Brake unit for a force-feedback system, force-feedback system having a brake unit, and steering mechanism having a force-feedback system

Abstract

The invention relates to a brake unit (1) for a force-feedback system (30) for a steering mechanism (50), in particular a steer-by-wire steering mechanism, of a vehicle, the brake unit comprising: an annular stator (2), which has a coil-receiving portion (5); a coil (4), which is arranged in the coil-receiving portion (5) of the stator (2); a hollow-cylindrical rotor (3), which is arranged radially outside the stator (2) and the coil (4) such that a gap (6) is formed between the stator (2) and the rotor (3), wherein the rotor (3) can be rotated relative to the stator (2); a casing means (11), which is designed to enclose the stator (2) and the coil (4), wherein the casing means (11) is formed by annular side walls (9), which are arranged, in the axial direction (A), on either side of the stator (2), and by the rotor (3), which is coupled to the side walls (9) for conjoint rotation; at least two sealing devices (13), which are designed to seal off an inner chamber (12), formed by the casing means (11), from the outside; and wherein the stator (2) comprises a radially and / or axially extending passage opening (16), which is designed to expose electrical contacts (14) of the coil (4). The invention also relates to a force-feedback system (30) having such a brake unit (1), and to a steering mechanism (50) having such a force-feedback system (30).

Description

[0001] Brake unit for force feedback system, force feedback system with brake unit and steering device with force feedback system

[0002] The present invention relates to a brake unit for a force feedback system for a steering device, in particular a steer-by-wire steering device, of a vehicle, a force feedback system for a steering device, in particular a steer-by-wire steering device, of a vehicle and a steering device, in particular a steer-by-wire steering device, of a vehicle.

[0003] State of the art

[0004] Today, both mechanical steering systems and so-called steer-by-wire steering systems are known. Steering systems can be divided into two subsystems: the steering shaft system with a steering element, such as a steering wheel, also known as a "hand wheel actuator" (HWA) system, and the steering actuator system for steering the wheels, also known as a "road wheel actuator" (RWA) system. In mechanical steering systems, these two subsystems are mechanically connected via the steering column and, if necessary, a steering gear. Thus, in mechanical steering systems, the two subsystems are directly, i.e., physically, connected. Thus, when operating the steering element in mechanical steering systems, a user or operator always experiences a noticeable resonance, so-called force feedback, in the form of noticeable resistance at the steering element, especially when cornering, hitting curbs, etc.

[0005] In steer-by-wire steering systems, the mechanical connection between the two subsystems via the steering column is dispensed with, and the steering of the wheels in response to movement of the steering element is controlled by transmitting corresponding signals between the two subsystems HWA and RWA. In other words, with steer-by-wire steering systems, the physical steering column, which transmits the "input signals" or driver commands from the steering wheel directly via the steering gear, tie rod and wheel carrier to the wheel, is replaced by electrically redundant "by wire", i.e. signal transmission via cable. Inversely, in line with the signal transmission from the driver to the wheels, the driver also needs information or feedback, the so-called force feedback, from the wheels to the steering wheel. Force feedback systems, e.g. force feedback actuators, are currently commonly used for this.which makes the (steering) restoring torques perceptible to the driver via the steering element on a mechatronic basis. Furthermore, two types of steer-by-wire steering systems can be distinguished: steer-by-wire steering systems with a force feedback system remote from the steering element, e.g., the steering wheel, and steer-by-wire steering systems with a force feedback system close to the steering element, e.g., the steering wheel.

[0006] The force feedback systems are integrated into the subsystem of the steering shaft, i.e. the HWA system, whereby the systems currently usually comprise a drive unit, in particular an electric motor, and a brake unit, which are electronically controlled according to the desired force feedback, see for example WO 2022 / 170050 A1 , and WO 2019 / 042531 A1. The electric motors are usually designed as so-called

[0007] "Internal rotor" design, meaning the rotor is located inside the stator. Force feedback systems with a so-called "external rotor" electric motor, meaning an electric motor in which the rotor is located outside the stator, are also known (see, for example, EP 3 960 582 A1), but without a braking unit.

[0008] It has now emerged that there is a further need to improve a known brake unit for a force feedback system, in particular for a force feedback system close to the steering element for a steering device, in particular a steer-by-wire steering device, of a vehicle. In particular, there is a further need to provide a brake unit for a force feedback system, in particular for a force feedback system close to the steering element, with an annular installation space that enables improved braking torque and / or improves manufacturability and robustness and / or reduces the required installation space.

[0009] Against this background, it is an object of the present invention to provide an improved brake unit for a force feedback system, in particular a force feedback system close to the steering element, for a steering device, in particular a steer-by-wire steering device, of a vehicle, which in particular enables an improved braking torque and / or improves manufacturability and robustness and / or reduces the required installation space.

