Drive unit

Abstract

The present invention relates to a drive unit (1), having at least one motor (2), at least one transmission (3) and at least one housing (4), wherein the motor (2) has at least one stator (7) and at least one rotor (8), and wherein the transmission (3) is arranged at least partially in an internal volume (9) of the rotor (8). A drive system that is energy-efficient, compact and easy to install is implemented in that the transmission (3) is in the form of a transmission unit arranged in a transmission housing (10).

Description

[0001] P45614PC00 / V / V ​​07.08.2025

[0002] 1

[0003] Dr. Fritz Faulhaber GmbH & Co. KG, Faulhaberstraße 1, 71101 Schönaich

[0004] "Drive unit"

[0005] The invention relates to a drive unit comprising at least one motor, at least one gearbox, and at least one housing, wherein the motor has at least one stator and at least one rotor. The gearbox is arranged at least partially within an internal volume of the rotor.

[0006] Drive units with an internal rotor electric motor and a gearbox integrated within the rotor's internal volume combine the advantages of compact design with high power density and precise power transmission. Such designs are particularly in demand for applications requiring both efficient electrical drive power and mechanical transmission.

[0007] The gearbox is, for example, a planetary gearbox, spur gearbox, tension shaft gearbox, worm gearbox, or another compact gearbox design capable of changing the rotor's speed and torque before transmitting them to an output element. Integrating a gearbox within the rotor allows for a compact design, as no additional space is required for an external gearbox.

[0008] However, the solutions known from the state of the art for energy-efficient and compact drive systems have the disadvantage that assembly is usually very complex.

[0009] The present invention therefore aims to provide a drive system that is energy-efficient, compact, and easy to install. P45614PC00 / V / V ​​07.08.2025

[0010] 2

[0011] The aforementioned problem is solved in a drive unit of the generic type with the features of the characterizing part of claim 1, namely by the fact that the transmission is designed as a transmission unit arranged in a transmission housing.

[0012] The drive unit according to the invention comprises at least one motor and at least one gearbox. The motor has at least one rotor and at least one stator. The motor is preferably designed as an internal rotor, so that the rotor is arranged inside the stator. The internal rotor design has the particular advantage of improving the temperature distribution during operation. Furthermore, in the present drive unit, the gearbox is arranged at least partially, and in particular completely, within an internal volume of the rotor.

[0013] According to the invention, the gearbox is arranged entirely within a gearbox housing. The gearbox housing preferably completely surrounds the gearbox. The gearbox housing is, for example, designed as a sleeve surrounding the gearbox. The sleeve preferably completely encloses the gearbox in a direction parallel to the gearbox's axis of rotation. In particular, the gearbox housing is designed such that the gearbox components are essentially flush with the gearbox housing in the axial direction along an axis of rotation. The gearbox housing is, in particular, essentially circular. The gearbox forms a gearbox unit within the housing and can be inserted into and removed from the motor, especially into an internal volume of the rotor, as a module.

[0014] Preferably, the gearbox is arranged within an axial extent of the active motor part. For example, the gearbox is surrounded radially by the stator windings. In particular, the gearbox extends in P45614PC00 / V / V ​​07.08.2025

[0015] 3. axial direction completely along the axial extent of the stator windings.

[0016] The gearbox has at least one output element through which the gearbox torque is transmitted. The output element is preferably mounted on an inner circumference of the gearbox housing, for example by a bearing such as a ball bearing. Preferably, the output element is essentially disc-shaped. With respect to a back plate of the rotor, the gearbox is preferably arranged opposite the electronic unit of the drive unit.

[0017] Preferably, all components of the gearbox are arranged within the gearbox housing. During assembly, the rotor, in particular a rotor shaft or a pinion shaft, is inserted into the gearbox unit.

[0018] Alternatively, during assembly, the gearbox unit is slid onto a rotor shaft or a pinion shaft. In the assembled state, the gearbox housing is positioned between the rotor and the gearbox. The gearbox housing is preferably mounted in a fixed position within the motor. For example, the gearbox housing is positively, mechanically, and / or materially fitted into a front flange of the motor housing. In particular, the front flange is pressed and / or welded or bonded into the housing. The gearbox housing is made, for example, of a metal such as aluminum or hardened steel.

[0019] Furthermore, the drive unit housing has a front flange and at least one back plate. The front flange and / or the housing are preferably made of a metal, e.g., aluminum or hardened steel. The output element of the drive unit passes through the front flange. The back plate preferably has a recess for the motor's connecting cables. The front flange of the motor housing has, for example, at least one cable guide. The front flange of the motor is, for example, connected to the housing P45614PC00 / V / V ​​07.08.2025

[0020] 4 of the drive unit is welded. The housing of the drive unit preferably completely surrounds the drive unit.

[0021] All gearbox components are pre-assembled within the gearbox housing, allowing the motor and rotor shaft to be inserted for installation. Alternatively, the gearbox can be connected to the motor by sliding it onto the rotor shaft and then mounted inside the motor. The gearbox housing serves as a bearing for the gearbox components within the motor.

[0022] It is particularly preferred that the motor rotor is fully supported within the gearbox. In particular, it is preferred that the rotor is supported within the gearbox along its axial extent. For example, the rotor is supported via the rotor shaft by means of ball bearings in planetary carriers of the gearbox.

[0023] The drive unit according to the present invention is designed to be particularly compact. For example, the ratio of diameter to length is in the range between 2 and 4, preferably it is about 3.

[0024] The invention offers an advantage over the prior art in that the modular design of the drive unit, consisting of a motor and gearbox, simplifies assembly. Furthermore, particularly in connection with the features of the dependent claims, a drive unit is specified which exhibits low reverse torque with low friction and detent torque.

[0025] By using a different gearbox unit, different gear ratios can be advantageously achieved without having to change the interfaces to the motor.

[0026] The invention is particularly suitable for use in robotics, exoskeletons, and prostheses. The invention therefore relates in particular to a robot with at least one drive unit according to an embodiment of P45614PC00 / V / V ​​07.08.2025.

[0027] 5 of the present invention, or an exoskeleton with at least one drive unit according to an embodiment of the present invention, or a prosthesis with at least one drive unit according to an embodiment of the present invention. Preferably, the robot, the exoskeleton, or the prosthesis has a plurality of drive units according to an embodiment of the present invention.

