WO2021000987A1

WO2021000987A1 - Braking device for an electric bicycle and electric bicycle having the braking device

Info

Publication number: WO2021000987A1
Application number: PCT/DE2020/100462
Authority: WO
Inventors: Simon Ortmann; Philippe Wagner
Original assignee: Schaeffler Technologies AG & Co. KG
Priority date: 2019-07-04
Filing date: 2020-06-04
Publication date: 2021-01-07
Also published as: DE102019118026A1

Abstract

Various braking devices for braking a wheel on a bicycle, more particularly on an electrically assisted bicycle, are known. The problem addressed by the invention is that of proposing a braking device that is characterised by a compact design. To achieve this, the invention proposes a braking device (1) with a multiple-disc brake (3), wherein: the multiple-disc brake (3) has a fixed braking unit (4) and a rotating braking unit (5); the rotating braking unit (5) can be rotated about an axis of rotation D relative to the fixed braking unit (4), with an actuation apparatus (11) for actuating the multiple-disc brake (3); the actuation unit (11) has a piston housing (12) and an actuation piston (13), which can be axially displaced in the piston housing (12), for transferring an actuation force F1 to the multiple-disc brake (3). The rotating brake unit (5) has an outer support (9) and a plurality of brake discs (10) connected in a rotationally fixed manner to said outer support, and the fixed brake unit (4) has an inner support (7) and a plurality of brake pads (8) connected in a rotationally fixed manner to said inner support, at least one of the brake pads (8) being borne by the actuation piston (13).

Description

Brake device for an electric bicycle and electric bicycle with the brake device

The invention relates to a braking device for an electric bicycle with the features of the preamble of claim 1. Furthermore, the invention relates to an electric bicycle with the braking device.

Various braking devices for braking a wheel of bicycles, in particular of electrically assisted bicycles, are known. These braking devices are usually designed as rim brakes or disc brakes, such braking devices being arranged outside the wheel. There are also known braking devices which are integrated into the wheel, in particular in combination with a wheel hub motor.

The document DE 10 2010 032 853 A1, which probably forms the closest prior art, discloses a wheel hub motor with a stator that is connected to a wheel axle in a rotationally fixed manner, with a rotor for driving an impeller that rotates in a rotor housing relative to the stator the wheel axle is mounted, the rotor housing forming a hub housing and the motor being switchable to a generator mode in which it functions as a regenerative brake. A mechanical auxiliary brake device is also arranged in the rotor housing, which in addition to the regenerative brake can be activated via an actuating mechanism. In particular, the additional brake device is a magnetorheological brake device or a multi-plate clutch brake.

It is the object of the invention to propose a braking device of the type mentioned at the beginning, which is characterized by a compact design. It is also an object of the invention to propose an electric bicycle with the braking device. This object is achieved by a braking device with the features of claim 1 and by an electric bicycle with the features of claim 10. Preferred or advantageous embodiments of the invention emerge from the subclaims, the following description and the attached figures.

The invention relates to a braking device which is designed and / or suitable for an electric bicycle. In particular, the electric bicycle is designed as a bicycle with a pedal-assisting auxiliary drive, also known as a pedelec (“pedal electric cycle”). Alternatively, however, the electric bicycle can also be designed as a bicycle with an additional drive that is independent of pedaling, e.g. an e-bike or an e-scooter. The electric bicycle is particularly preferably designed as a four-wheel pedelec. In particular, however, an electric bicycle can also be understood to mean a multi-lane electromobile and / or an electrically powered light vehicle.

The braking device has a multi-disc brake, also known as a full disc brake. In particular, the multi-disc brake is and / or can be integrated into a wheel hub and / or a wheel hub drive of a wheel, preferably a front or rear wheel, of the bicycle. The multi-disc brake is preferably designed as a multi-disc brake. The multi-disc brake has a stationary brake unit, which is designed and / or suitable for fixing to a frame of the bicycle, in particular a wheel axle of the wheel. In particular, the stationary brake unit is indirectly connected in a rotationally fixed manner, e.g. via a stator of the wheel hub drive, or directly to the frame, in particular the wheel axle.