[0010] Disclosure of the invention

[0011] These and other objects, which will be mentioned upon reading the following description or which may be recognized by a person skilled in the art, are achieved by the subject matter of the independent claims. Advantageous embodiments and further developments can be found in the subclaims and the following description. The brake unit according to the invention for a force feedback system for a steering device, in particular a steer-by-wire steering device, of a vehicle has a stator, a coil, a rotor, a casing device and at least two sealing devices. The stator is annular and has a coil receiving section. The coil is arranged in the coil receiving section of the stator. The rotor is hollow-cylindrical and is arranged radially outside the stator and the coil such that a gap is formed between the stator and the rotor, wherein the rotor is rotatable relative to the stator.The enclosing device is configured to enclose the stator and the coil, wherein the enclosing device is formed by annular side walls arranged in the axial direction on both sides of the stator, and the rotor, which is coupled to the side walls in a rotationally fixed manner. The at least two sealing devices are configured to seal a housing space formed by the housing section from the outside. The stator has a radially and / or axially extending passage opening configured to expose electrical contacts of the coil.

[0012] One could therefore say that the brake unit is designed as an annular, particularly bearingless, external rotor brake unit. An external rotor brake unit is a brake unit that has a stator and a rotor, with the stationary stator arranged radially inside the rotating rotor.

[0013] The advantage of the solution according to the invention lies in particular in the fact that the brake unit forms a closed and sealed unit that can be assembled and tested as a standalone unit. The brake unit is compact and thus requires comparatively little installation space. Furthermore, the preassembled brake unit can be easily and simply integrated or installed into a force feedback system for a vehicle's steering system. In particular, the brake unit can be easily integrated into an annular installation space of a force feedback system, in particular a force feedback system close to the steering wheel.

[0014] The rotor is made, in particular, of a ferrous material. The annular side walls, which are coupled to the rotor in a rotationally fixed manner, are made, in particular, of a non-magnetic material in order to prevent interaction between the rotor or stator of the brake unit and external, in particular magnetic, components and / or units. The non-magnetic material of the annular side walls can be, for example, a plastic, aluminum, or another non-ferrous metal that is, in particular, easily formable. The term "plastic" here encompasses single-variety plastics, plastic mixtures, as well as fiber-reinforced single-variety plastics and fiber-reinforced plastic mixtures. In particular, the annular side walls are further designed to support the sealing devices. The sealing devices are designed, for example, as quad rings or V-seals or vulcanized sealing lips.

[0015] The enclosing device is formed from the annular side walls and the rotor, and thus rotates relative to the stator during operation. The annular side walls are coupled to the rotor in a rotationally fixed manner, in particular by means of connections created by forming, e.g., flanging, knurling, pressing, etc. In particular, the annular side walls can also be disc-shaped and / or have a collar, a flange, etc.

[0016] Both the rotor and the stator are, in particular, hollow-cylindrical in design. Alternatively, it is also conceivable for the rotor and / or the stator to have non-cylindrical contours, for example, by having teeth, i.e., a tooth-shaped design, interrupted cylindrical surfaces, circumferential grooves, etc.

[0017] According to one embodiment, the stator is designed as a single or multi-part assembly. The single-part stator can reduce the assembly steps required for assembling the brake unit and, due to its seamless, single-part design, has low magnetic resistance. The multi-part, in particular two-part, stator is particularly simple and cost-effective to manufacture and can simplify the assembly process of the brake unit, particularly with regard to the installation of the coil within the stator.

[0018] According to one embodiment, the gap between the stator and the rotor is designed as a cylindrical shear gap that is configured to receive a medium / be filled with a medium. One can therefore say that the gap between the stator and the rotor is designed as a radial gap. Alternatively, it is also conceivable for the gap to be designed as an L-shaped or a U-shaped shear gap. The shear gap extends not only radially between the stator and the rotor, but also axially between at least one end face of the stator or rotor and the corresponding annular side wall. Due to the rotation of the rotor relative to the stator, a shear stress is generated by the medium in the shear gap, depending on the viscosity of the medium, which shear stress acts like a braking torque against the direction of rotation of the rotor with regard to the rotation of the rotor relative to the stator.In particular, the shear gap is located on the largest possible diameter on an inner side of the rotor and radially outside the coil.

[0019] The medium is filled into the shear gap, particularly after assembly of the brake unit, e.g., via appropriately provided filling openings. The filling openings are, in particular, resealable and, when closed, sealed in such a way that the medium cannot escape from the shear gap via the filling openings.