[0028] Depending on its design, the drive unit according to the present invention could also be referred to as a flat BLDC drive unit with integrated gearbox and control, or as a flat BLDC geared motor with integrated control, or as a flat BLDC servo drive with integrated gearbox.

[0029] One embodiment of the drive unit provides that the transmission is designed as a planetary gear unit, preferably a single-stage unit. The ring gear and the planet gears are arranged within the transmission housing. The ring gear of the planetary gear unit is supported, for example, by an inner circumference of the transmission housing. Alternatively, the ring gear is formed integrally with the transmission housing, for example, from steel, particularly hardened steel. The sun gear is, for example, designed as a pinion and arranged on the rotor shaft or pinion shaft. Preferably, the pinion is welded to the rotor shaft. The rotor shaft is preferably pressed into a receptacle in a projection of a pole wheel. The rotor shaft is supported, for example, in the receptacle of the pole wheel and, opposite it, preferably by a bearing, e.g., a ball bearing, in a first planet carrier of the planetary gear unit.

[0030] The gearbox housing is, for example, formed in one piece, in particular also in one piece with the ring gear. Alternatively, the gearbox housing is designed to be formed in two pieces. In particular, a first housing part is pushed or screwed onto a second housing part. For example, the ring gear is formed in one piece with the first housing part or the second housing part. P45614PC00 / V / V ​​07.08.2025

[0031] 6

[0032] The first planet carrier, for example, has an outwardly open bearing shoulder. The first planet carrier can also be the output element of the gearbox. Preferably, at least one disc-shaped cable guide is attached to the output element or to the planet carrier. The first planet carrier is supported, for example, by a bearing element, such as a ball bearing, on an inner circumference of the gearbox housing. The gearbox housing and the planet carrier have corresponding bearing shoulders for this purpose.

[0033] Preferably, the gearbox has at least one second planet carrier. The second planet carrier is preferably arranged opposite the first planet carrier in the gearbox housing. The first and second planet carriers are preferably essentially circular disk-shaped. The first and second planet carriers preferably have substantially the same diameter. The first and second planet carriers are preferably made of a metal, for example, steel or aluminum. The second planet carrier is, for example, mounted on a projection of a rotor's pole wheel. Furthermore, the second planet carrier is mounted, preferably by means of a bearing, on an inner circumference of the gearbox housing.

[0034] The use of two planetary carriers makes it possible to assemble and test the gearbox as a self-contained pre-assembly unit. Furthermore, the rotor can be mounted and installed independently of the housing. This results in an advantageous modular design for the drive unit.

[0035] Preferably, the three planet gears of the planetary gear set are designed as stepped planet gears. The stepped planet gears allow the reduction ratio to be increased without requiring a two-stage planetary gear set. This minimizes the load on the rotor and simultaneously increases efficiency. It is also specifically intended that the P45614PC00 / V / V ​​07.08.2025

[0036] 7

[0037] The planet gears are designed as simple planet gears. The transmission is preferably designed for a maximum torque between 12 Nm and 20 Nm, in particular 16 Nm, and / or a continuous torque between 5.5 Nm and 9.5 Nm, in particular 7.5 Nm.

[0038] Preferably, the planetary gears and / or the ring gear of the planetary gearbox are made of a sintered material, in particular a sintered metal. The pinion on the rotor shaft is preferably milled to advantageously ensure sufficient stability.

[0039] Another embodiment of the drive unit provides that the transmission has at least one ring gear. The ring gear interacts with the transmission housing in a positive-locking manner. Preferably, the ring gear interacts with the transmission housing in such a way that it cannot rotate within the transmission housing. For example, the ring gear has at least one projection that interacts with a recess on the transmission housing, or vice versa. Preferably, at least one positive-locking element, e.g., a pin, a key, or a keyway, is provided, and this positive-locking element engages in a first groove on the transmission housing and a second groove on the ring gear. The positive-locking element prevents rotation of the ring gear relative to the transmission housing. Alternatively, the ring gear and the transmission housing interact by means of an interference fit to prevent relative movement.Preferably, the ring gear and / or at least one or all planet gears are made of a sintered material. Alternatively, the ring gear is formed integrally with at least part of the gearbox housing.

[0040] To preferably reduce wear and increase the service life of the gearbox, a further embodiment provides that at least the planetary gears of the planetary gearbox are supported by needle bearings. The needle bearings are located, in particular, between the planetary gear and the respective P45614PC00 / V / V ​​07.08.2025

[0041] 8

[0042] The bearing pin is arranged. Preferably, the needle bearing has only an outer sleeve and a needle race to achieve a low radial height. An inner sleeve is specifically omitted.

[0043] In particular, it is provided that the bearing pins or pins are at least partially inserted into the first planet carrier and / or the second planet carrier, in particular pressed in. For example, the bearing pins are welded to the planet carrier(s). Alternatively, the first planet carrier and the second planet carrier are joined together by means of a plurality of screws, in particular clamped against each other. For example, a length of spacers arranged around the screws determines a preload between the planet carriers or on the ball bearings. The bearing pins are, for example, designed as standard cylindrical pins.

[0044] Preferably, the needle bearings are arranged within the axial extent of the planet gears along the axis of rotation.

[0045] Depending on the application, it is advantageous to reduce the rotor's moment of inertia, particularly in applications with frequent changes in direction and load. In this context, a further embodiment has shown it to be advantageous for the rotor to have at least one pole wheel. The pole wheel has at least one back section, and this back section has at least one recess for weight reduction. By recessing the back section of the pole wheel, at least partially, for example by means of polygonal or circular recesses, the overall weight of the drive unit and, in particular, the rotor's moment of inertia can be further reduced. The back section of the rotor or pole wheel is, in particular, the section that extends substantially perpendicular to the axis of rotation. P45614PC00 / V / V ​​07.08.2025

[0046] 9

[0047] This embodiment has the advantage that less torque is required to accelerate / brake the motor, resulting in increased efficiency and therefore lower energy consumption.

[0048] According to a further embodiment of the drive unit, it has proven advantageous for mounting the rotor magnets if the rotor has a plurality of magnets, and if the magnets are arranged in a bearing cage. The bearing cage is made, for example, of plastic. Preferably, the bearing cage is arranged on the outer circumference of the pole wheel. The magnets are arranged in individual recesses in the bearing cage and connected to the bearing cage and / or to the pole wheel. In particular, exactly one magnet is arranged in each recess. Preferably, the bearing cage completely surrounds the pole wheel. The bearing cage preferably has a plurality of recesses that essentially correspond to the outer contour of a magnet. Preferably, the magnets in the recesses are bonded to the bearing cage and / or to the pole wheel. It is particularly recommended that the bearing cage be formed integrally with the pole wheel.The flywheel and the bearing cage are preferably made of the same material. For example, the flywheel and bearing cage are manufactured using sintering or an additive manufacturing process, e.g., 3D printing.