Furthermore, the multi-disc brake has a rotating brake unit which is designed and / or suitable for fixing to the wheel, in particular a hub housing of the wheel. In particular, the rotating brake unit is indirectly connected in a rotationally fixed manner, for example via a rotor of the wheel hub drive, or directly to the wheel, in particular the hub housing. In a ferry operation of the bicycle, the rotating brake unit is thus relative to the stationary brake unit by one Rotatable axis of rotation, the stationary brake unit preferably remaining stationary on the frame.

The braking device has an actuating device which is designed and / or suitable for actuating the multi-disc brake. In particular, the actuating device is arranged coaxially to the axis of rotation. The actuating device can preferably be actuated pneumatically or hydraulically. The actuating device has a piston housing and an actuating piston which can be axially displaced in the piston housing. The function of the actuating piston is to transfer an actuating force to the multi-disc brake when the braking device is actuated, so that when the braking device is actuated, a frictional connection is formed between the two brake units and a braking torque is transferred to the wheel. In particular, the actuating piston is operatively connected to the first and / or the second brake unit for this purpose.

When the multi-disc brake is closed, the actuating force is applied to the actuating piston in an axial direction, the actuating piston displacing or pressing the brake linings and the brake discs relative to one another in the axial direction so that the braking torque is generated. When the multi-disc brake is opened, the actuating force acting on the actuating piston is reduced or interrupted, the actuating piston automatically returning in an opposite axial direction, preferably via a restoring force acting on the actuating piston.

In the context of the invention, it is proposed that the rotating brake unit have an outer carrier and several brake disks connected to the outer carrier in a rotationally fixed manner. In particular, the outer carrier is non-rotatably connected to the wheel hub housing and / or to the rotor of the wheel hub drive. The rotating brake unit preferably has at least or precisely two of the brake disks. In addition, the stationary brake unit has an inner carrier and a plurality of brake linings connected to the inner carrier in a rotationally fixed manner. In particular, the inner carrier is connected to the wheel axle and / or the stator of the wheel hub drive in a rotationally test. The stationary brake unit preferably has at least or precisely two, in particular precisely four, of the brake linings.

In particular, the outer and the inner carrier are arranged coaxially and / or concentrically to one another with respect to the axis of rotation, the inner carrier being arranged radially inside the outer carrier. A brake disc is preferably arranged between two adjacent brake linings. In principle, the plurality of brake disks and the plurality of brake pads can be arranged one behind the other in an alternating sequence in the axial direction. Preferably, however, two brake pads are arranged between two adjacent brake disks, one brake pad being assigned to one brake disk and the other brake pad being assigned to the other brake disk.

It is also provided that at least or precisely one of the brake linings is carried by the actuating piston. The at least one brake lining is preferably connected to the actuating piston in a rotationally fixed manner. In particular, the at least one brake lining is connected indirectly, preferably via a transmission component, or directly to the actuating piston. In particular, the inner carrier is formed by the actuating piston, with preferably all or at least a large part of the brake linings of the multi-disc brake being fixed on the actuating piston in a rotationally fixed manner.

The advantage of the invention is that the arrangement of the at least one brake lining on the actuating piston means that the braking device can be made significantly more compact. By arranging several brake linings on the actuating piston, both a radial and an axial installation space can be saved, so that the braking device can be integrated particularly easily into the wheel hub or the wheel hub drive. In addition, a brake device with fewer components is created, which is characterized on the one hand by a simplified assembly and on the other hand by a more cost-effective fastening. In a specific embodiment of the invention it is provided that the piston housing is designed as an annular housing encircling the axis of rotation and the actuating piston is designed as an annular piston encircling the axis of rotation. In particular, the actuating device is designed in the manner of a concentric slave cylinder (CSC). For this purpose, the annular housing and the annular piston are arranged coaxially and / or concentrically to one another with respect to the axis of rotation. In particular, the annular piston is designed to be rotationally symmetrical with respect to the axis of rotation.

According to this embodiment, the ring housing defines an annular pressure space, in particular surrounding the axis of rotation, which is delimited in an axial direction with respect to the axis of rotation by the actuating piston. In an installation situation, the pressure chamber is in particular fluidly connected via a brake line to a master cylinder, which can preferably be actuated by a brake lever or brake pedal. The pressure chamber is particularly preferably filled with a fluid, in particular a hydraulic fluid. The actuating piston can have a sealing device which is designed and / or suitable for sealing off the pressure chamber in the axial direction. The sealing device preferably comprises a groove sealing ring which rests against the piston housing in a sealing manner around the circumference.