[0020] According to one embodiment, the medium has magnetorheological properties. In particular, the medium is a magnetorheological powder or a magnetorheological fluid. If a medium with magnetorheological properties is subjected to a magnetic field, the viscosity of the medium can be reversibly changed depending on the magnetic field strength. This means that when a magnetic field is applied, a reversible change in the viscosity or viscoelastic properties of the medium can be achieved, which is related to the magnetic field strength. Thus, a desired braking torque can be generated by the braking unit by influencing the viscoelastic properties of the medium located in the shear gap via the magnetic field strength of a magnetic field generated by the rotation of the rotor relative to the stator.

[0021] According to one embodiment, the electrical contacts of the coil are designed as pins and / or blades and / or as cable contact terminals. Designing the electrical contacts as contact blades and / or contact pins can simplify the electrical coupling of the coil. Furthermore, the assembly of the coil in the stator can be simplified with electrical contacts designed as contact blades and / or contact pins, since the particularly costly manual threading of cable tails can be dispensed with.

[0022] According to one embodiment, the coil is accommodated in an annular carrier. The carrier can improve handling of the coil, particularly during assembly. According to one embodiment, the coil and the annular carrier are formed integrally in one piece. For example, the annular carrier can comprise a plastic or be formed from a plastic, with the coil being encapsulated in the plastic. Furthermore, it is conceivable to wrap the coil with a thin metal rim or a metal wire before it is accommodated in the annular carrier. According to one embodiment, the sealing devices are each arranged on a sealing seat that extends in the axial direction, with the sealing seat(s) being formed integrally in one piece with the side wall(s), or with the sealing seat(s) being formed integrally in one piece with the stator.If the sealing seats are formed integrally with the side walls, the sealing devices are carried by the side walls. Since the side walls rotate together with the rotor relative to the stator, in this case the sealing device also rotates relative to the stator. If the sealing seats are formed integrally with the stator, the sealing devices do not rotate. Therefore, in this case the sealing devices in particular have sealing lips which slide against a, in particular non-magnetic component, e.g. the side walls, and thus seal the enclosure device to the outside. The sealing devices can be positively connected, e.g. by means of tooth-like or non-circular features, and / or frictionally connected, e.g. pressed radially between annular surfaces or pressed over shoulders, and / or materially connected, e.g. vulcanized, coupled to or fastened to the stator.

[0023] According to one embodiment, the stator is configured to be coupled in a form-fitting and / or force-fitting manner and / or by material bonding to a stationary element, in particular a cylindrical or hollow-cylindrical support component, which can also be referred to as an axle. For example, the stator can be positively engaged with the stationary element via correspondingly coordinated geometries. Additionally, or alternatively, the stator can be non-positively attached to the stationary element, for example by means of a press fit, screw connections, rivet connections, etc. Further additionally, or alternatively, the stator can be glued, welded, etc. to the stationary element.

[0024] A further aspect of the invention relates to a force feedback system for a steering device, in particular a steer-by-wire steering device, of a vehicle. The force feedback system comprises a brake unit, as described above and below, in particular according to the invention, and an electric motor. The electric motor has a stationary stator and a rotor that is rotatable relative to the stator and arranged radially outside the stator. The brake unit and the electric motor are arranged coaxially and adjacent to one another in the axial direction.

[0025] This coaxial and axially adjacent arrangement of the brake unit and the electric motor enables a compact and thus small-sized force feedback system, which can be installed in a steering system in a space-saving manner and, in particular, close to the steering element. The electric motor is designed as an external rotor electric motor. In particular, it is conceivable for the rotor of the brake unit and the rotor of the electric motor to be formed separately from one another or as an integral part.

[0026] In particular, the brake unit is designed such that it can generate a torque of approximately 5 Nm to approximately 30 Nm, in particular approximately 10 Nm to approximately 20 Nm. Thus, the brake unit can generate at least approximately the same, and in particular even a higher, torque than the electric motor. The electric motor can typically generate a torque of approximately 4 Nm to approximately 15 Nm, for example.

[0027] According to one embodiment, the stator of the electric motor is hollow-cylindrical. Thus, the electric motor is also annular and can be mounted on a stationary element, in particular a cylindrical or hollow-cylindrical support component.

[0028] A further aspect of the invention relates to a steering device, in particular a steer-by-wire steering device, of a vehicle. The steering device has a force feedback system, as described above and below, in particular according to the invention, a steering element, e.g., a steering wheel, a non-rotatable, i.e., rotationally fixed, steering element receiving section, and an adjustment unit. The adjustment unit has a longitudinal adjustment device for adjusting a longitudinal position of the steering element along an extension axis and / or a height adjustment device for adjusting a height position of the steering element. The steering element is arranged on the steering element receiving section so as to be rotatable about a steering element axis relative to the steering element receiving section.The force feedback system is arranged coaxially to the steering element axis on the steering element receiving section such that the stator of the brake unit and the stator of the electric motor are rotationally fixedly coupled to the steering element receiving section. The rotor of the brake unit and the rotor of the electric motor are rotationally fixedly coupled to the steering element.

