thickness that is approximately 50% greater than that of the bell-shaped part wall 40. Preferably, during the manufacture or assembly of the electric motor 2, negative imbalance compensation is performed on the bell-shaped part bottom 38 of the rotor 8.
[0057] In the region of the rotor hub 46, three elliptical or bean-shaped cutouts 52 are arranged tangentially around the through-opening 42. The hole-shaped cutouts 52 are introduced, for example, by punching before or after the deep-drawing process.
[0058] To manufacture the electric motor 2, the rotor bell 36 is manufactured by a deep-drawing process using a deep-drawing device not shown in detail as described above. The rotor bell 36 or the rotor 8 and the stator 4 are together inserted into the receiving part 34 of the motor housing 32, and then joined to, in particular, pressed into the motor housing using a stamping unit 54. Here, an electrical connection is achieved between the phase connection head 28 and the connection side 30 of the electronic device housing 16.
[0059] Subsequently, with the help of Figures 4 to 6 The joining process is elaborated in detail.
[0060] Figure 4Shown is a movable punch head 56 of a punching unit 54 for joining or pressing the rotor 8 and the stator 4 into the motor housing 32. The punch head 56 can be moved, for example, electrically, hydraulically or pneumatically in order to carry out the joining process or the pressing process.
[0061] The punch head 56 has a punching plate 58, on which a vertically protruding joining punch 60 is formed. The joining punch 60 is surrounded by an annular punching flange 62. The joining punch 60 is substantially columnar, and the coaxially arranged punching flange 62 is substantially hollow columnar.
[0062] The joining punch 60 and the punching flange 62 are open on one side. Here, the joining punch 60 has a column-sector-shaped cutout as a receiving portion 64, which is arranged radially aligned with a corresponding cutout 66 of the punching flange 62. Here, the receiving portion 64 and the cutout 66 extend over the entire (axial) length or height of the joining punch 60 or the punching flange 62, respectively.
[0063] The joining punch 60 has a contact surface 68 for the bottom 38 of the bell-shaped part, in particular for the end face of the rotor hub 46. Three axially protruding punch projections 70 are formed on the contact surface 68. The punch projections 70 have a cross-sectional shape that is complementary to the cross-sectional shape of the cutout 52. Here, the punch projections 70 have an axial height greater than the wall thickness of the bottom 38 of the bell-shaped part. The punch projections 70 are provided and designed to pass through the cutout 52 during the joining process or the pressing process and to directly abut against the end face of the stator carrier 24 ( Figure 6 )
[0064] To manufacture the electric motor 2, the stator 4, the rotor 8 and the motor shaft 10 are inserted into the motor housing 32. Subsequently, the pre-assembled electric motor 2 is inserted into the receiving portion 64 in the radial direction through the cutout 66, such that the motor housing 32 is segmentally surrounded in a form-fitting manner in the radial direction by the punching flange 62, and the cutout 52 is arranged opposite the assigned punch projection 70. As can be seen, for example, in Figure 5 the motor shaft 10 is located in the receiving portion 64 together with the worm shaft 12.
[0065] Subsequently, the punching unit 54 is actuated, and the punch head 56 moves linearly in the axial direction onto the motor housing 32. Thereby, the contact surface 68 first contacts the rotor hub 46 and presses the rotor 8 in the direction of the receiving portion 34. Here, the punch projections 70 contact the stator carrier 24, whereby the stator 4 is reliably pressed into the motor housing 32 or the receiving portion 34. Thus, the punch head 56 abuts directly or indirectly against the rotor 8 and the stator 4 during the joining process, thereby enabling a reliable and safe pressing into the motor housing 32. Here, the phase connection head 28 is interconnected or contacted with the connection side 30.
[0066] The claimed invention is not limited to the above embodiments. On the contrary, other variants of the invention can also be derived by those skilled in the art within the scope of the disclosed claims without departing from the subject matter of the claimed invention. In particular, all the individual features described in connection with different embodiments can also be combined in other ways within the scope of the disclosed claims without departing from the subject matter of the claimed invention.