A braking device is thus proposed which is characterized by a particularly simple and compact actuating device. By designing the actuating device as a concentric slave cylinder, the actuating force can also be transmitted to the multi-disk brake evenly over the entire circumference.

In a further specification, provision is made for the stationary brake unit to have a support sleeve which is designed and / or suitable for radial support on the wheel axle of the bicycle. In particular, the support sleeve is designed in a rough shape as a cylinder sleeve. The support sleeve is at least preferred positively and / or non-positively connected to the wheel axis in the direction of rotation with respect to the axis of rotation.

According to this embodiment, the pressure chamber is delimited in a radial direction by the piston housing, in particular the ring housing, and in a radially opposite direction by the support sleeve, the actuating piston being guided by the support sleeve in the axial direction and in the axially opposite direction. In particular, the piston housing is supported radially and / or axially on the support sleeve. Preferably, the support sleeve for axially supporting the piston housing can have a radially outwardly directed end section, e.g. a locking flange, or a locking means arranged on the outer circumference, e.g. a locking ring. In particular, the piston housing can be connected to the support sleeve in a rotationally fixed manner, in particular via the end section designed as a securing flange.

Thus, a braking device is proposed which is characterized by a particularly compact structure. For this purpose, the support sleeve can combine several functions, such as piston guidance, delimitation of the pressure chamber, fastening and / or support of the piston housing, etc.

In a further development, it is provided that the actuating piston has a form-fit contour and the support sleeve has a counter-contour, which are in engagement with one another to introduce the braking torque into the support sleeve. The form-fit contour is preferably designed as an internal toothing arranged on an inner circumference of the actuating piston and the counter-contour is designed as an external toothing arranged on an outer circumference of the support sleeve. Particularly preferably, the inner and outer toothing are each designed as a longitudinal toothing aligned in the axial direction, the actuating piston and the support sleeve being rotationally fixed to one another via the longitudinal toothing and being displaceable relative to one another in the axial direction. It can optionally be provided that at least one of the brake linings is in direct engagement with the counter-contour of the support sleeve, in particular via the transmission component.

Optionally, it can be provided that a further counter-contour, in particular a further toothing, is arranged on an inner circumference of the support sleeve, which is designed and / or suitable for a rotationally fixed coupling with a corresponding form-fit contour of the wheel axle. In particular, the counter-contour and the further counter-contour can be formed by a common embossing, so that one counter-contour is formed by a negative of the other counter-contour.

A support sleeve is thus proposed which is expanded to include the function of the non-rotatable coupling. Due to the counter-contours introduced into the support sleeve, the support sleeve can be fixed particularly easily on the actuating piston or the wheel axle.

In an alternative development, it is provided that the actuating piston has a form-fitting contour and the piston housing has a counter-contour, which are in engagement with one another to introduce the braking torque into the piston housing. The form-fit contour is preferably designed as an internal toothing arranged on an inner circumference of the actuating piston and the counter-contour is designed as an external toothing arranged on an outer circumference of the piston housing, in particular the ring housing. Particularly preferably, the internal and external toothing are each designed as a longitudinal toothing aligned in the axial direction, the actuating piston and the piston housing being rotationally fixedly coupled to one another via the longitudinal toothing and being displaceable relative to one another in the axial direction. In this embodiment, the piston housing and the support sleeve are particularly preferably connected to one another in a rotationally fixed manner, so that the braking torque is introduced into the support sleeve via the piston housing. A piston housing is therefore proposed which is expanded to include the function of the non-rotatable coupling. The actuating piston can be attached to the piston housing in a particularly simple manner by virtue of the mating contour introduced into the piston housing.

In a further constructive implementation it is provided that the actuating piston has a radially outwardly directed pressing section. In particular, the pressing section is designed as a circular ring section directed radially outward. Optionally, the actuating piston has a piston section which is arranged inside the piston housing, the pressing section adjoining the piston section in the radial direction. The sealing device is preferably arranged at the end of the piston section.

According to this embodiment it is provided that the pressing section carries at least or exactly one of the brake linings. In the actuated state of the braking device, the actuating force is transmitted to the multi-disc brake via the pressing section. For this purpose, the brake lining arranged on the pressing section is arranged adjacent to one of the brake disks, with the actuating force being transmitted to the brake disks and the brake linings via the pressing section when the multi-disc brake is closed. Particularly preferably, the brake lining is positively and / or non-positively and / or cohesively connected to the pressing section. Alternatively, however, the brake lining can also be formed by a coating.

