WHEEL MODULE WITH A BRAKE UNIT AND VEHICLE WITH THE WHEEL MODULE

Description

[0001] The invention relates to a wheel module with a brake unit and a vehicle with the wheel module.

[0002] For human-powered vehicles, such as bicycles, drum brakes, disc brakes, or shoe brakes are commonly used. Each braking system has different advantages in terms of braking efficiency, system cost, ease of maintenance, etc.

[0003] For example, DE 200 16 878 U1 describes a scooter with a braking device configured as a hydraulically activated disc brake. The braking device comprises a brake disc connected to a wheel in a rotationally fixed manner and a brake caliper rigidly connected to the frame of the scooter, the brake caliper containing brake pads acting on the brake disc. A wheel module according to the preamble of claim 1 is disclosed in US 2002 / 0043777 A1. Further prior art is described in EP 0 291 430 A1 and US 2 581 941 A.

[0004] The object of the present invention is to propose a wheel module with a brake unit having a modified structure for a vehicle. This object is achieved by a wheel module having the features of claim 1 and by a vehicle having the features of claim 6. Preferred or advantageous embodiments of the invention emerge from the subclaims, the following description, and the accompanying figures.

[0005] The subject of the invention is a braking unit that is suitable and / or designed for a vehicle. In particular, the vehicle is designed as a single- or multi-track vehicle. Preferably, the vehicle is designed as an electrically powered vehicle. For example, the vehicle is a small electric vehicle, where "small electric vehicle" refers to vehicles without a seat or self-balancing vehicles with or without a seat.

[0006] The vehicle is preferably designed as a small or micro vehicle or as an electric vehicle. The vehicle preferably has at least one wheel. With only one wheel, the vehicle can be designed as an electric unicycle, e.g. as a so-called monowheel or solowheel. With two or more wheels, the vehicle is preferably designed as a scooter, in particular as an electric motorcycle, as an electric motor scooter, as an electric scooter, electric kick scooter, electric scooter, e.g. e-scooter, as a Segway, hoverboard, kickboard, skateboard, longboard or similar. Alternatively, the vehicle can be designed as a bicycle, in particular as an electric bicycle, e.g. as a pedelec or as an e-bike. Alternatively, the vehicle can be designed as a multi-track bicycle, in particular with three or more wheels. For example, the vehicle can be a transport or cargo bike, in particular a motorized orelectrically powered transport or cargo bike, in particular a three-wheeled or four-wheeled pedelec or a rickshaw, in particular with or without a roof, or a cabin scooter.

[0007] The vehicle may comprise one or more of the brake units. The brake unit has a housing, wherein the housing is arranged and / or can be arranged on the vehicle in a stationary and / or rotationally fixed manner. Preferably, the housing is arranged coaxially with a stationary or rotating wheel axle of the vehicle. In particular, the wheel axle penetrates the housing. For this purpose, the housing has, for example, a through-opening for accommodating the wheel axle.

[0008] The brake unit comprises a brake body device, wherein the brake body device supports a stationary brake partner for a braking device for the vehicle. In particular, the brake body device forms the stationary brake partner in the housing, wherein a rotating brake partner is connected in a rotationally fixed manner to a wheel of the vehicle.

[0009] The brake unit has a main axis, whereby the main axis is understood to be a structural and / or imaginary auxiliary axis. The main axis can be defined, for example, by the housing, in particular by the through-hole or the wheel axle. Alternatively or additionally, the main axis can be defined by the brake body device.

[0010] The brake unit has an actuator device for moving, in particular actuating, the brake body device. In particular, the braking force is transmitted from the brake body device, in particular from the stationary brake partner, to the rotating brake partner. In the most general embodiment of the invention, the actuator device can be hydraulically actuated.

[0011] Within the scope of the invention, it is proposed that the stationary braking partner be designed as a brake disc. In particular, the brake disc rotates completely and / or 360° around the main axis. The brake disc can be geometrically implemented as a disc or annular disc; alternatively, it can be designed as a section of a larger component, thus forming a brake disc section within this component.

[0012] One consideration of the invention is that the use of a stationary brake disc allows the overall structure of the braking device to be redesigned and the properties of the braking device to change. For example, it is possible to position the brake disc further outwards axially and still arrange the actuator device on the stationary part of the braking device, so that the number and / or weight of the rotating parts is kept small. By arranging the braking unit and thus the brake disc on an axial outer side of the bicycle wheel, the temperature management of the braking device is also changed, since the brake disc is known to heat up during heavy braking. Because the brake disc is positioned axially on the outside, the heat can be dissipated more effectively and the brake disc can therefore be cooled more effectively.