[0029] The force feedback system enables a space-saving design of the steering system. This means that the installation space for the steering system with the above and following force feedback system can be reduced, particularly due to the coaxial arrangement of the force feedback system to the steering element axis. Furthermore, the weight of the steering system is reduced, which can particularly improve so-called crash characteristics, i.e., the behavior of the steering system in the event of an accident (crash). A rotational movement of the steering element, e.g., a steering movement by a vehicle driver, rotates the rotor of the brake unit and the rotor of the electric motor relative to their respective stators. By energizing the respective coils, a magnetic field can be generated, which in turn creates a specific torque. Since both rotors are rotationally fixedly coupled to the steering element, the two rotors rotate together and at the same speed.In particular, it is conceivable that the rotor of the brake unit and the rotor of the electric motor are formed separately from one another or integrally in one piece.

[0030] According to one embodiment, the steering element receiving section is designed as a hollow cylindrical support component, e.g. a fixed hollow shaft, which serves for the passage of cables, in particular for the electrical contacting of the force feedback system, in particular the brake unit and / or the electric motor, and / or for the electrical contacting of components arranged in the steering element, e.g. airbags, etc.

[0031] This means that the cables are largely protected from external influences, in particular kinking, crushing, etc. by other, particularly moving, components.

[0032] This prevents premature failure of the electrical system, particularly due to cable damage. In particular, the brake unit and the electric motor are arranged radially outside the cable feedthrough and / or electrical contacts, such as overmolded lead frames, of the brake unit, the electric motor, the airbag, etc.

[0033] According to one embodiment, the force feedback system is arranged between the steering element and the adjustment unit, viewed in the axial direction, i.e. in particular along the steering element axis and / or the extension axis.

[0034] As a result, the distance between the axial end of the adjustment unit facing the force feedback system and the force feedback system or the steering element remains unchanged, regardless of the selected length and / or height position of the steering element. This means that the distance between the axial end of the adjustment unit facing the force feedback system and the force feedback system or the steering element is always the same for every possible position of the length adjustment device and / or for every possible position of the height adjustment device. An electrical or electronic system, with which the force feedback system, in particular the brake unit and / or the electric motor, an airbag, etc. are electrically coupled, is usually provided within the length adjustment device. The distance between the electrical or electronic system also remains unchanged.The electronics in the associated components of the force feedback system and / or the steering element remain unchanged, so that the cables, etc., connecting the electrical or electronic components to the respective components do not need to be configured to compensate for or bridge multiple, varying distances. This simplifies the assembly of the steering system. In addition, cable routing can be simplified, and in particular, so-called "cable spaghetti" and the resulting cable damage and potential interactions can be avoided.

[0035] One could also say that the force feedback system arranged in this way is located close to the steering element, i.e., in front of the adjustment unit, as viewed from the steering element. In particular, the force feedback system is arranged on the steering element receiving section in such a way that the brake unit is located next to the electric motor in the axial direction and behind the electric motor, as viewed from the steering element.

[0036] According to one embodiment, the steering element axis has an axial offset relative to the extension axis of the adjustment unit. This axial offset makes it possible, in particular, to provide additional vehicle components, such as a head-up display, etc., and / or to allow variations in the design of a dashboard and / or windshield.

[0037] According to one embodiment, the steering device further comprises a sensor device and / or end stop device arranged radially outside the force feedback system on the steering shaft section. This ensures that cables, in particular cables leading to the rotatable steering element (e.g., for steering wheel heating, switches, etc. for so-called multifunction steering wheels, etc.), are arranged away from rotating components, e.g., the rotors, thus preventing the cables from tearing off.

[0038] Detailed description based on drawing

[0039] Further measures improving the invention are presented in more detail below, together with the description of preferred embodiments of the invention, with reference to the figures. It shows:

[0040] Fig. 1 is a perspective longitudinal sectional view of a brake unit according to an embodiment of the invention,

[0041] Fig. 2 is a longitudinal sectional view of a brake unit according to an embodiment of Fig. 1,

[0042] Fig. 3 is a front view of a brake unit according to an embodiment of the invention,

[0043] Fig. 4 is a perspective view of a subassembly of a brake unit according to an embodiment of the invention,

[0044] Fig. 5 is an exploded view of the subassembly of a brake unit shown in Fig. 4 according to an embodiment of the invention,

[0045] Fig. 6 is a perspective longitudinal sectional view of a partial force feedback system according to an embodiment of the invention,

[0046] Fig. 7 is an enlarged partial view of the longitudinal section from Fig. 6,

[0047] Fig. 8 is a perspective view of a partial force feedback system according to an embodiment of the invention;

[0048] Fig. 9 is an exploded view of the perspective view of Fig. 8,

[0049] Fig. 10 is a perspective view of a steering device according to an embodiment of the invention,

[0050] Fig. 11 is a perspective longitudinal sectional view of a portion of the steering device according to the embodiment of Fig. 10,

[0051] Fig. 12 is a longitudinal sectional view of a portion of the steering device according to the embodiment of Fig. 10, and

[0052] Fig. 13 is an enlarged view of section XIII from Fig. 12. The figures are merely schematic and serve only to aid understanding of the invention. The same elements are provided with the same reference numerals.