[0049] An alternative embodiment provides that the pole wheel has a plurality of flat surfaces on its outer circumference, and that at least one magnet is attached to each surface. Preferably, the number of flat surfaces corresponds to the number of magnets. In particular, the flat surfaces border each other over the entire circumference. For example, the magnets are either glued or potted onto the surface. The potting is preferably carried out on one or both sides. Preferably, a chamfer is provided for the potting compound on at least one edge, and preferably on both edges of the pole wheel.

[0050] To reduce the size of the drive unit, a further embodiment has proven advantageous in which the motor's electronics unit is mounted on the stator. The electronics unit P45614PC00 / V / V ​​07.08.2025

[0051] The device 10 preferably comprises at least one encoder and / or one motor controller and / or one temperature sensor. Preferably, the encoder and / or one motor controller and / or one temperature sensor are arranged on a printed circuit board. The encoder is, for example, configured as an optical encoder, e.g., with a clock disk and an optical encoder chip, or as a magnetic encoder. The encoder is preferably configured as an absolute encoder, for example, as a 14-bit magnetic absolute encoder. Such an encoder has the advantage that its high resolution allows simultaneous electrical commutation as well as position and speed control. Optionally, additional Hall sensors are provided, which are used solely for commutation.

[0052] It is particularly preferred that the electronic unit comprises at least or exactly two printed circuit boards, preferably a first printed circuit board for the encoder and / or motor controller and / or temperature sensor, and a second printed circuit board for contacting the stator coils. Preferably, the two printed circuit boards are stacked and connected, for example, by soldering, particularly electrically. Preferably, at least one Hall sensor of an encoder is arranged on at least one printed circuit board to interact with a magnet located on the rotor. Preferably, at least one magnetic angle encoder is arranged on at least one printed circuit board, preferably the first printed circuit board. The angle encoder comprises, for example, at least one encoder chip with integrated Hall sensor elements.

[0053] Preferably, the circuit boards of the electronic unit are contacted together by means of a plurality of rigid contact pins. Preferably, the contact pins are oriented substantially orthogonally to a top surface of the circuit boards. Preferably, the contact pins are attached to one of the circuit boards, e.g., soldered, and are passed through contact openings in the second circuit board, thereby making contact or optionally being soldered.

[0054] Preferably, at least one printed circuit board, in particular the printed circuit board for contacting the coils of the stator, is mounted radially on a P45614PC00 / V / V ​​07.08.2025

[0055] The outer end face of the circuit board has a plurality of recesses, particularly U-shaped grooves, for the coil conductors or the winding wire. The winding wire is inserted into a groove or recess and then laid flat on the top side of the circuit board. Each conductor is preferably soldered to a solder pad on the top side of the circuit board. The recesses guide the conductors advantageously and protect them from mechanical stresses during subsequent processes. This offers the advantage of simple and reliable wire routing, even for high-pole internal rotors.

[0056] For example, it is provided that at least one printed circuit board has at least one or exactly two connectors, in particular circular connectors, to connect the motor phases and / or the sensors, e.g., a rotary encoder. The connectors are preferably connected by means of contact pins and corresponding sockets or solder contacts arranged on the printed circuit board.

[0057] The housing of the drive unit is preferably circular. In particular, the electronic unit is completely enclosed within the housing of the drive unit. For example, at least one coding means is provided on the stator to define the orientation of the circuit board in conjunction with corresponding recesses on at least one circuit board. Preferably, both circuit boards interact with the coding means. On the side of the electronic unit facing away from the motor, a feedthrough for the connecting cables of the electronic unit is preferably provided.

[0058] The coding elements are arranged asymmetrically, preferably to implement a Poka-Yoke principle. This prevents assembly errors and thus subsequent rejects.

[0059] One advantage of the integrated control on the first circuit board is that the number of connection lines for the drive unit can be minimized. P45614PC00 / V / V ​​07.08.2025

[0060] 12

[0061] For example, the number of connection lines can be reduced from eleven to five. Furthermore, direct communication via CANopen® according to EN 50325-4:2002 is advantageously enabled. The axial length of the drive unit is also reduced, as no space is required for external control.

[0062] With regard to the stator of the drive unit's motor, it has proven particularly advantageous if, according to a further embodiment, the stator has at least one stator core and at least one insulating cap at at least one end. The insulating cap is aligned with the stator core, for example, by means of at least one continuous recess. Preferably, at least one insulating cap is provided at both opposite ends of the stator core. The opposite ends of the stator are, in particular, those ends that lie in a direction parallel to the rotor's axis of rotation. In the assembled state, the insulating cap is at least partially surrounded by the stator windings.

[0063] Each insulating cap preferably comprises at least or exactly two or at least or exactly three segments, each extending over a portion of the circumference. An insulating cap, in particular, extends over the entire circumference. For example, at least one insulating cap, and especially the segments of an insulating cap, is manufactured using an additive manufacturing process. Preferably, the insulating cap is manufactured, particularly in one piece, by injection molding.

[0064] The insulating cap is preferably designed to completely cover the stator core, including the teeth, at one end. The insulating cap is preferably fully enclosed. The insulating cap is made, for example, of an electrically insulating material, particularly plastic. Advantageously, the insulating cap is made of polyamide, particularly polyamide 12 or polyamide 66, or of acrylonitrile butadiene styrene (ABS). Preferably, the insulating cap is designed as follows: P45614PC00 / V / V ​​07.08.2025

[0065] 13 is designed to have a plurality of projections, each of which penetrates at least partially between two teeth of the stator core. The projections are preferably fully enclosed with a recess for a tooth of the stator core. In particular, the projections are collar-shaped. The projections simplify the positioning of the insulating cap at one end and increase stability.

[0066] In particular, it is provided that a continuous joining gap is formed between each collar-like projection and the space between two teeth. The joining gap is dimensioned such that assembly, i.e., inserting the projections between the teeth, is simplified, while at the same time preventing damage to the insulating cap during winding. A joining gap in the range of 0.3 mm to 0.8 mm, and especially 0.5 mm, has proven advantageous.