[0013] In a preferred embodiment of the invention, the brake disc is made of metal or ceramic. In particular, the stationary brake partner is designed as the hard brake partner, whereas the rotating brake partner is implemented as the soft brake partner. Due to the high thermal conductivity, particularly of the metal, the heat generated during heavy braking is evenly distributed and / or dissipated on or within the brake disc.

[0014] The brake disc provides a braking surface, wherein the braking surface is preferably designed as an annular surface, in particular a circular ring surface, for introducing the braking force. In particular, the braking surface is formed by a material surface of the brake body device. For example, the braking surface can be formed by a treated surface of the brake disc, e.g., by grinding and / or honing the surface, for example, to reduce the roughness of the braking surface.

[0015] The braking surface is preferably formed on the brake disc in a radial direction with respect to the wheel axis and / or extends in a radial plane to the main axis. The braking surface is preferably formed exclusively on one side of the brake disc. In particular, the braking surface is arranged on an axially inner side of the brake unit. Alternatively or additionally, the braking surface is formed circumferentially, in particular uninterrupted or largely uninterrupted, to the main axis. As is usual with brake discs, in all alternatives the braking surface can be perforated by ventilation holes, fastening holes or the like. The mentioned alternatives reflect the fact that the brake disc is not limited to one segment with regard to the braking surface, but extends over 360° around the main axis.This means that the area for introducing braking energy is comparatively large, so that the heat resulting from braking remains comparatively low.

[0016] In a preferred embodiment of the invention, the actuator device moves the brake body device relative to the housing in the axial direction toward the main axis. Thus, the brake disc is advanced in the axial direction to generate the braking force.

[0017] In a preferred structural embodiment of the invention, the actuator device is designed as a hydraulic device. The hydraulic device is thus designed for the hydraulic activation of the braking device. For example, the hydraulic device can be actuated by a brake lever of the vehicle and activate the braking device so that a rotating wheel can be braked. For example, a cylinder of the hydraulic device can be operatively connected to the housing, and a piston of the hydraulic device can be operatively connected to the brake body device. Particularly preferably, the cylinder is fixedly or positively connected to the housing, and the piston is connected to the brake body device. Particularly preferably, the hydraulic device can have an annular space and an annular piston, wherein the annular piston is arranged in the annular space. A hydraulic fluid for actuating the annular piston is arranged in the annular space.The annular space and the annular piston are designed to run around the main axis.

[0018] The brake unit has a guide device that guides the brake body device in the radial direction, particularly toward the main axis, during axial movement of the brake body device relative to the housing. This prevents, for example, tilting between the brake body device and the housing.

[0019] The guide device is provided with a master guide and an auxiliary guide. Thus, the guide device has at least or exactly two guides. The master guide and the auxiliary guide are arranged off-center relative to the main axis. In particular, they are not positioned coaxially, but offset relative to the main axis.

[0020] One consideration of the further development is that when the braking force is transferred from the stationary braking partner to the rotating braking partner, in addition to axial forces, in particular braking forces or corresponding counterforces, torques about the main axis are introduced into the brake body device. To prevent tilting or twisting of the brake body device relative to the housing, it is proposed to equip the guide device with at least two separate individual guides.

[0021] In a preferred design embodiment of the invention, the master guide has a first radial clearance and the auxiliary guide has a second radial clearance. The radial clearance can be measured locally in the master guide and in the auxiliary guide. If the master guide and / or the auxiliary guide are rotationally symmetrical, the radial clearance can be measured locally in any direction relative to the master guide or the auxiliary guide. Alternatively or additionally, the radial clearance can be measured in the direction of rotation around the main axis. Thus, the torque in the direction of rotation is absorbed primarily by the master guide and secondarily by the auxiliary guide. This means that the torque can be safely dissipated.On the other hand, the different radial play ensures that there is no overdefinition of the brake unit in the direction of rotation around the main axis and thus jamming of the brake body device is avoided even at different temperatures, etc.

[0022] In a preferred structural embodiment, the master guide has a first axial section which is arranged on the brake body device and in particular forms a component of the brake body device. Furthermore, the master guide has a first guide section which is arranged on the housing and in particular forms a component of the housing. The first axial section is arranged coaxially in the first guide section and is guided thereby. Alternatively or additionally, the auxiliary guide has a second axial section which is arranged on the brake body device and in particular forms a component of the brake body device. Furthermore, the auxiliary guide has a second guide section which is arranged on the housing and in particular forms a component of the housing. The second axial section is arranged coaxially in the second guide section and is guided thereby.The second radial clearance is measured between the second axle section and the second guide section, preferably in the circumferential direction around the main axis or, alternatively, around a separate central axis. Preferably, the axle sections and / or the guide sections are rotationally symmetrical in the guide area.