[0053] Fig. 1 to 3 show schematically and exemplarily different views of a brake unit

[0054] 1 according to an embodiment of the invention. The brake unit 1 according to the exemplary embodiment shown is a substantially ring-shaped magnetorheological brake unit 1. Magnetorheological brakes comprise a magnetorheological medium, such as a magnetorheological fluid (so-called MRF brake units) or a magnetorheological powder (so-called MRP brake units).

[0055] The exemplary brake unit 1 shown in Figs. 1 to 3 comprises a one-piece stator 2, a rotor 3, and a coil 4. The stator 2 is substantially annular and has a coil receiving portion 5 in which the coil 4 is received. The rotor 3 is annular or hollow-cylindrical and is arranged radially outside the stator 2 and the coil 4 such that a gap 6 is formed between the stator 2 and the rotor 3 in the radial direction R. The gap 6 is filled with a magnetorheological medium 7 and can therefore also be referred to as a shear gap 8. The stator

[0056] 2 is a stationary component and is designed to be attached to a stationary element via fastening features 10, in this case, for example, a receptacle for screws, bolts, rivets, etc. The rotor 3 is rotatable relative to the stator 2.

[0057] In addition, the brake unit 1 has two essentially annular or purely disc-shaped side walls 9, which are arranged in the axial direction A, i.e., in the direction of a longitudinal axis L of the brake unit 1, on both sides of the stator 2. The two side walls 9 are coupled radially outwardly to the rotor 3 in a rotationally fixed manner and, together with the rotor 3, form an enclosing device 11, which is designed to enclose the stator 2 and the coil 4. Since the side walls 9 are coupled to the rotor 3 in a rotationally fixed manner, the entire enclosing device 11 is rotatable relative to the stator 2.

[0058] Within an interior space 12 formed by the enclosure device 11, in which the stator 2 and the coil 4 are accommodated, two sealing devices 13 are further arranged, which are designed to seal the interior space 12 from the outside. This can prevent, in particular, the magnetorheological medium 7 from escaping from the interior space 12. The sealing devices 13 are arranged here, for example, on sealing seats 14, which are formed integrally with the side walls 9. Thus, according to the exemplary embodiment of the brake unit shown here, the sealing devices 13 are also rotatable relative to the stator 2. The sealing devices 13 are designed here, for example, as quad rings or X-rings. Alternatively, other embodiments for the sealing devices 13, e.g. V-rings, are also conceivable.

[0059] The coil 4 has electrical contacts 14, which are embodied here, for example, as cable tails 15 that extend radially inward within the stator 2. Furthermore, the stator 2 has a radially and axially extending passage opening 16 through which the electrical contacts 14 of the coil 4 are exposed. Thus, the electrical contacts 14 of the coil 4 can be easily coupled to an electrical system (not shown) within the passage opening 16.

[0060] The rotor 3 is made of a ferrous material, whereas the side walls 9 are made of a non-magnetic material, e.g. aluminum or plastic or thin stainless steel.

[0061] 4 and 5 show schematically and by way of example a two-part embodiment of the stator 2 for the brake unit 1. According to this embodiment, the stator 2 is formed from two ring-like elements 17 made of iron. A first ring-like element 17-1 has a recess 18 for receiving the coil 4 and a collar-like sealing seat (not visible in Figs. 4 and 5) for receiving one of the two sealing devices 13. Furthermore, the first ring-like element 17-1 has the passage opening 16 for contacting the electrical contacts 14 of the coil 4. A second ring-like element 17-2 also has a collar-like sealing seat 19 for receiving the other of the two sealing devices 13. Thus, the sealing devices 13 are arranged here in a rotationally fixed manner on the stator 2. This means that, in contrast to the embodiment shown in Figs. 1 to 3, the sealing devices 13 rotate according to the rotational direction shown in Fig.4 and 5 shown embodiment.