[0067] The projections also have the advantage that the insulating cap extends at least partially parallel to the stator teeth, thus simplifying the guidance of the windings during manufacturing. A further advantage of the projections is that they prevent short circuits between the windings and the stator core. Preferably, at least one rib is provided for each tooth of the stator core, extending along an end face of the tooth, as well as a headpiece, which is arranged, in particular, opposite an outer circumferential section. The headpiece is located opposite the circumferential section at the end of the rib. The headpiece is preferably raised above the rib. For example, the headpiece is essentially semicircular, rectangular, or polygonal and raised above a rib, so that the windings can be arranged between an outer circumference and the headpiece.The circumferential section and the head piece thus form a lateral guide for a winding. Two insulating caps arranged opposite each other on a tooth define an end-side P45614PC00 / V / V ​​07.08.2025.

[0068] 14

[0069] Shape of a tooth. The insulating cap is preferably made in one piece or in multiple parts, in particular in three parts.

[0070] According to a further embodiment, it has proven advantageous if the head piece has a larger inner diameter than the corresponding tooth. This positions the head piece slightly recessed relative to the tooth. This recessed position of the head piece relative to the tooth reliably prevents damage to the head piece, particularly breakage, during assembly or winding. Preferably, the inner diameter of the head piece is 0.5 mm to 1 mm larger than the diameter of the teeth.

[0071] The manufacture of the motor for the drive unit can be simplified, in particular, by having the insulating cap have at least one circumferential section, and by having wire guide recesses and / or deflection recesses formed on this circumferential section. The wire guide recesses are, for example, designed as recesses extending radially outwards through the circumferential section. These recesses serve, for example, to guide individual sections of a winding outwards around the circumference, for instance, for connecting a phase. The deflection recesses serve, for example, to deflect a section of a winding to another tooth of the stator. The deflection recesses, for example, have at least two substantially quarter-circular recesses and / or at least or exactly two or at least or exactly three radially oriented recesses.

[0072] In particular, it is provided that the insulating cap has at least one circumferential section, and that at least one clamping device for a winding wire is formed on the circumferential section. Preferably, the clamping device is designed to hold a winding wire by force-fit, form-fit, or force-fit locking. For example, the clamping device has at least one tapered gap or a gap with at least one P45614PC00 / V / V ​​07.08.2025

[0073] 15 or a plurality of clamping projections. In particular, it is provided that a clamping device has a curved or S-shaped gap. In particular, it is provided that the gap is oriented substantially radially to a central axis of the motor. The clamping device in particular prevents the wire tension from causing the winding wire to spring back towards the core.

[0074] Preferably, in the assembled state, at least one circuit board of the electronic unit is mounted on the semicircular end pieces.

[0075] Alternatively or additionally, a plurality of coding elements are arranged on the circumferential section for positive-locking interaction with a printed circuit board. Preferably, at least or exactly two or at least or exactly three coding elements are provided. For example, one coding element is semi-cylindrical. The coding elements engage in corresponding recesses on the printed circuit board and are arranged and designed such that the printed circuit board can only be placed against the insulating cap in a single orientation. In particular, both printed circuit boards interact with the coding elements. This has the advantage that a common tolerance reference point is ensured.

[0076] In particular, when an insulating cap is multi-part, e.g., three-part, it is provided that at least one coding element is formed on each segment. Preferably, an insulating cap is assembled from three segments, two of which are identical, i.e., they have the coding element in the same position, and a third segment has a different position of the coding element. This ensures that a printed circuit board can only be mounted in a specific orientation.

[0077] Preferably, at least one coding element is formed between the housing and the front flange, so that the orientation of the front flange to the housing can be defined. Furthermore, a portion of the torque can be controlled via such a coding element. P45614PC00 / V / V ​​07.08.2025

[0078] 16 are supported. In particular, a plurality of coding elements are provided.

[0079] The drive unit according to the invention has a very short overall length along the rotor's axis of rotation compared to drive units known from the prior art, measuring, for example, between 25 mm and 40 mm, and in particular between 30 mm and 35 mm. Furthermore, the described arrangement of the components and the materials used result in an advantageous temperature distribution, leading to lower temperatures on the outer surfaces.

[0080] A further embodiment of the invention provides that the housing of the drive unit is electrically conductive, and that the housing forms an electrically conductive path from an electrically conductive front flange or an electrically conductive planetary carrier, in particular a first planetary carrier, to a grounding contact of the drive unit, e.g., on a circuit board or a connector or connecting cable. For example, the grounding contact is formed on a connector or connecting cable on a circuit board. The housing is thus part of an electrically conductive path between an electrically conductive front flange or an electrically conductive planetary carrier and a grounding contact of the motor, e.g., on a connector or connecting cable. Such a design allows electromagnetic interference to be dissipated to the ground contact.Preferably, the electrically conductive path is formed at least partially in an external part of the housing. In particular, the electrically conductive path is connected to a shield of at least one connecting cable. According to a further aspect, the invention relates to a motor, in particular for a described drive unit. The motor has a housing, at least one stator with a stator core, and at least one rotor. The rotor is arranged in an inner volume of the stator. The motor is in particular designed as an internal rotor. The motor is characterized in that at least one insulating cap according to one of P45614PC00 / V / V ​​07.08.2025 is provided on opposite end faces of the stator core.

[0081] The insulating caps are arranged as described in the embodiments described in Section 17. They particularly preferably have the described end sections with a web and a head. Advantageously, each insulating cap also has the projections. For example, a rotor pole wheel has a bell shape. The motor is preferably designed with the features or partial features of a motor that have been described in connection with the drive unit for the motor and, in particular, in claims 2 to 14. An output element of the motor is, for example, formed directly by a shaft of the rotor, e.g., a hollow shaft, or connected to the shaft of the rotor.