[0023] It can be provided that the axle sections each have a guide surface, thus a first and a second guide surface, for contact with the guide sections. This configuration has the advantage that very few components or parts are used. On the other hand, the axle sections or the guide sections must be made of a corresponding, functionally suitable material. Alternatively, it is particularly preferred that a first guide sleeve, which provides the first guide surface, is placed on the first axle section. Alternatively or additionally, the second axle section has a second guide sleeve, which provides the second guide surface. In particular, the first and / or the second guide sleeve is designed as a straight hollow cylinder.By using a guide sleeve, a hard and thus low-wear guide surface can be provided, although the axle sections of the brake body device can be made of any material.

[0024] The first radial clearance is measured between the first guide surface, in particular the first axle section or (if present) the first guide sleeve, and the first guide section, preferably in the circumferential direction around the main axis or alternatively around its own central axis. The second radial clearance is measured between the second guide surface, in particular the second axle section or (if present) the second guide sleeve, and the second guide section, preferably in the circumferential direction around the main axis or alternatively around its own central axis.

[0025] In a preferred development of the invention, the housing has a housing base body. The housing base body can be manufactured, for example, by die-cast aluminum. It is particularly preferably provided that the first and / or the second guide section is formed integrally by the housing base body. The guide sections are thus formed by a section of the die-cast aluminum and can therefore be manufactured cost-effectively. Alternatively or additionally, the brake body device has a brake base body. The brake base body can be manufactured, for example, by die-cast aluminum. It is particularly preferably provided that the first and / or the second axle section is formed integrally by the brake base body. The axle sections are thus formed by a section of the die-cast aluminum and can therefore be manufactured cost-effectively.

[0026] In one possible design configuration, the brake body device comprises a force distribution plate. The force distribution plate is particularly embodied as a sheet metal plate. The force distribution plate is operatively connected to the hydraulic device. Particularly preferably, the force distribution plate comprises a contact surface for the annular piston or for an adapter piece that rests against the annular piston. The force distribution plate is connected to the brake body device via the first, the second, and also via at least or exactly one third axle section. Preferably, the force distribution plate is connected to the brake body via the at least or exactly three axle sections.

[0027] In a preferred design, the three axle sections can be evenly distributed in the circumferential direction in order to introduce the braking force into the brake body device as evenly as possible. The third axle section is guided in the radial direction and / or in the circumferential direction with an even greater radial clearance than the first and / or second radial clearance, or is not guided at all.

[0028] In a preferred embodiment of the invention, the brake unit has a reset device for resetting the brake body device. The reset device has a first return spring, a second return spring, and a third return spring. The first return spring is assigned to the master guide, the second return spring to the auxiliary guide, and the third return spring is assigned to the third axle section. In this way, the reset force is also introduced evenly after the braking process. On one side, the return springs and / or the reset device are supported on the housing and, on the other side, preferably on the brake base body.

[0029] Another subject matter of the invention relates to a wheel module for a vehicle, wherein the wheel module has a brake unit as described above. The vehicle can comprise one or more of the wheel modules. The wheel module has a wheel. In particular, the wheel is a front or rear wheel of the vehicle. The wheel comprises a wheel rim and preferably a tire, wherein the tire is arranged on the wheel rim. The tire is particularly preferably an air-filled and / or fillable rubber tire.

[0030] It is provided that the wheel module has a rotating braking partner of the braking device, wherein the rotating braking partner is connected to the wheel and / or the wheel rim in a rotationally fixed manner. Particularly preferably, the rotating braking partner is designed as a brake pad or comprises one. In particular, upon actuation of the braking device, the brake pad and the brake disc are moved relative to one another in the axial direction and brought into frictional and / or force-locking contact with one another, such that a braking torque is transmitted to the wheel. Preferably, the brake disc forms a metallic partner and the brake pad a friction partner. In particular, the brake disc and the brake pad are matched to one another in such a way that the brake pad is subject to greater wear.

[0031] In particular, the brake pad is arranged on an axial end face of the wheel rim. Preferably, the brake pad is applied to the wheel rim directly or indirectly. In particular, the brake pad covers at least a portion of an outer side of the wheel rim. In principle, the brake pad can be arranged on the wheel rim in a discontinuous manner or in several portions. However, the brake pad is particularly preferably designed to be continuous all the way around.

[0032] One advantage of this refinement is that, by arranging the brake pad on the rim, the braking device can be positioned on the wheel in a particularly space-saving manner. Furthermore, by arranging the brake pad on the wheel rim, the braking device can be easily adapted to the size of the wheel, in particular to the size of the wheel rim. In particular, unlike conventional disc brake brake shoes, the braking device protrudes only slightly outward, significantly reducing the risk of protruding components that can also heat up.

[0033] In a preferred embodiment of the invention, the brake pad remains axially stationary on the wheel rim. In particular, the brake disc is arranged so as to be rotationally fixed in the circumferential direction and displaceable in the axial direction relative to the wheel axis. Particularly preferably, the brake pad rotates about the axis of rotation when the vehicle is in motion, with the brake disc remaining stationary in the circumferential direction. When the braking device is actuated, the brake disc is subjected to a braking force to generate the braking torque and is thus pressed against the brake pad in an axial direction.