[0067] List of reference numerals
[0068] 2 Electric motor
[0069] 4 Stator
[0070] 6 Rotor magnets
[0071] 8 Rotor
[0072] 10 Motor shaft
[0073] 12 Worm shaft
[0074] 14 Electronic device
[0075] 16 Electronic device housing
[0076] 18 Electronic device carrier
[0077] 20 Electronic device cover
[0078] 22 Laminated core
[0079] 24 Stator carrier
[0080] 25 Interlinking ring
[0081] 26 Stator winding
[0082] 28 Phase connector
[0083] 30 Connecting side
[0084] 32 Motor housing
[0085] 34 Receiving part
[0086] 36 Rotor bell
[0087] 38 Bell bottom
[0088] 40 Bell wall
[0089] 42 Through-opening
[0090] 44 Annular flange
[0091] 46 Rotor hub
[0092] 48 Bottom section
[0093] 50 Inclination Angle
[0094] 52 Empty Portion
[0095] 54 Stamping Unit
[0096] 56 Stamping Head
[0097] 58 Stamping Plate
[0098] 60 Joining Punch
[0099] 62 Stamping Flange
[0100] 64 Accommodating Portion
[0101] 66 Empty Portion
[0102] 68 Contact Surface
[0103] 70 Punch Protrusion
Claims
1. A method for manufacturing an electric motor (2), the electric motor having a motor housing (32) and a stator (4) with a stator carrier (24) and a plurality of phase connectors (28), and an electronic device housing (16) with a connection side (30) joined to the motor housing (32), - Among them, A substantially pot-shaped rotor bell (36) is manufactured by a deep drawing process such that the bell bottom (38) extends inclinedly with respect to the surrounding bell wall (40), and the bell bottom (38) has a wall thickness greater than that of the bell wall (40), - wherein the rotor bell (36) and the stator (4) are inserted into a receiving portion (34) of the motor housing (32), - wherein the rotor bell (36) and the stator (4) are joined to the motor housing (32) by means of a stamping unit (54), thereby establishing an electrical connection between the phase connectors (28) and the connection side (30).
2. The method according to claim 1, wherein Negative unbalance compensation is performed on the bell bottom (38).
3. The method according to claim 1 or 2, characterized in that, The deep drawing process is performed such that the bell bottom (38) has a wall thickness between 40% and 60% greater than that of the bell wall (40).
4. The method according to any one of claims 1 to 3, characterized in that At least one void (52) is introduced into the bell bottom (38), wherein the stamping unit (54) has at least one punch projection (70) which, during joining, passes through the void (52) and bears directly against the end side of the stator carrier (24).
5. An apparatus for manufacturing an electric motor (2) according to any one of claims 1 to 4, the apparatus having a deep drawing device for manufacturing a rotor bell (36) and a stamping unit (54) for joining the rotor bell (36) and the stator (4) to a motor housing (32).
6. The device according to claim 5, characterized in that, The stamping unit (54) has a bearing surface (68) for the end side of the bell bottom (38) and at least one punch projection (70) axially protruding from the bearing surface (68), the punch projection being for passing through the void (52) of the rotor bell (36) and for bearing directly against the end side of the stator carrier (24).
7. The device according to claim 5 or 6, characterized in that, The stamping unit (54) has a cylindrical joining punch (60) for joining, wherein the joining punch (60) has an axially extending column-sector-shaped receiving portion (64) for the motor shaft (10).
8. The device according to claim 7, characterized in that, The stamping unit (54) has a stamping flange (62) surrounding the joining punch (60), the stamping flange at least sectionally surrounding the motor housing (32) during the joining process.
9. Rotor (8) for an electric motor (2), the rotor having a substantially pot-shaped rotor bell (36), the rotor bell having a bell bottom (38) and a surrounding bell wall (40), wherein, The bell bottom (38) extends inclinedly with respect to the bell wall (40), and wherein the bell bottom (38) has a wall thickness greater than that of the bell wall (40).
10. An electric motor (2) for a motor vehicle, the electric motor having: - a motor housing (32), - a stator (4), the stator having a stator carrier (24) and a plurality of phase connectors (28), - An electronic device housing (16) with a connection side (30) joined to a motor housing (32), and - A rotor bell (36), - Among them, wherein the rotor bell (36) and the stator (4) are inserted into a receiving portion (34) of the motor housing (32), and - wherein the rotor bell (36) and the stator (4) are joined into the motor housing (32) such that an electrical connection is established between the phase connection head (28) and the connection side (30).