[0082] Alternatively, the motor is characterized in that a rotor pole wheel has a bearing element for a plurality of magnets formed integrally with the pole wheel. In particular, the pole wheel and bearing element are manufactured by sintering or an additive manufacturing process, e.g., by selective laser melting (SLM) / direct metal laser melting (DMLS), electron beam melting (EBM), direct energy deposition (DED), binder jetting, metal extrusion / bound metal deposition (BMD), ultrasonic additive manufacturing (UAM), or material jetting. In particular, the bearing element is designed as a bearing ring formed integrally with the pole wheel. The bearing ring preferably has a number of recesses corresponding to the number of magnets. The shape of a recess essentially corresponds to the outer shape of a magnet. Preferably, a rotor pole wheel has a bell shape.The motor is preferably designed with the features or partial features of a motor that have been described in connection with the drive unit for the motor and in claims 2 to 14. An output element of the motor is, for example, formed directly by a shaft of the rotor, e.g., a hollow shaft, or connected to the shaft of the rotor.

[0083] Further advantageous embodiments of the invention will become apparent from the following description of the figures and the dependent subclaims.

[0084] It shows: P45614PC00 / V / V ​​07.08.2025

[0085] 18

[0086] Fig. 1 shows an embodiment of a drive unit in perspective view,

[0087] Fig. 2 shows the embodiment of Fig. 1 in exploded view,

[0088] Fig. 3 shows the embodiment of Figs. 1 and 2 in a section through the

[0089] Rotational axis of the rotor,

[0090] Fig. 4 shows an embodiment of a gear unit in exploded view,

[0091] Figs. 5a, 5b show an embodiment of an insulating cap,

[0092] Fig. 6 shows an embodiment of another drive unit without a gearbox,

[0093] Fig. 7 shows an embodiment of a gearbox for a drive unit in a section view.

[0094] Fig. 8 shows an exploded view of part of the stator,

[0095] Figs. 9a, 9b show an embodiment of part of a stator, and

[0096] Fig. 10 shows an embodiment of a segment of an insulating cap.

[0097] In the various figures of the drawing, identical parts are always labelled with the same reference symbols.

[0098] The following description claims that the invention is not limited to the exemplary embodiments and not to all or several features of the described combinations of features; rather, each individual partial feature of the exemplary embodiment(s) is also independent of all other partial features described in connection therewith, both on its own and also in P45614PC00 / V / V ​​07.08.2025

[0099] 19

[0100] Combination with any features of another embodiment relevant to the subject matter of the invention.

[0101] Fig. 1 shows an embodiment of a drive unit 1 in a perspective view. The drive unit 1 comprises a motor 2 and a gearbox 3. The motor

[0102] 2 and the gearbox 3 are arranged in a housing 4 of the drive unit 1. The housing 4 has a front flange 5 and a back plate 6 (see Fig. 2). The back plate 6 has a feedthrough 59 for the connecting cables 56 of the drive unit 1. The connecting cables 56 are secured with a strain relief 60. In this embodiment, the front flange 5 has a pulley 5a which is integrally connected to the front flange 5.

[0103] Fig. 2 shows an exploded view of the embodiment of Fig. 1 with an additional pulley 57, which is rotatably connected to an output element 13 of the drive unit 1. Alternatively, the pulley 57 is designed as part of the output element 13. Fig. 3 shows the drive unit 1 according to Fig. 2 in a section through a rotation axis R of the rotor 8. The motor 2 has a stator 7 and a rotor 8, as shown in Figs. 2 and 3. The motor 2 is designed as an internal rotor, and the rotor 8 has an internal volume 9 in which the gearbox 3 is at least partially arranged. The gearbox 3 is designed as a gearbox unit arranged in a gearbox housing 10. In this embodiment, the gearbox 3 is designed as a single-stage planetary gearbox with stepped planet gears 11 – see, for example, Fig. 4.

[0104] The gear unit 3, designed as a planetary gear unit, has, according to Figs. 3 and 4, a first planet carrier 12, which simultaneously forms the output element 13 of the gear unit.

[0105] 3. The first planet carrier 12 is mounted on an inner surface 16 of the gearbox housing 10 by means of a ball bearing 14. The ball bearing 14 rests axially against a shoulder 15. The inner surface 16 is the circumferential inner surface of the gearbox housing 10. The gearbox 3 – see also Fig. 4 – is completely enclosed in the gearbox housing 10 and therefore forms a modular gearbox unit. P45614PC00 / V / V ​​07.08.2025

[0106] 20

[0107] The gearbox 3 has a second planet carrier 17, which is oriented towards the rear of the drive unit 1, specifically opposite the output element 13 and the first planet carrier 12. The second planet carrier 17 is supported by a ball bearing 18 on the inside 16 of the gearbox housing 10. The rotor 8 is also supported by a ball bearing 19 on a projection 20 in the second planet carrier 17. The rotor shaft 22 is inserted into the projection 20 and supported on the opposite side by a ball bearing 21 in the first planet carrier 12.

[0108] The gearbox 3 has a ring gear 23 that engages positively with the gearbox housing 10. For this purpose, a pin 24 is provided which engages in a first groove 25 on the gearbox housing 10 and a second groove 26 on the ring gear 23.

[0109] The three stepped planet gears 11 are mounted on pins 28 by means of needle bearings 27. For example, the pins 28 are welded to the planet carriers 12, 17. In particular, the pins 28, when welded, exert a preload on the ball bearings 14, 18. Preferably, the needle bearings 27 have only an outer ring and a needle race to achieve a low radial height. The planet gears 11 interact with a pinion 29 attached to the rotor shaft 22. The gearbox housing 10 is surrounded by a pole wheel 30 of the rotor 8. The projection 20 is also formed on the pole wheel 30. The pole wheel 30 has a back section 31 in which a plurality of polygonal recesses 32 are arranged for weight reduction, in particular for reducing the moment of inertia. The back section 31 of the pole wheel 30 extends essentially orthogonally to the axis of rotation R of the rotor 8.

[0110] The pole wheel 30 has a recess 33 for an encoder magnet 34. The recess 33 for the encoder magnet 34 is arranged coaxially with the rotor shaft 22. Furthermore, the pole wheel 30 has a section 35, which is located in P45614PC00 / V / V ​​07.08.2025

[0111] 21

[0112] The section 35 extends essentially parallel to the axis of rotation R and defines the internal volume 9 of the rotor 8. The pole wheel 30 is essentially bell-shaped. The majority of the magnets 36 of the rotor 8 are arranged on an outer circumference of the section 35. Each magnet 36 is arranged in a recess 37 of a bearing cage 38. The bearing cage 38 is arranged on the section 35 and completely surrounds the pole wheel 30.