[0034] One of the considerations of the further development is that, due to the axial displacement of the brake disc, only the brake pad is required on the wheel side. This proposes a compact braking device with fewer components. Furthermore, it enables easy connection to the wheel rim, especially for small tire diameters.

[0035] In a further preferred embodiment of the invention, the brake pad is annular and arranged coaxially and / or concentrically with the wheel rim with respect to the wheel axle. In particular, the brake pad defines an annular surface surrounding the axis of rotation, which is arranged coaxially and / or concentrically with the brake disc and / or the wheel rim and / or the wheel axle. Particularly preferably, the brake disc makes flat contact with the annular surface when the braking device is actuated. One idea of ​​the further development is to propose a braking device which is characterized by improved braking performance. The annular design of the brake pad increases the contact surface in contact with the brake disc.

[0036] In a further preferred implementation, the brake pad forms a thermal insulator, so that thermal insulation in the direction of the wheel rim is implemented by the brake pad. In particular, the brake pad reduces heat transfer from the braking device, particularly during a braking operation, to the wheel. The brake pad is preferably formed from a thermally insulating material. Particularly preferably, the material of the brake pad has a thermal conductivity coefficient that is significantly lower than a thermal conductivity coefficient of the material of the wheel rim. For example, the material of the brake pad has a thermal conductivity coefficient of less than 10 W / (m*K), preferably less than 1 W / (m*K), in particular less than 0.5 W / (m*K).

[0037] The advantage of the brake pad is that it significantly reduces heat transfer from the brake pad to the rim, particularly when the rotating wheel is decelerating. In particular, this prevents damage to the wheel rim and / or components integrated into the wheel, such as bearings, wheel drive, etc.

[0038] It is particularly preferred that the brake pad comprises a friction agent from the "organic" category. In particular, the friction agent is made of an organic material. The friction agent particularly preferably comprises fibers made of glass and / or rubber and / or carbon and / or aramid, in particular para-aramid, which are embedded in a resin matrix. The resin matrix is ​​preferably formed from a temperature-resistant synthetic or natural resin.

[0039] A brake pad is therefore proposed which is characterized by a high coefficient of friction and at the same time by a low thermal conductivity or heat transfer coefficient.

[0040] In a first specific embodiment, the brake pad is applied directly to the wheel rim. In particular, the brake pad is integrated into the wheel rim or applied to the wheel rim, preferably as a coating. Alternatively, or optionally additionally, the brake pad is integrally bonded to the wheel rim. In particular, the brake pad can be glued to the rim. For example, an adhesive can be used for this purpose which also has thermally insulating properties and / or is mixed with a thermally insulating additive. Thus, one consideration in the further development is to propose a brake pad characterized by a particularly narrow axial width.

[0041] In an alternative embodiment, the braking device comprises an annular brake pad carrier which, in particular, carries the brake pad. The brake pad is fastened and / or can be fastened to the wheel rim via the brake pad carrier, preferably in a force-fitting and / or form-fitting and / or material-fitting manner. Particularly preferably, the brake pad carrier is detachably fastened to the wheel rim, in particular via a screw connection. In particular, the brake pad carrier is fastened to the wheel rim via one or more fastening means, such as screws, rivets, or the like. For example, the brake pad carrier can be made of a material which also has thermally insulating properties and is simultaneously heat-resistant. Particularly preferably, the brake pad carrier is arranged coaxially and / or concentrically to the wheel rim and / or the wheel axle.One possible development option is to propose a brake pad that can be easily mounted and removed from the wheel rim. Furthermore, the appropriate choice of brake pad carrier can further enhance thermal insulation from the wheel rim.

[0042] In a further preferred embodiment, the wheel module comprises a drive device, in particular an electrically operated drive device, in particular an electric motor, which is designed and / or suitable for driving the wheel. In particular, the drive device is an electric machine. The drive device is arranged radially inside the wheel rim or integrated therein. The drive device comprises a stator which is connected in a rotationally fixed manner to the wheel axle and a rotor which is connected in a rotationally fixed manner to the wheel rim. During driving operation, a drive torque is generated by the drive device which acts on the rotor and thus the wheel, such that the wheel is driven about the axis of rotation. In particular, the brake pad designed as a thermal insulator protects the drive device from overheating, whereby the operational reliability and service life of the drive device can be significantly increased.

[0043] Preferably, the rotating braking partner and the drive device are arranged adjacent to each other, in particular directly adjacent to each other. In particular, they have an axial distance or gap of less than 3 cm, in particular less than 2 cm, and especially less than 1 cm. This allows the wheel module to be constructed particularly compactly.