Thus, a braking device is proposed which is characterized by a compact actuating device with fewer components. The actuating force can be transmitted to the multi-disc brake directly via the actuating piston through the pressing section, so that, for example, an additional pressure plate or pressure pot can be dispensed with. Another constructive implementation provides that the actuating piston has a cylindrical support section. The carrier section preferably extends in the axial direction, in particular in the opposite direction to the piston section, outside the piston housing. The carrier section adjoins the piston section and / or the pressing section in the axial direction, the carrier section preferably being designed as a hollow cylinder.

According to this embodiment it is provided that the carrier section has a longitudinal toothing on its outer circumference, at least one of the brake linings being fixed on the carrier section in a rotationally fixed manner via the longitudinal toothing. In particular, the longitudinal toothing extends in the axial direction with respect to the axis of rotation, so that the at least one brake lining which is in engagement with the longitudinal toothing can be displaced in the axial direction. In principle, the brake lining can be designed as a friction disk which has a counter-toothing complementary to the longitudinal toothing on its inner diameter. However, the at least one brake lining is preferably connected to the carrier section via the transmission component, the transmission component having a counter-toothing complementary to the longitudinal toothing on an inner circumference. In particular, several, in particular exactly two, of the transmission components can be in engagement with the longitudinal teeth of the carrier section.

It is therefore a consideration of the invention to propose an actuating piston which also serves as an inner support for the brake linings. In addition, the proposed configuration can further reduce the radial installation space and the components of the braking device.

In a further specific embodiment it is provided that the stationary brake unit has a stop component, in particular arranged coaxially to the axis of rotation, which is designed and / or suitable for forming an end stop in the axial direction. When the brake is closed, the brake disks and the brake pads in between are preferably between the Stop component and the actuating piston, in particular the pressing portion, pressed together. The stop component is particularly preferably arranged in an end region of the support sleeve, the stop component being fixed to the support sleeve in the radial and / or axial direction. The stop component is preferably fixed to the support sleeve in the axial direction via a securing means arranged on the outer circumference, for example a securing ring or a screw nut. Particularly preferably, the stop component carries one of the brake linings, the brake lining being connected to the stop component in a form-fitting and / or non-positive and / or cohesive manner. Alternatively, however, the brake lining can also be formed by coating the stop component.

According to this embodiment it is provided that the stop component is non-rotatably connected to the actuating piston via the longitudinal toothing. The stop component preferably has a toothed section which is in engagement with the longitudinal toothing of the actuating piston. In addition, the stop component can have a support section for supporting on the support sleeve and a stop section for forming the end stop. The stop section is preferably directed radially outward in the manner of a flange. The support section and / or the toothed section are preferably directed radially inward in the manner of a flange. In particular, a spring device for generating the restoring force can be supported in the axial direction on the stop component, in particular the support section, and in the opposite axial direction on the actuating piston, in particular the carrier section.

A particularly robust and component-protecting braking device is therefore proposed, the stop component forming an end stop for the multi-disc clutch and at the same time transmitting the braking and / or drag torques acting on the stop component to the actuating piston via the toothed section. It can thus be ensured that the moments are not transferred to the securing device. In an alternative embodiment it is provided that the support sleeve has an end section which is designed and / or suitable for forming the end stop in the axial direction. When the brake is closed, the brake disks and the brake linings lying in between are preferably pressed together between the end section and the actuating piston, in particular the pressing section. The end section is preferably formed by primary shaping and / or by primary shaping of the support sleeve. The end section is particularly preferably designed as a flange directed radially outward. In particular, the end section carries one of the brake linings. In particular, the spring device can be supported in the axial direction on the end section and in the opposite axial direction on the actuating piston, in particular the carrier section.

A braking device is thus proposed which is characterized by a further reduction in the number of components, since the support sleeve also takes on the function of the end stop.

Another object of the invention relates to an electric bicycle with the braking device as already described above. The electric bicycle is particularly preferably designed as the pedelec, in particular as a four-wheel pedelec. The braking device, in particular at least the multi-disc brake, is particularly preferably integrated into a wheel of the bicycle. The bicycle can have several, preferably exactly two, in particular exactly four, of the braking devices, one braking device in each case being assigned to one of the wheels of the bicycle.