[0113] The drive unit 1 also includes an electronics unit 39. The electronics unit 39 is mounted on the stator 7 and comprises a first circuit board 40 and a second circuit board 41. The first circuit board 40 and the second circuit board 41 are arranged one above the other and electrically connected by means of solder joints (see especially Fig. 3). The second circuit board 41 is ring-shaped and serves for contacting and connecting the motor phases (see, for example, Fig. 9b). The encoder chip 42, corresponding to the encoder magnet 34, with integrated Hall sensors, is arranged on the first circuit board 40. A motor controller is also arranged on the first circuit board 40.

[0114] The stator 7 has a stator core 43, as shown in Figures 2 and 3. An insulating cap 44 is arranged at each of the opposite end faces of the stator core 43, shown separately in Figures 5a and 5b. Figure 5a shows an insulating cap 44 from the top, and Figure 5b from the bottom. In the assembled state, as shown in Figure 2, the insulating caps 44 are at least partially separated from the windings.

[0115] 45 of the stator 7 are surrounded. Each insulating cap 44 has one of the number of teeth.

[0116] 46 corresponding number of end elements 47. Each end element 47 covers a tooth 46 face. An end element 47 extends radially inwards from a circumferential section 52 of the insulating cap 44.

[0117] Each end element 47 comprises a web 48 and a head piece 49. The head piece 49 is essentially semicircular. In a direction parallel to the axis of rotation R, the head piece 49 has an extent that corresponds approximately to the extent of the circumferential section 52. The web 48 has a smaller extent. P45614PC00 / V / V ​​07.08.2025

[0118] 22 axial extension, so that the head piece 49 and the circumferential section 52 guide or limit a winding 45 on a bridge 48 or on a tooth 46.

[0119] The web 48 and the head piece 49 each cover an end face of an associated tooth 46 in the axial direction parallel to the axis of rotation R. In addition, each insulating cap 44 has a plurality of collar-like projections 50, each of which penetrates between two teeth 46 of the stator core 43. Each projection 50 runs parallel to a side edge of a web 48 and is closed at the circumferential section 52 between two teeth 46. Each projection 50 has two protective projections 51 extending away from a tooth 46, which extend at least partially below the head piece 49 parallel to the axis of rotation R. A tooth 46 passes radially between each of the protective projections 51.

[0120] Each insulating cap 44 has a circumferential section 52 that includes both wire guide recesses 53 and deflection recesses 54. The wire guide recesses 53 serve to radially guide the winding wire out, for example, to connect a phase. The deflection recesses 54, which are essentially arc-shaped, serve to deflect the winding wire to another tooth 46. Furthermore, each circumferential section 52 has three semi-cylindrical coding elements 55 that serve to position the first circuit board 40 and the second circuit board 41. As shown in Fig. 2, the first circuit board 40 has a number of recesses 58 corresponding to the number of coding elements 55 – here three – which interact positively with the coding elements 55 and define the orientation of the first circuit board 40.

[0121] In an alternative embodiment, also designed according to Fig. 3, the housing 4 of the drive unit 3 is electrically conductive, so that an electrically conductive path is realized with the housing 4 from an electrically conductive pulley 57 and / or an electrically conductive first planetary carrier 12 to a grounding contact of the drive unit 1, e.g. on a circuit board 40, 41 and / or a connecting cable 56. As an alternative to the pulley 57, P45614PC00 / V / V ​​07.08.2025

[0122] 23. An electrically conductive output element may also be present. For example, an electrically conductive path is formed from the pulley 57 or a connecting flange to the conductive first planet carrier 17 and from there to the gearbox housing 10, further to the housing 4 of the drive unit and from there to a grounding contact on a circuit board 40, 41 and / or a connecting cable 56. For example, ball bearings 15, 18 with electrically conductive bearing grease are used.

[0123] Alternatively, it is also provided in particular that a sliding contact is arranged between the pulley 57 or output element and the housing 4 in order to form an electrically conductive path to the housing 4 and from there to the grounding contact.

[0124] Fig. 6 shows an alternative embodiment of a drive unit 1 in a section through the axis of rotation R. In this embodiment, the drive unit has no gearbox. The motor 2 is designed as a hollow shaft motor. The stator 7 of the motor 2 is designed as described for the preceding embodiments. In particular, the stator 7 has two insulating caps 44 arranged on the opposite end faces of the stator core 43, which are designed as shown in Figs. 5a and 5b. In the assembled state according to Fig. 6, the insulating caps 44 are at least partially surrounded by the windings 45 of the stator 7. Each insulating cap 44 has a number of end elements 47 corresponding to the number of teeth 46. Each end element 47 covers one tooth 46 at its end face. An end element 47 extends radially inwards from a circumferential section 52 of the insulating cap 44 (see also Figs. 5a and 5b).

[0125] The electronic unit 39 comprises a first circuit board 40 and a second circuit board 41. The second circuit board 41 is also mounted on the end pieces 49 of the insulating cap 44 (see Figs. 5a and 5b). The strain relief 60 and the connecting leads 56 are not shown in Fig. 6. The housing 4 of the drive unit 1 is formed by a front flange 5 and a back plate 6. P45614PC00 / V / V ​​07.08.2025

[0126] 24 closed. In this embodiment, the front flange 5 has a support projection 61 that extends into the pole wheel 30 of the rotor 8. The rotor 8 is mounted in the front flange 5 and the support projection 61, respectively, by means of ball bearings 14, 18, via a hollow shaft 62. The pole wheel 30 is formed integrally with the hollow shaft 62. The hollow shaft 62 forms the output element 13 of the drive unit 1.

[0127] Furthermore, the pole wheel 30 has a section 35 that extends essentially parallel to the axis of rotation R. The pole wheel 30 is essentially bell-shaped. The majority of the magnets 36 of the rotor 8 are arranged on an outer circumference of the section 35. Each magnet 36 is arranged in a recess 37 of a bearing cage 38. The bearing cage 38 is arranged on the section 35 and completely surrounds the pole wheel 30.

[0128] Fig. 7 shows an embodiment of a gearbox 3 in a section, for example for a drive unit 1 according to Fig. 1. In this embodiment, the gearbox housing 1 is formed integrally with the ring gear 23. Alternatively, a two-part design with a dividing plane is also provided, the dividing plane of which has the axis of rotation R as its normal plane. In this case, the ring gear is formed integrally with, for example, a rear housing part, shown on the left in Fig. 7.