[0044] The brake body device or a base body of the brake body device, which carries the stationary brake partner, is preferably made of a solid material, e.g. metal, in particular aluminum. The brake body device or base body preferably has a cooling structure on one side of a radially formed circular surface. The cooling structure is preferably designed as one or more cooling fins for exchanging thermal energy of the brake body device with an environment, e.g. ambient air. The cooling fins are preferably incorporated into the solid material of the brake body device. For example, the cooling fins are incorporated by milling into one radial circular surface of the brake body device or during primary forming. The stationary brake partner and the base body are preferably in thermal contact. In particular, they lie flat against one another in a radial plane in a thermal contact surface.Preferably, the thermal contact surface is also an annular surface. More preferably, the thermal contact surface comprises no less than 50% of the braking surface, the same area as the braking surface, or a larger area.

[0045] Thus, the brake pad prevents thermal transfer toward the drive unit. The brake disc, on the other hand, promotes thermal transfer into the base body of the brake assembly, allowing the heat to be dissipated through the cooling structure.

[0046] The wheel module preferably forms an interior space, with the two braking partners being arranged in the interior space. In particular, the interior space is delimited on one axial side by the housing and / or the braking element device and on the other axial side by the stationary braking element and / or the wheel rim and / or the drive device. On the radially outer side, it is preferred that the interior space is delimited by the wheel rim. In particular, only an annular gap remains between the braking element device and the wheel rim, with the annular gap extending in the axial direction so that the braking element device can be moved relative to the wheel rim. The wheel module is therefore particularly preferably designed as an encapsulated wheel module, with the encapsulation being implemented by an interaction between the braking element device and the wheel rim.

[0047] A further subject matter of the invention relates to a vehicle with the wheel module as described above. It is particularly preferred that the vehicle be an electric scooter or an electric scooter. In particular, the vehicle has precisely one wheel module, wherein the wheel module serves optionally for a front or rear wheel of the vehicle. Preferably, the wheel module is secured to the wheel fork or the frame via the wheel axle. In particular, the wheel fork can be connected to a handlebar of the vehicle, so that the wheel module, and thus the vehicle, can be steered.

[0048] Further features, advantages, and effects of the invention will become apparent from the following description of preferred embodiments of the invention. These show: Figure 1 a three-dimensional representation of a vehicle with a brake unit as an embodiment of the invention; Figure 2a schematic sectional view of the brake unit from the Figure 1 as a further embodiment of the invention. Figure 3 a three-dimensional, schematic axial representation of the brake unit from the Figure 1 ; Figure 4 a schematic sectional view of the wheel module from the Figure 1 as a further embodiment of the invention; Figure 5 a three-dimensional plan view of the brake unit of the previous figures.

[0049] Corresponding or identical parts are provided with the same reference numerals in the figures.

[0050] Figure 1shows a three-dimensional representation of a vehicle 1, wherein the vehicle 1 is designed as an electric scooter, electric kick scooter, or electric scooter, also known as an e-scooter. The vehicle 1 has a wheel module 2 with a wheel 3, which forms a front wheel of the vehicle 1. The wheel module 2 serves in particular to electrically drive the vehicle 1. In addition, the vehicle 1 has a rear wheel 4, in particular a non-driven one, which is rotatably mounted on a vehicle frame 5 of the vehicle 1.

[0051] The vehicle 1 has a wheel fork 6, with the wheel module 2 rotatably mounted in the wheel fork 6. The wheel fork 6 is pivotally connected to the frame 5 via a link 7, so that the wheel module 2 can be pivoted via the link 7 to steer the vehicle 1.

[0052] The wheel 3 of the wheel module 2 has a wheel rim 8 and a tire 9, with the tire 9 being arranged on the wheel rim 8. For example, the wheel rim 8 is designed as a steel, aluminum, or plastic rim. For example, the tire 9 is designed as an air-filled rubber tire.

[0053] The wheel module 3 has a wheel axle 10, which defines a main axis H with its longitudinal axis. The wheel 3 is arranged with its rotational axis coaxial with the wheel axle 10. The wheel axle 10 is fixed to the wheel fork 6, with the wheel rim 8 being rotatably mounted on the wheel axle 10 via two bearing devices, e.g., roller bearings.

[0054] To drive the wheel 3, the wheel module 2 has a drive device 11, e.g., an electric motor, integrated into the wheel rim 8. The drive device 11 has a stator that is non-rotatably connected to the wheel axle 10 and arranged between the two bearing devices in the axial direction with respect to the main axis H. Furthermore, the drive device 12 has a rotor that is non-rotatably connected to the wheel rim 8. When the vehicle 1 is in operation, the wheel rim 8 is driven by the drive device 11, with the wheel 3 rotating about the main axis H.