Further features, advantages and effects of the invention emerge from the following description of preferred exemplary embodiments of the invention and the accompanying figures. These show:

Figure 1 is a schematic sectional view of a braking device for an electric bicycle as a first embodiment; Figure 2 shows the braking device in the same representation as Figure 1 as a second embodiment of the invention.

Figures 1 and 2 each show a schematic sectional view of a braking device 1 in two different design variants. The braking device 1 is suitable for an electric bicycle, the braking device 1 being able to be integrated, for example, into a wheel hub and / or a wheel hub drive of a wheel 2 - only indicated schematically - of the electric bicycle. The braking device 1 has a diameter of less than 80 mm, for example. For example, the electric bicycle is designed as a four-wheel pedelec, the braking device 1 being designed accordingly for the weight of the four-wheel pedelec. The four-wheel pedelec has an empty weight of, for example, more than 150 kg, preferably more than 250 kg, in particular more than 350 kg.

The braking device 1 comprises a multi-disc brake 3, the multi-disc brake 3 having a fixed brake unit 4 and a rotating brake unit 5 which rotates about an axis of rotation D relative to the fixed brake unit 4 when the bicycle is being driven. The stationary brake unit 4 is fixed on a frame 6 - only indicated schematically - of the bicycle, for example on a wheel axle of the wheel 2. The rotating brake unit 4 is fixed directly on the wheel 2, for example on a wheel hub housing, or indirectly via the wheel hub drive, for example a rotor, on the wheel 2.

The stationary brake unit 4 has an inner carrier 7 as well as four brake linings 8, which are arranged on the inner carrier 7 in a rotationally fixed manner in relation to the axis of rotation D. The inner carrier 7 is non-rotatably connected to the frame 6, in particular the wheel axle, the inner carrier 7 remaining stationary on the frame when the wheel 2 is rotated. The rotating brake unit 5 has an outer carrier 9 and two brake disks 10, which are arranged on the outer carrier 9 in a rotationally fixed manner in relation to the axis of rotation D. The outer carrier 9 is rotatably connected to the wheel 2, the Outer carrier 9 is rotated when the wheel 2 is rotated about the axis of rotation D and takes the brake discs 10 with it in the direction of rotation. The inner carrier 7 is arranged radially inside the outer carrier 5, the brake disks 10 being arranged between the brake linings 8 in such a way that the two brake discs 10 are each arranged between two brake linings 8. For example, the brake pads 8 and the brake disks 10 are each designed as a circular ring disk encircling the axis of rotation D.

Furthermore, the braking device 1 has an actuating device 11 for actuating the multi-disc brake 3, the actuating device 11 being designed as a concentric slave cylinder (CSC). For this purpose, the actuating device 11 has a piston housing 12 designed as an annular housing and an actuating piston 13 designed as an annular piston, which is axially displaceable within the piston housing 12 with respect to the axis of rotation D. In addition, the stationary brake unit 4 has a support sleeve 14, which is designed, for example, similar to a CSC guide sleeve. The piston housing 12 is supported on an outer circumference of the support sleeve 14, the piston housing 12 and the support sleeve 14 jointly defining a pressure chamber 15. The pressure chamber 15 is delimited in a radial direction RR by the piston housing 12 and in a radial opposite direction RG by the support sleeve 14. In addition, the pressure chamber 15 is delimited in an axial direction AR by the actuating piston 13 and in an axially opposite direction AG by the piston housing 12. The pressure space 15 is designed as an annular space surrounding the axis of rotation D, which is filled with a fluid, e.g. a hydraulic fluid. For example, the pressure chamber 15 is fluidically connected to a master cylinder which can be actuated, for example, by a brake lever.

To seal the pressure chamber 15, the actuating piston 13 has a sealing device 16, which is mounted on the actuating piston 13 at the end. The sealing device 16 comprises a groove sealing ring 17 arranged coaxially with respect to the axis of rotation D and a sealing ring carrier 18, the groove sealing ring 17 being positively and / or non-positively locking via the sealing ring carrier 18, for example via a snap hook connection on which the actuating piston 13 is mounted. The groove sealing ring 17 rests in the radial direction RR on an inner circumference of the piston housing 12 and in the radial opposite direction RG on an outer circumference of the support sleeve 14 in a circumferentially sealing manner.