[0062] The coil 4 is here integrally housed in a carrier 20, e.g., cast in a plastic. The electrical contacts 14 of the coil 4 are designed here, for example, as contact pins 21. It is also conceivable to design the electrical contacts as contact blades (not shown). The contact pins 21 or the contact blades simplify the electrical contacting of the coil 4 compared to the cable tails 15. Fig. 6 shows a schematic and exemplary longitudinal section of a force feedback system 30 according to an embodiment of the invention, wherein only one rotor 31 of an externally rotating electric motor 32 (see Figs. 11 and 12) is shown. The force feedback system 30 further comprises the brake unit 1, which here comprises, for example, the two-part stator 2 shown in Figs. 4 and 5. The rotor 3 of the brake unit 1 is designed integrally in one piece with the rotor 31 of the electric motor 32.The integrally formed rotors 3, 31 can also be referred to as a combination rotor 33. The brake unit 1 shown in Fig. 6 also has two annular disk-shaped side walls 9, which, however, are designed differently from one another. Thus, a first of the two side walls 9 can be referred to as a first side cheek 34. The first side cheek 34 is fastened to the rotor 33 at an axial end of the combination rotor 33 facing away from the electric motor 32. A second of the two side walls 9 is arranged in the rotor 33 in such a way that, together with the first side cheek 34 and a partial section of the rotor 33, it forms the enclosure device 11 for receiving the stator 2 and the coil 4 (see also Fig. 7). The second of the two side walls 9 can be referred to as the second side cheek 34.

[0063] Fig. 7 shows an enlarged view of a portion of the brake unit 1 shown in Fig. 6. In Fig. 7, it can be seen that the combination rotor 33 has a shoulder 35 which serves to receive the second side cheek 34. In addition, the combination rotor 33 has a circumferential notch in the region of the shoulder 35, which notch is used during production from a tool run-out, and which also enables a magnetic separation between the rotor 3 belonging to the brake unit 1 and the rotor 31 belonging to the electric motor 32. Furthermore, it can be seen that the sealing device 13 according to this exemplary embodiment is designed as a V-seal 36. This type of sealing device 13 has sealing lips which slide against the respective side cheeks 34 in order to seal the interior 12 from the outside.In the area of ​​the rotor section 31 of the combination rotor 33 associated with the electric motor 32, the rotor 33 further has magnet slots 37 on its outer circumference, which serve to accommodate magnets 38 (see, for example, Fig. 8). Such magnets 38 facing away from a shear gap (not shown) of the electric motor 31 are more robust because they cannot jam in the shear gap, and are more homogeneous because their dispersion in field strength and orientation is smoothed by the iron of the rotor 33.

[0064] 8 and 9 show schematically and by way of example a force feedback system 30 according to an embodiment of the invention, which largely corresponds to the embodiment shown in Fig. 6, wherein in Figs. 8 and 9 only the rotor 31 or 33 of the electric motor 32 is shown. The exemplary embodiment of the force feedback system 30 shown in Figs. 8 and 9 differs from the exemplary embodiment shown in Fig. 6 only in the design of the combination rotor 33 in the region of the combination rotor 33 that represents the rotor 31. This region is referred to below as the rotor region 31 for the sake of clarity. Here it can be seen that the rotor region 31 has a spur gear 39 at its “free” axial end. The spur gear serves to improve torque support between the combination rotor 33 and a housing (not shown) that rotates with the rotor 33.

[0065] Fig. 9 shows that the second side wall 34 further has filler openings 40 arranged along the circumference on the end face of the side wall 34 facing away from the stator 2. The filler openings 40 serve to fill the magnetorheological medium 7 into the interior space 12, in particular into the shear gap 8, when the brake unit 1 is assembled. After the medium has been filled into the interior space 12, the filler openings are sealed to prevent the medium 7 from escaping, particularly during operation.

[0066] Fig. 10 shows a schematic and exemplary perspective view of a steering device 50 according to an embodiment of the invention. The steering device 50 is designed as a steer-by-wire steering device and has a steering element designed as a steering wheel 51, which is arranged on a non-rotating steering element receiving section 52, wherein the steering wheel 51 is rotatable relative to the steering element receiving section 52 about a steering wheel axis LR. Furthermore, the steering device 50 has the force feedback system 30 and an adjustment unit 53. The adjustment unit 53 has a longitudinal adjustment device 54 for longitudinally adjusting a position of the steering wheel 51 along a longitudinal adjustment axis LV and a height adjustment device 55 for height adjustment of a position of the steering wheel 51. The longitudinal adjustment device 54 here comprises a longitudinal adjustment actuator 56, which is shown in Fig.10 is only partially visible, as well as a length-adjustable extension 57 which can be moved along the longitudinal adjustment axis LV by actuating the longitudinal adjustment actuator 56. The adjustment unit 53 can also be fastened to a vehicle body via brackets 58. In particular, an electronic system (not visible in Fig. 10), e.g. an electronic control unit, for controlling the electrical and electronic components, such as the force feedback system 30, airbags (not shown) provided on the steering wheel 51, etc., is arranged within the length-adjustable extension 57. An axial end of the steering element receiving section 52 is coupled to an axial end of the length-adjustable extension 57 in such a way that a displacement of the extension 57 along the longitudinal adjustment axis LV causes a displacement of the steering receiving section 52.Furthermore, the steering receiving section 52 is arranged on the extension 57 such that the longitudinal adjustment axis LV and the steering wheel axis LR are offset from one another. It is also conceivable for the steering wheel axis LR to be arranged at an angle, so to speak, bent, to the longitudinal adjustment axis LV.