[0055] The wheel module 2 has a braking device 12, which serves to transmit a braking torque to the wheel 3. The braking device 12 is designed as a friction brake and is arranged on one side of the wheel rim 8 and / or operatively connected to the wheel rim 8.

[0056] The braking device 12 has an annular brake pad, in particular one which encircles the main axis H, as a rotating braking partner and a brake disc 13 ( Figure 2 ) as a stationary braking partner, wherein the brake pad and the brake disc 13 are arranged coaxially to one another with respect to the main axis H. The brake pad is mounted on an axial end face of the wheel rim 8 in a rotationally fixed manner with respect to the main axis H, so that the brake pad is carried by the wheel rim 8 during driving and rotates about the main axis H. The brake disc 13 is movable in an axial direction AR towards the brake pad and in an axial opposite direction GR away from the brake pad. In the direction of rotation about the main axis H, the brake disc 13 is coupled in a rotationally fixed manner to the wheel axle 10 or the wheel fork 6.

[0057] In an actuated state of the braking device 12, the brake disc 13 contacts the brake pad, so that a frictional connection is formed in order to brake the rotating wheel 3 by friction between the brake disc 13 and the brake pad.

[0058] The Figure 2 shows a schematic longitudinal section through a brake unit 14, wherein the brake unit 14 forms the fork-fixed part of the brake device 12, in particular the brake unit 14 carries the brake disc 13 and displaces it in the axial direction AR and the opposite direction GR.

[0059] The brake unit 14 has a housing 15, wherein the housing 15 is arranged coaxially to the main axis H and is non-rotatably mounted on the wheel fork 6. The brake unit 14 has a hydraulic device 16, wherein the hydraulic device 16 is arranged, in particular integrated, in the housing 15.

[0060] The hydraulic device 16 has a connection 17 via which it can be subjected to hydraulic pressure. The connection 17 is fluidly connected to an annular space 18 as a pressure chamber, wherein the annular space 18 forms a cylinder of the hydraulic device 16. The annular space 18 is arranged coaxially to the main axis H. An annular piston 19 is arranged in the annular space 18, wherein the annular piston 19 can be hydraulically displaced in the axial direction AR in the annular space 18 as a cylinder. The annular piston 19 is formed in two parts in the axial direction. The housing 15 has a receiving section 20 for receiving the wheel axle 10, wherein the receiving section 20 forms an inner wall of the annular space 18. Furthermore, the housing 15 has an outer wall 21, wherein the outer wall 21 delimits the annular space 18 radially on the outside. The receiving section 20 and the outer wall 21 are designed as a one-piece housing base body 22.

[0061] The brake unit 14 has a brake body device 23, wherein the brake body device 23 supports the brake disc 13 and is displaced together with the latter in the axial direction AR and in the opposite axial direction GR by the hydraulic device 16. The brake body device 23 has a force distribution plate 24, which for stability reasons is designed as a pot with a collar. In a radial inner region, the force distribution plate 24 rests on the annular piston 19, so that the force distribution plate 24 is carried along during an axial movement of the annular piston 19. The brake body device 23 has a brake base body 25, wherein the brake base body 25 supports the brake disc 13.The brake base body 25 is connected to the force distribution plate 24 via a first, a second and a third screw connection 26 a, b, c, so that during the axial movement the brake base body 25 and thus the brake disc 13 are carried in the axial direction AR.

[0062] The Figure 3 shows an axial plan view of the brake unit 14 in a three-dimensional representation. However, the force distribution plate 24 is suppressed graphically so that the underlying components are visible. On the one hand, the annular piston 19 can be seen again, with the annular piston 19 being protected against penetrating contaminants by a seal 27. On the other hand, the screw connections 26 a, b, c can be seen, each of which is offset from each other by 120°.

[0063] To guide the brake base body 25 with the force distribution plate 24 and the annular piston 19 transversely to the axial direction AR, the brake unit 14 has a master guide 28 and an auxiliary guide 29. The master guide 28 and the auxiliary guide 29 are arranged coaxially to the screw connections 26a, b and / or also offset by 120°. There is no guide below the third screw connection 26c, but only a fixation between the force distribution plate 24 and the brake base body 25.

[0064] From a functional perspective, the radial play in the master guide 28 is smaller than in the auxiliary guide 29. This design is intended to help avoid overdefinition. This ensures that the brake base body 25 and thus the brake disc 13 can be moved without jamming. A further technical effect of the master guide 28 or auxiliary guide 29 is that torques introduced during the braking process about the main axis H can be transmitted from the brake disc 13 via the brake base body 25 to the housing 15. The radial play can be measured either rotationally symmetrically locally at the respective guides 28 or 29; alternatively, the radial play is measured in the circumferential direction around the main axis H.