The actuating piston 13 has a piston section 19, a pressing section 20 and a carrier section 21, the sections 19, 20, 21 being connected to one another in one piece, for example made from a common semi-finished product. The piston section 19 protrudes into the piston housing 12 in the opposite axial direction AG, the sealing device 16 being arranged on the end face of the piston section 19. The pressing section 20 adjoins the piston section 19 in the radial direction RR, the pressing section 20 carrying one of the brake linings 8. The carrier section 21 adjoins the pressing section 20 or the piston section 19 in the axial direction AR, the carrier section 21 being designed as a hollow cylinder which is arranged coaxially to the axis of rotation D and takes over the function of the inner carrier 7.

The stationary brake unit 4 has a transmission component 22, the transmission component 22 carrying two of the brake linings 8. The brake linings are arranged on the transmission component 22 in such a way that one brake lining 8 faces the one brake disc 10 and the other brake lining 8 faces the other brake disc 10. For example, the transmission component 22 is designed as a driver disk which is arranged axially between the two brake disks 10. The carrier section 21 has a longitudinal toothing 23 on its radial outer side, the transmission component 22 being in engagement with the longitudinal toothing 23 via a corresponding counter-toothing 24. The transmission component 22 is thus non-rotatably connected to the actuating piston 13 in the direction of rotation about the axis of rotation D and is arranged on the carrier section 21 so as to be displaceable in the axial direction AR and the axially opposite direction AG.

The outer carrier 9 is designed, for example, in the manner of an outer disk carrier. The outer support 9 has a on its inner circumference Driving contour 11, for example in the form of a spline, the two brake disks 10 engaging with driving contour 11 in a rotationally fixed manner in the circumferential direction and displaceably in the axial direction with respect to the axis of rotation D.

In the first exemplary embodiment shown in FIG. 1, the stationary brake unit 4 has a stop component 25 which forms an end stop for the multi-disk brake 3 in the axial direction AR. The stop component 25 is fixed on the support sleeve 14 at the end of the support sleeve 14 via a securing means 26, for example a nut or another securing element. The stop component 25 has a radially inwardly directed support section 27 and a radially outwardly directed stop section 28, the stop section 28 forming the end stop and carrying one of the brake linings 8. Via the support section 27, the stop component 25 is supported on the support sleeve 14 in the radial and the opposite axial direction RG, AG and on the securing means 26 in the axial direction AR. In addition, the stop component has a toothed section 29 directed radially inward, the toothed section 29 being in engagement with the longitudinal toothing 23 of the carrier section 21.

In the first exemplary embodiment, the inner carrier 7 is formed by the actuating piston 13, in particular the carrier section 21, the actuating piston 13 being connected to the piston housing 12 in a rotationally fixed manner for this purpose. The actuating piston 13 has a form-locking contour 30, in particular molded onto the pressing section 20, and the piston housing 12 has a counter-contour 31 arranged on the radial outside, the form-locking contour 30 and the counter-contour 31 being positively engaged with one another in the direction of rotation about the axis of rotation D. For example, the form-fit contour 30 is designed as an internal tooth system and the mating contour 31 as an external tooth system.

The piston housing 12 can in turn be connected non-rotatably to the support sleeve 14 so that the torques transmitted to the piston housing 12 are introduced into the support sleeve 14. The support sleeve 14 has a radially outwardly directed End section 32, the piston housing 12 being supported in the opposite axial direction AG on the end section 32 and / or being connected to it in a rotationally test manner. In the first exemplary embodiment, the end section 32 is designed as a securing flange.

When the multi-disc brake 3 is actuated by the actuating device 11, a fluid pressure prevailing in the pressure chamber 15 is increased and transmitted as an actuating force F1 to the actuating piston 13, in particular the piston section 19. The actuating piston 13 is displaced in the axial direction AR, the pressing section 20 transmitting the actuating force F1 to the multi-disc brake 3, so that the two brake disks 10 are pressed together between the pressing section 20 and the stop component 28. The two brake disks 10 each form a frictional connection with the two associated brake linings 8, as a result of which a braking torque is generated between the two brake units 4, 5.