[0067] The force feedback system 30 is also arranged on the steering element receiving section 52. More precisely, the force feedback system 30 is arranged between the steering wheel 51 and the adjustment unit 53, viewed in the axial direction. Thus, the force feedback system 30 in Fig. 10 is a so-called near-steering-wheel force feedback system. Furthermore, a sensor device 59 and / or an end stop device 60 is arranged on the steering element receiving section 52 and radially outside the force feedback system 30. The steering element receiving section 52 and the components arranged thereon, i.e., the steering wheel 51, the force feedback system 30, and the devices 59 and 60, are described in more detail below with reference to Figs. 11 to 13.

[0068] 11 to 13 show schematically and by way of example a portion of the steering device 50 comprising the steering element receiving region 51 in various representations. The steering wheel 51 or a housing 62 rotating with the steering wheel 51 is arranged rotatably relative to the steering element receiving section 52 via a bearing 61. The force feedback system 30 is arranged adjacent to the steering wheel 51 in the axial direction A on the steering element receiving section 52 in such a way that a stator 41 of the electric motor 32, which is designed as an external rotor, and the stator 2 of the brake unit 1 are arranged rotationally and axially fixed on the steering element receiving section 52. Thus, the force feedback system 30, in particular the brake unit 1 and the electric motor 32, are arranged coaxially to the steering wheel 51.

[0069] The rotor 3 of the brake unit 1 and the rotor 31 of the electric motor 32 are arranged in a rotationally and axially fixed manner in the rotatable housing 62, which in turn is rotationally fixedly coupled to the steering wheel 51. Thus, the rotors 3, 31 rotate (via the housing 62) together with the steering wheel 51. The steering element receiving section 52 is furthermore designed as a hollow cylinder, with an internal cavity 63 thus formed serving as a feedthrough and / or receptacle for cables or electrical contacts, e.g., overmolded lead frames, etc., via which the force feedback system 30, in particular the coil 4 of the brake unit 1 and the coil (not shown) of the electric motor 32, as well as airbag systems in the steering wheel 51, are coupled to the electronics arranged in the extension 57. As a result, the cables, etc., are removed and protected from rotating components, such as the rotors 3, 31.The sensor device 59 and the end stop device 60, which here, for example, is designed to be multi-turnable with a slide 64 guided in a screw groove, are arranged radially outside the force feedback system 30, whereby the electrical contact, i.e. the coupling of these devices 59, 60 to the electronics, can be carried out separately and away from the force feedback system 30, in particular away from the rotating rotors 3, 31. Figs. 12 and 13 serve in particular to explain which components or elements in the partial area of ​​the steering element receiving section 52 are rotatable (dotted pattern), which elements are stationary (line pattern), which elements are axially displaceable (diamond pattern), and which elements carry current (grid pattern).