[0129] The gear unit 3, designed as a planetary gear, has, as shown in Fig. 7, a first planet carrier 12, which simultaneously forms the output element 13 of the gear unit 3. The first planet carrier 12 is mounted by a ball bearing 14 on an inner surface 16 of the gear housing 10. The ball bearing 14 bears axially against a shoulder 15 that adjoins the ring gear 23. The inner surface 16 is a circumferential surface of the gear housing 10. The gear unit 3 is completely enclosed within the gear housing 10 and therefore forms a modular gear unit.

[0130] The gearbox 3 has a second planet carrier 17, which points in the direction of the

[0131] Rear side of drive unit 1, in particular opposite to P45614PC00 / V / V ​​07.08.2025

[0132] 25

[0133] The output element 13 is oriented towards the first planet carrier 12. The second planet carrier 17 is mounted on the inside 16 of the gearbox housing 10 by means of a ball bearing 18.

[0134] The three stepped planet gears 11 are mounted on pins 28 by means of needle bearings 27. Preferably, the needle bearings 27 have only an outer ring and a needle race to achieve a low radial height. The first planet carrier 12 and the second planet carrier 17 are detachably connected to each other by a plurality of screws 66, here three screws 66. This allows the gearbox 3 to be disassembled advantageously without damage. Each screw 66 is surrounded by a spacer sleeve 67. The spacer sleeves 67 protect the screws 66, in particular from the negative effects of the gearbox grease. Depending on the design of the spacer sleeves 67, they can define the exact axial distance between the planet carriers 12, 17 or, if designed to be slightly shorter axially, they define the maximum preload on the ball bearings 14, 18.

[0135] Fig. 8 shows an embodiment of a part of a stator 7, namely a wound stator core 43 for a drive unit, e.g., according to Fig. 1, in an exploded view. The windings 45 surround the stator core 43 and the insulating caps 44 arranged on both opposite end faces of the stator core 43 and partially inserted into the stator core. The windings 45 have a plurality of taps 63 which are contacted or connected on a printed circuit board 41 (see Fig. 9b). At least one of the insulating caps 44 has coding elements 55 which serve to align at least one printed circuit board 40, 41 and, if present, both printed circuit boards 40, 41.

[0136] Figures 9a and 9b show an embodiment of a part of a stator 7, namely a wound and interconnected laminated core in a section and a top view. The windings 45 or coils of the stator 7 surround the teeth 46 and the two end-mounted insulating caps 44. In this embodiment, the insulating caps 44 are each formed in one piece. The circuit board 41 for interconnecting the windings 45 rests on the semicircular end pieces 49 of one of the P45614PC00 / V / V ​​07.08.2025

[0137] 26

[0138] Insulating caps 44 are attached. Fig. 9b shows a top view of the printed circuit board 41. The taps 63 of the windings 45 are guided through U-shaped grooves 64 onto the surface of the printed circuit board 41 facing away from the windings 45 and folded onto the surface. The grooves 64 protect the winding wire, in particular from mechanical impacts from a radial direction. Contact is made by soldering the taps 63 to solder pads 65 on the printed circuit board 41. This significantly simplifies the wiring of the windings 45 and allows it to be automated. This is particularly advantageous for high-pole internal rotor motors.

[0139] Fig. 10 shows an embodiment of a segment 44a of an insulating cap 44, which in its assembled state consists of three segments 44a. The segment 44a is manufactured, for example, by an additive manufacturing process. The circumferential section 52 has wire guide recesses 53 and deflection recesses 54. The wire guide recesses 53 serve, in particular, for the radial routing of the winding wire, for example, to a tap 63 for connecting a phase. The deflection recesses 54, which are essentially arc-shaped, serve to deflect the winding wire to a further tooth 46. The wire deflection recesses 54 each have a clamping device 54a, which serves to mechanically clamp the winding wire. For this purpose, the clamping device 54a is designed, for example, as a tapered gap into which the winding wire can be clamped. This advantageously prevents the winding wire from springing back.

[0140] In this embodiment, the inner diameter at the end faces of the head pieces 49 is dimensioned to be slightly larger than the inner diameter of a tooth 46, thus preventing damage to the insulating cap 44 during assembly and when winding the teeth 46 with the insulating caps 44 already mounted. The projections 50 are dimensioned to form a circumferential gap of approximately 0.5 mm between the teeth 46. This ensures reliable assembly and, within the tolerances, prevents the insulating cap 44 from jamming. P45614PC00 / V / V ​​07.08.2025

[0141] 27

[0142] The invention is not limited to the embodiments illustrated and described, but also encompasses all embodiments that have the same effect within the meaning of the invention. It is expressly emphasized that the embodiments are not limited to all features in combination; rather, each individual feature can also have inventive significance independently of all other features. Furthermore, the invention is not yet limited to the combination of features defined in claim 1, but can also be defined by any other combination of specific features from all disclosed individual features. This means that, in principle, virtually any individual feature of claim 1 can be omitted or replaced by at least one individual feature disclosed elsewhere in the application.