The transmission component 22 transfers the braking torque acting on the transmission component 22 to the carrier section 21 via the counter-toothing 24. To ensure that the braking torque is not transmitted to the securing means 26, the stop component 25 also transmits the applied braking torque to the carrier section via the toothed section 29 21 next. All of the braking and drag torques acting on the actuating piston 13 are introduced into the piston housing 12 via the interlocking interlocking contour 30 and the mating contour 31.

In order to ensure that the braking device 1 is opened, a spring device 33 in the form of a plate spring is attached between the stop component 25 and the actuating piston 13. The spring device 33 generates a restoring force F2 directed in the axially opposite direction AG, which, when the actuating device 11 is not actuated, pushes the actuating piston 13 back in the axially opposite direction AG, so that the frictional engagement between the brake disks 10 and the brake linings is canceled. In the first exemplary embodiment, as shown in FIG. 1, the actuating piston 13 thus performs several functions, mainly with its pressing section 20 being the pressure plate which presses the brake pads 8 against the brake disks 10 when the braking device 1 is actuated. In addition, the actuating piston 13 takes over all drag torques or braking torques acting on the stationary brake unit 4 and transmits them to the piston housing 12 and the support sleeve 14.

In the second exemplary embodiment shown in FIG. 2, the end section 32 of the support sleeve 14 serves to form the end stop for the multi-disk brake 3 in the axial direction AR. The end section 32 is designed as a stop flange which is integrally formed on the end of the support sleeve 14 and is directed radially outward and carries one of the brake linings 8. In the second exemplary embodiment, the actuating piston 13, in particular the carrier section 21, and the end section 32 together form the inner carrier 7.

In this variant, the actuating piston 13 is connected directly to the support sleeve 14 in a rotationally fixed manner. For this purpose, the carrier section 21 has the form-locking contour 30 on its inner circumference and the support sleeve 14 has the counter-contour 31 on its outer circumference, the form-locking contour 30 and the counter-contour 31 being in positive engagement with one another in the direction of rotation about the axis of rotation D. For example, the form-fit contour 30 is designed as an internal tooth system and the mating contour 31 as an external tooth system.

In the second exemplary embodiment, the support sleeve 14 also has a further counter-contour 34 on its inner circumference, which serves to transfer the braking and drag torques acting on the support sleeve 14 to the frame 6, in particular the wheel axle. For example, the further counter-contour 34 can be represented by embossed areas, a toothing or the like, the frame 6, in particular the wheel axle, having a form-locking contour configured in accordance with the further counter-contour 34. The stationary brake unit 4 has the securing means 26, the securing means 26 being designed, for example, as a securing ring in this exemplary embodiment. The securing means 26 is arranged at the end of the support sleeve 14 and secures the piston housing 12 in the opposite axial direction AG against being lost.

In addition, the stationary brake unit 4 in the second exemplary embodiment has an adjusting device 35 which can be used to set a defined air path for the actuating piston 13. The adjusting device 35 is designed, for example, as an adjusting nut which engages with the outside of the piston housing 12.

When the multi-disc brake 3 is actuated by the actuating device 11, the actuating force F1, as already described above, is transmitted to the actuating piston 13 and thus to the multi-disc brake 3, so that the two brake disks 10 are pressed together between the pressing section 20 and the end section 32 and that Braking torque is generated between the two brake units 4, 5. The transmission component 22 transfers the braking torque acting on the transmission component 22 via the counter-toothing 24 to the carrier section 21, whereby all braking or drag torques acting on the actuating piston 13 are introduced directly into the support sleeve 14 via the interlocking interlocking contour 30 and counter-contour 31 will. In addition, the braking torque acting on the end section 32 is introduced directly into the support sleeve 14.

In order to ensure that the braking device 1 is opened, the spring device 33 in the form of a helical compression spring is attached between the end section 32 and the actuating piston 13. As already described above, the spring device 33 generates the restoring force F2, which presses the actuating piston 13 back in the opposite axial direction AG in order to cancel the frictional engagement. The guide sleeve 14 thus takes on several functions in the second exemplary embodiment, as shown in FIG. 2, mainly it represents the end stop with the end section 32. In addition, the guide sleeve 14 takes over all drag torques or braking torques acting on the stationary brake unit 4 and transmits them to the Frame 6, especially the wheel axle.

In the two exemplary embodiments, a braking device 1

proposed, which can be easily integrated into the wheel hub of the bicycle. A particularly compact design of the braking device 1 is realized by the described embodiments, so that it is particularly

Can be integrated into wheel hubs or their drives to save space without changing their inner diameter.