[0070] List of reference symbols

[0071] 1 brake unit

[0072] 2 Stator

[0073] 3 Rotor

[0074] 4 coil

[0075] 5 Coil receiving section

[0076] 6 gap

[0077] 7 magnetorheological medium

[0078] 8 Shear gap

[0079] 9 Side wall

[0080] 10 Fastening feature

[0081] 11 Enveloping device

[0082] 12 Interior

[0083] 13 Sealing device

[0084] 14 electrical contact

[0085] 15 cable tail

[0086] 16 passage opening

[0087] 17, 17-1, 17-2 ring-like element

[0088] 18 Deepening

[0089] 19 Seal seat

[0090] 20 carriers

[0091] 21 contact pin

[0092] 30 Force Feedback System

[0093] 31 Rotor

[0094] 32 electric motor

[0095] 33 Combi-Rotor

[0096] 34 side panel

[0097] 35 paragraph

[0098] 36 Shaft seal

[0099] 37 magnetic slot

[0100] 38 Magnet

[0101] 39 spur gearing

[0102] 40 Filling opening

[0103] 41 Stator 50 Steering device

[0104] 51 Steering wheel

[0105] 52 Steering element receiving section

[0106] 53 Adjustment unit

[0107] 54 Longitudinal adjustment device

[0108] 55 Height adjustment device

[0109] 56 Longitudinal adjustment actuator

[0110] 57 length-adjustable extension

[0111] 58 bracket

[0112] 59 Sensor device

[0113] 60 End stop device

[0114] 61 Storage

[0115] 62 housings

[0116] 63 Cavity

[0117] 64 sliders

[0118] A axial direction

[0119] R radial direction

[0120] L Longitudinal axis

[0121] LR steering wheel axle

[0122] LV longitudinal adjustment axis

Claims

Claims 1 . Brake unit (1) for a force feedback system (30) for a steering device (50), in particular a steer-by-wire steering device, of a vehicle, comprising: a stator (2) which is annular and has a coil receiving section (5), a coil (4) which is arranged in the coil receiving section (5) of the stator (2), a rotor (3) which is hollow-cylindrical and is arranged radially outside the stator (2) and the coil (4) such that a gap (6) is formed between the stator (2) and the rotor (3), wherein the rotor (3) is rotatable relative to the stator (2), an enclosing device (11) which is designed to enclose the stator (2) and the coil (4), wherein the enclosing device (11) is formed by annular side walls (9) which are arranged in the axial direction (A) on both sides of the stator (2), and the rotor (3), which is non-rotatably coupled to the side walls (9),at least two sealing devices (13) which are designed to seal an interior space (12) formed by the enclosing device (11) from the outside, and wherein the stator (2) has a radially and / or axially extending passage opening (16) which is designed to expose electrical contacts (14) of the coil (4).

2. Brake unit (1) according to claim 1, wherein the stator (2) is formed in one part or in several parts.

3. Brake unit (1) according to claim 1 or 2, wherein the gap (6) between the stator (2) and the rotor (3) is formed as a cylindrical shear gap (8) which is adapted to receive a medium (7).

4. Brake unit (1) according to claim 3, wherein the medium (7) has magnetorheological properties.

5. Brake unit (1) according to one of claims 1 to 4, wherein the electrical contacts (14) of the coil (4) are designed as pins (21) and / or as cable contact terminals (15, 21).

6. Brake unit (1) according to one of claims 1 to 5, wherein the coil (4) is accommodated in an annular carrier (20).

7. Brake unit (1) according to one of claims 1 to 6, wherein the sealing devices (13) are each arranged on a sealing seat which extends in the axial direction (A), wherein the sealing seats are formed integrally in one piece with the side walls (9), or wherein the sealing seats (19) are formed integrally in one piece with the stator (2).

8. Brake unit (1) according to one of claims 1 to 7, wherein the stator (2) is designed to be coupled to a stationary element (52) in a form-fitting and / or force-fitting and / or material-fitting manner.

9. Force feedback system (30) for a steering device (50), in particular a steer-by-wire steering device, of a vehicle, comprising: a brake unit (1) according to one of the preceding claims, and an electric motor (32), wherein the electric motor (32) has a stationary stator (41) and a rotor (31) which is rotatable relative to the stator (41) and is arranged radially outside the stator (41), wherein the brake unit (1) and the electric motor (32) are arranged coaxially and adjacent to one another in the axial direction (A).

10. Force feedback system (30) according to claim 9, wherein the stator (41) of the electric motor (32) is hollow-cylindrical.

11. Steering device (50), in particular a steer-by-wire steering device, of a vehicle, comprising: a steering element (51), a non-rotatable steering element receiving section (52), a force feedback system (30) according to claim 9 or 10, and an adjusting unit (53) comprising a longitudinal adjusting device (54) for adjusting a longitudinal position of the steering element (51) along an extension axis (LV) and / or a height adjusting device (55) for adjusting a height position of the steering element (51), wherein the steering element (51) is arranged on the steering element receiving section (52) so as to be rotatable about a steering element axis (LR) relative to the steering element receiving section (52), wherein the force feedback system (30) is arranged on the steering element receiving section (52) coaxially to the steering element axis (LR) in such a way that the stator (2) of the Brake unit (1) and the stator (41) of the electric motor (32) are rotationally coupled to the steering element receiving section (52), and wherein the rotor (3) of the brake unit (1) and the rotor (31) of the electric motor (32) are rotationally coupled to the steering element (51).

12. Steering device (50) according to claim 11, wherein the steering element receiving section (52) is designed as a hollow cylindrical support component which serves to pass through cables.

13. Steering device (50) according to claim 11 or 12, wherein the force feedback system (30) is arranged between the steering element (51) and the adjusting unit, viewed in the axial direction (A). (53) is arranged.

14. Steering device (50) according to one of claims 11 to 13, wherein the steering element axis (LR) has an axial offset relative to the extension axis (LV) of the adjusting unit (53).

15. Steering device (50) according to one of claims 11 to 14, further comprising a sensor device (59) and / or end stop device (60) which is / are arranged radially outside the force feedback system (30) on the steering element receiving section (52).

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