[0143] P45614PC00 / V / V ​​07.08.2025

[0144] 28

[0145] List of reference signs

[0146] 1 drive unit

[0147] 2 Engine

[0148] 3 gearboxes

[0149] 4 cases

[0150] 5 Front flange

[0151] 5a Pulley

[0152] 6 Backplate

[0153] 7 Stator

[0154] 8 Rotor

[0155] 9 internal volume

[0156] 10 Gearbox housings

[0157] 11 planetary gear

[0158] 12 First planetary carrier

[0159] 13 Output element

[0160] 14 ball bearings

[0161] Paragraph 15

[0162] 16 Inside

[0163] 17 Second planetary carrier

[0164] 18 ball bearings

[0165] 19 ball bearings

[0166] 20 Approach

[0167] 21 ball bearings

[0168] 22 Rotor shaft

[0169] 23 Ring gear

[0170] 24 pens

[0171] 25 First Nut

[0172] 26 Second groove

[0173] 27 nail bearings

[0174] 28 pens

[0175] 29 Pinion P45614PC00 / V / V ​​07.08.2025

[0176] 30 flywheel

[0177] 31 Back area

[0178] 32 Exclusion

[0179] 33 Exclusion

[0180] 34 Encoder magnet

[0181] Section 35

[0182] 36 Magnet

[0183] 37 Exclusion

[0184] 38 bearing cage

[0185] 39 Electronic unit

[0186] 40 First circuit board

[0187] 41 Second circuit board

[0188] 42 Encoder chip

[0189] 43 Stator core

[0190] 44 Insulating cap

[0191] 44a Segment

[0192] 45 windings

[0193] 46 teeth

[0194] 47 End element

[0195] 48 Bridge

[0196] 49 Headpiece

[0197] 50 lead

[0198] 51 Protective projection

[0199] 52 Scope section

[0200] 53 Wire guide return

[0201] 54 Redirect jump

[0202] 54a Clamping device

[0203] 55 Coding element

[0204] 56 connecting lines

[0205] 57 Pulley

[0206] 58 Exclusion

[0207] 59 Implementation P45614PC00 / V / V ​​07.08.2025

[0208] 30

[0209] 60 Strain relief

[0210] 61 Supporting projection

[0211] 62 Hollow shaft

[0212] 63 taps

[0213] 64 Nut

[0214] 65 soldering surface

[0215] 66 screws

[0216] 67 Spacer sleeve

[0217] R Rotation axis of the rotor

Claims

P45614PC00 / V / V ​​07.08.2025 31 Claims 1. Drive unit (1) comprising at least one motor (2), at least one gearbox (3) and at least one housing (4), wherein the motor (2) comprises at least one stator (7) and at least one rotor (8), and wherein the gearbox (3) is arranged at least partially in an internal volume (9) of the rotor (8), characterized in that the gearbox (3) is designed as a gearbox unit arranged in a gearbox housing (10).

2. Drive unit (1) according to claim 1, characterized in that the transmission (3) is designed as a, preferably single-stage, planetary transmission, in particular as a planetary transmission with stepped planet gears (11).

3. Drive unit (1 ) according to claim 1 or 2, characterized in that the planetary gear has at least one first planet carrier (12, 13), and that the first planet carrier (12) is mounted on an inner side (16) of the gear housing (10), in particular that the planetary gear has at least one second planet carrier (17), and that the second planet carrier is mounted on an inner side (16) of the gear housing (10).

4. Drive unit (1) according to one of claims 1 to 3, characterized in that the transmission (3) has at least one ring gear (23), and that the ring gear (23) is formed integrally with the transmission housing (4), or that the transmission (3) has at least one ring gear (23), and that the ring gear (23) interacts positively with the transmission housing (10), in particular that at least one positive locking element, for example a pin (24), P45614PC00 / V / V ​​07.08.2025 32 is present, which engages in a first groove (25) on the gearbox housing (10) and in a second groove (26) on the ring gear (23).

5. Drive unit (1 ) according to one of claims 2 to 4, characterized in that the planet gears (11 ) of the planetary gear are mounted by means of needle bearings (27), in particular that a needle bearing (27) has at least one outer sleeve and at least one needle ring.

6. Drive unit (1 ) according to one of claims 1 to 5, characterized in that the rotor (8) has at least one pole wheel (30), that the pole wheel (30) has at least one back section (31 ), and that the back section (31 ) has at least one recess (32) for weight reduction, preferably that a plurality of polygonal or circular recesses (32) are provided.

7. Drive unit (1) according to one of claims 1 to 6, characterized in that the rotor (8) has at least one recess (33) for an encoder magnet (34), in particular that the recess (33) is formed in a pole wheel (30) of the rotor (8), 8. Drive unit (1 ) according to one of claims 1 to 7, characterized in that the rotor (8) has a plurality of magnets (36), and that the magnets (36) are arranged in a bearing cage (38), in particular that the bearing cage (36) surrounds a pole wheel (30) of the rotor (8), or that the rotor (8) has a plurality of magnets (36), and that the magnets (36) are each arranged on separate, substantially planar, surfaces on an outer circumference of the pole wheel (30). P45614PC00 / V / V ​​07.08.2025 33 9. Drive unit (1 ) according to one of claims 1 to 8, characterized in that an electronic unit (39) is mounted on the stator (7), in particular that the electronic unit (39) is arranged in the housing (4), preferably that the electronic unit (39) has at least one motor controller and / or at least one sensor (42), preferably at least one Hall sensor or encoder chip with Hall sensor.

10. Drive unit (1 ) according to one of claims 1 to 9, characterized in that the stator (7) has at least one stator core (43), and that the stator core (43) has at least one insulating cap (44) at at least one end side, in particular that the insulating cap (44) penetrates at least partially into the stator core (43) between two teeth (46) of the stator core (43).

11. Drive unit (1) according to claim 10, characterized in that the insulating cap (44) has a number of end elements (47) corresponding to the number of teeth (46), and that each end element (47) covers a corresponding tooth (46) in its end region.

12. Drive unit (1 ) according to claim 11 , characterized in that each end element (47) has at least one web (48) and at least one head piece (49), in particular that the head piece (49) is semicircular.

13. Drive unit (1) according to one of claims 10 to 12, characterized in that P45614PC00 / V / V ​​07.08.2025 34 the insulating cap (44) has a circumferential section (52), and that wire guide recesses (53) and / or deflection recesses (54) are formed on the circumferential section (52).

14. Drive unit (1 ) according to one of claims 10 to 13, characterized in that the insulating cap (44) has a circumferential section (52) and that a plurality of coding elements (55) are arranged on the circumferential section (52) for positive interlocking interaction with a printed circuit board (40,41 ).

15. Drive unit (1) comprising at least one motor (2) and at least one housing (4), wherein the motor (2) comprises at least one stator (7) and at least one rotor (8), wherein the rotor (8) is arranged in an inner volume of the stator (7), characterized in that the stator (8) comprises at least one stator core (43), that at least one insulating cap (44) is arranged on opposite end faces of the stator core (43), that each insulating cap (44) has a plurality of collar-like projections (50), and that each collar-like projection between two teeth (46) of the stator core (43) penetrates at least partially into the stator core (43), in particular characterized by the feature content of at least one claim of claims 6 to 14.

16. Drive unit (1) comprising at least one motor (2) and at least one housing (4), wherein the motor (2) comprises at least one stator (7) and at least one rotor (8), wherein the rotor (8) is arranged in an inner volume of the stator (7), characterized in that the rotor (8) comprises at least one pole wheel (30), and that the pole wheel (30) comprises bearing means formed integrally with the pole wheel, in particular a bearing cage (38) for a plurality of magnets (36), in particular P45614PC00 / V / V ​​07.08.2025 35 formed by the feature content of at least one claim of claims 6 to 14.

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