[0065] The Figure 2shows a sectional view of the master guide 28, wherein the auxiliary guide 29 is of identical construction. The master guide 28 has a first axial section 30a, wherein the axial section 30a is formed integrally from the brake base body 25. On the radial inner side, a thread is provided into which a screw engages to form the screw connection 26a. The auxiliary guide 29 has a second axial section 30b, and the third screw connection 26c has a third axial section 30c, wherein the second and third axial sections 30b, c are constructed in the same way as the first axial section 30a, so that reference is made to its description.

[0066] The master guide 28 has a first guide section 31a, wherein the first guide section 31a accommodates the first axle section 30a. In particular, the first guide section 31a is arranged coaxially and concentrically with the first axle section 30a. The auxiliary guide 29 has a second guide section 31b, and the third screw connection 26c has a third guide section 31c. The second and third guide sections 31b, c are constructed in the same way as the first guide section 31a, so reference is made to the description of the latter.

[0067] The master guide 28 has a first guide sleeve 32a, wherein the first guide sleeve 32a is mounted on the first axle section 30a and provides a guide surface for the first guide section 31a. The auxiliary guide 29 has a second guide sleeve 32b, which is mounted on the second axle section 30b and provides a second guide surface for the second guide section 31a. The third screw connection 26c does not have a guide sleeve, so that the radial play can optionally be described as very large, in particular larger than the first and second radial play, or the third screw connection 26c does not implement any guiding function.

[0068] Thus, the torques introduced around the main axis H due to the braking process are transmitted from the brake disc 13 via the brake base body 25 and then via the master guide 28 and the auxiliary guide 29 into the housing 15. The housing 15 has a positive-locking section 35, which engages the wheel fork 6, so that the torque can be transferred to the wheel fork 6.

[0069] The brake unit 14 has a return device 33, wherein the return device 33 is formed by three return springs 34 a, b, c. In the Figure 2The first return spring 34a is shown, which is designed as a compression spring arranged coaxially with the master guide 18 and / or with the first axial section 30a and is compressed upon an axial movement of the brake disc 13 in the axial direction AR. The second and third return springs 34b,c are arranged coaxially with the auxiliary guide 29, coaxially with the second axial section 30b, and coaxially with the third axial section 30c, respectively, and are likewise compressed upon the axial movement of the brake disc 13 in the axial direction AR.

[0070] As soon as the hydraulic pressure in the hydraulic device 16 decreases, the brake disc 13 can be reset in the axial opposite direction GR by the spring force of the return springs 34 a, b, c.

[0071] Figure 4 shows a schematic sectional view of a wheel module 2 e.g. from the Figure 1as a further embodiment of the invention. Similar or identical reference numerals designate similar or identical components as in the preceding figures. In particular, reference is made to the preceding description for these components.

[0072] The wheel module 3 has the wheel axle 10, which defines a rotational axis D with its longitudinal axis. The wheel 3 is arranged coaxially to the rotational axis D on the wheel axle 10. The wheel axle 10 is fixed to the wheel fork 6, with the wheel rim 8 being rotatably mounted on the wheel axle 10 via two bearing devices 36, e.g., roller bearings.

[0073] To drive the wheel 3, the wheel module 2 has a drive device 37, e.g., an electric motor, integrated into the wheel rim 8. The drive device 37 has a stator 38 which is connected in a rotationally fixed manner to the wheel axle 10 and is arranged between the two bearing devices 36 in the axial direction with respect to the main axis. In addition, the drive device 37 has a rotor 39 which is connected in a rotationally fixed manner to the wheel rim 8. When the vehicle 1 is driving, a drive torque is generated between the stator 38 and the rotor 39, so that the wheel rim 8 is driven by the drive device 37 and the wheel 3 rotates about the main axis H.

[0074] The braking device 12 has an annular brake pad 40, in particular one that runs around the main axis H, as a rotating braking partner, and the brake disc 13, wherein the brake pad 40 and the brake disc 13 are arranged coaxially with one another with respect to the main axis H. The brake pad 40 is mounted on an axial end face of the wheel rim 8 in a rotationally fixed manner with respect to the main axis H, so that the brake pad 40 is carried by the wheel rim 8 during driving and rotates about the main axis H. The brake disc 13 is movable in the axial direction AR towards the brake pad 40 and away from the brake pad 40 in the opposite axial direction GR. In the direction of rotation around the main axis H, the brake disc 13 is rotationally fixedly coupled to the wheel axle 10.

[0075] The braking device 12 has a brake pad carrier 41, which supports the brake pad 40 on the wheel rim 8. For example, the brake pad 40 is applied to the brake pad carrier 41 in a materially bonded manner. The brake pad carrier 41 is annular, e.g., as a sheet metal ring, and is fastened to the wheel rim 2 via fastening means 42, in particular via a plurality of screws. The brake pad carrier 41 is arranged on the wheel rim 8 such that it is arranged coaxially and / or concentrically on the wheel rim 8.