Reference list

Braking device

wheel

Multi-disc brake

fixed brake unit

rotating brake unit

frame

Interior support

Brake pads

Balcony

Brake discs

Actuator

Piston housing

Actuating piston

Guide sleeve

Printing room

Sealing device

Groove sealing ring

Seal carrier

Piston section

Pressing section

Beam section

Transmission component

Spline

Mating teeth

Stop component

Securing means

Support section

Stop section 29 gear section

30 form fit contour

31 opposite contour

32 end section

33 Spring device

34 more contours

35 Adjustment device

AR axial direction

AG axial opposite direction

D axis of rotation

F1 actuation force

F2 restoring force

RR radial direction

RG radial opposite direction

Claims

1. Brake device (1) for an electric bicycle, in particular for a four-wheel pedelec, with a multi-disc brake (3), the multi-disc brake (3) having a fixed brake unit (4) for fixing to a frame (6) of the bicycle and a rotating one Brake unit (5) for fixing to a wheel (2) of the bicycle, the rotating brake unit (5) being rotatable relative to the stationary brake unit (4) about an axis of rotation (D), with an actuating device (11) for actuating the multi-disc brake (3), the actuating device (11) having a piston housing (12) and an actuating piston (13) which can be axially displaced in the piston housing (12) for transmitting an actuating force (F1) to the multi-disc brake (3), so that in an actuated state the Multi-disc brake (3) a frictional connection is formed between the two brake units (4, 5) and a braking torque is transmitted to the wheel (2), characterized in that the rotating brake unit (5) has a n outer carrier (9) as well as several brake disks (10) non-rotatably connected to the outer carrier (9) and that the stationary brake unit (4) has an inner carrier (7) and several brake linings (8) non-rotatably connected to the inner carrier (7), wherein at least one of the brake linings (8) is carried by the actuating piston (13).

2. Braking device (1) according to claim 1, characterized in that the piston housing (12) is designed as an annular housing encircling the axis of rotation (D) and the actuating piston (13) is designed as an annular piston encircling the axis of rotation (D), the annular housing being a annular pressure chamber (15) defined, which is limited by the actuating piston (13) in the axial direction.

3. Braking device (1) according to claim 1 or 2, characterized in that the stationary brake unit (4) has a support sleeve (14) for support on the frame (6), the pressure chamber (15) in a radial direction (RR) is limited by the piston housing (12) and in a radial opposite direction (RG) by the support sleeve (14) and wherein the actuating piston (13) in an axial direction (AR) and in an axially opposite direction (GR) by the support sleeve (14) is led.

4. Braking device (1) according to claim 3, characterized in that the actuating piston (13) has a form-fitting contour (30) and the support sleeve (14) has a mating contour (31), the form-fitting contour (30) and the mating contour (31) together are engaged, so that the braking torque is introduced into the support sleeve (14) via the actuating piston (13).

5. Braking device (1) according to one of claims 1 to 3, characterized in that the actuating piston (13) has a form-fitting contour (30) and the piston housing (12) has a mating contour (31), the form-fitting contour (30) and the mating contour (31) are in engagement with one another, so that the braking torque is introduced into the piston housing (12) via the actuating piston (13).

6. Braking device (1) according to one of the preceding claims, characterized in that the actuating piston (13) has a radially outwardly directed pressing section (20), the actuating force (F1) in the actuated state of the multi-disc brake (3) being transmitted to the multi-disc brake (3) via the pressing section (20).

7. Braking device (1) according to one of the preceding claims, characterized in that the actuating piston (13) has a cylindrical carrier section (21), wherein the carrier section (21) has a longitudinal toothing (23) on its outer circumference and wherein at least one of the brake linings (8) is non-rotatably supported on the carrier section (21) via the longitudinal toothing (23).

8. Braking device (1) according to claim 7, characterized in that the stationary brake unit (4) has a stop component (25) for forming an end stop in the axial direction, the stop component (25) on the actuating piston in a rotationally fixed manner via the longitudinal toothing (23) (13) is supported.

9. Braking device (1) according to claim 7, characterized in that the support sleeve (14) has an end section (32) for forming an end stop in the axial direction, the end section (32) being designed as a radially outwardly directed stop flange.

10. Electric bicycle with the braking device (1) according to one of the preceding claims.