[0076] When the brake device 12 is actuated, the brake disc 13 contacts the brake pad 40, so that the braking torque is generated by frictional engagement to decelerate the rotating wheel 3 through friction between the brake disc 13 and the brake pad 40. During heavy braking, high temperatures develop, particularly at the brake pad 40, which can lead to overheating of the drive device 37. Furthermore, the service life can be reduced because the materials in the drive device 37 age more rapidly at high temperatures.

[0077] In this regard, it is provided that the brake pad 40 and / or the brake pad carrier 41 are designed as a thermal insulator to insulate the wheel rim 8 and thus the drive device 37 from the heat generated by the braking friction. For this purpose, the brake pad 40 can, for example, comprise a friction agent made of an organic material, such as glass, rubber, or carbon fibers.

[0078] Because the brake pad 40 and / or the brake pad carrier 41 are arranged on the wheel rim 8, the braking device 12 can advantageously be designed to be particularly space-saving and particularly slim and narrow. Furthermore, due to the concentric design of the braking device 12, the braking device 12 can be easily adapted to a size of the wheel 3, in particular to a size of the wheel rim 8.

[0079] Between the wheel rim 8 or the drive device 11 and the brake body device 23, an interior space 43 is formed, which is arranged radially inside the brake disc 13 and / or the brake pad 40. In order to avoid heat build-up in this area, an axial opening 44 (see Figure 5 ) for air exchange.

[0080] The Figure 5shows a schematic three-dimensional view of the brake unit 14, wherein, on the one hand, the axial opening 44 can be seen. Furthermore, it can be seen that cooling structures 45 in the form of cooling fins are integrally incorporated into the brake base body 25 on the axial outer side, so that the surface of the brake base body 25 is enlarged and heat absorbed by the brake disc 13 or due to a heat buildup in the interior space 43 can be dissipated into the environment via thermal conduction. List of reference symbols

[0081] 1Vehicle 2Wheel module 3Wheel 4Rear wheel 5Vehicle frame 6Wheel fork 7Handlebar 8Wheel rim 9Tire 10Wheel axle 11Drive device 12Brake device 13Brake disc 14Brake unit 15Housing 16Hydraulic device 17Connection 18Annular space 19Annular piston 20Receiving section 21Outer wall 22Housing base body 23Brake body device 24Force distribution plate 25Brake base body 26a, b, cScrew connections 27Seal 28Master guide 29Auxiliary guide 30a, b, cAxle sections 31a, b, cGuide section 32a, bGuide sleeve 33Reset device 34a, b, cReset springs 35Form-locking section 36Bearing devices 37Drive device 38Stator 39Rotor 40Brake pad 41Brake pad carrier 42Screws 43Interior 44Axial opening 45Cooling structures

Claims

1. A wheel module (2) for a vehicle designed as an electric motorcycle or an electric scooter having a brake unit (14), having a housing (15), having a brake body device (23), wherein the brake body device (23) supports a stationary braking partner in a braking device (12) for the vehicle (1), wherein the housing (15) and / or the brake body device (23) define a main axis (H), having an actuator device for moving the brake body device relative to the housing (15) in order to generate a braking force, wherein the actuator device is configured for axial movement of the brake body device (23) having a brake disc (13), wherein the stationary braking partner is configured as the brake disc (13), wherein the wheel module (2) has a wheel (3) and a rotating braking partner of the braking device (12), wherein the rotating braking partner is non-rotatably connected to the wheel (3), characterised in that the actuator device is configured as a hydraulic device (16), wherein the hydraulic device (16) has an annular space (18) and an annular piston (19), wherein the annular space (18) and the annular piston (19) are formed circumferentially about the main axis (H), and in that the brake unit (14) has a guide device that guides the brake body device (23) in the radial direction when the brake body device (23) is moved axially relative to the housing (15), wherein the guide device has a master guide (28) and an auxiliary guide (29), which are arranged off-centre to the main axis (H) and are not placed coaxially to the main axis (H).

2. The wheel module according to claim 1, characterised in that the brake disc (13) is made from metal or ceramic.

3. The wheel module according to claim 1 or 2, characterised in that the brake disc (13) provides a braking surface, wherein the braking surface is formed as a circular ring surface and / or extends continuously in a direction of rotation to the main axis (H).

4. The wheel module (2) according to any one of the preceding claims, characterised in that the rotating braking partner is formed as a brake pad (40).

5. The wheel module (2) according to any one of the preceding claims, characterised by a drive device (11), wherein the drive device (11) is arranged in the wheel (3), in particular in a wheel rim (8) of the wheel (3).

6. A vehicle (1) having the wheel module (12) according to any one of claims 1 to 5, characterised in that the vehicle is designed as an electric motorcycle or as an electric scooter.