Brake device

Abstract

The invention relates to a braking device (100) comprising at least: a stator part (10), a rotor part (50) rotatably arranged relative to the stator part (10), wherein the rotor part (50) and the stator part (10) are spaced apart concentrically from each other by an air gap (14), wherein the stator part (10) comprises an induction device (20), wherein the rotor part (50) comprises an excitation device (60) for generating a radially directed primary magnetic field, wherein the induction device (20) is configured to generate a secondary magnetic field (56) directed radially in the opposite direction to the primary magnetic field (54) at least in certain regions, wherein the rotor part (50) is axially displaceably mounted on the shaft (52) against a spring preload, wherein the induction device (20) and the excitation device (60) have at least partially inclined regions (88, 90) in the region of the air gap (14), wherein at least one friction element (78,82) is arranged between rotor part (50) and stator part (10), which, when the rotor part (50) is axially displaced against the spring preload, is in operative contact with the rotor part (50) and / or stator part (10).

Description

[0001] The invention relates to a braking device, in particular an eddy current braking device. State of the art

[0002] A braking device is installed in a vehicle, such as a motor vehicle, truck, or rail vehicle, and serves to reduce or limit the vehicle's speed. If the braking device is installed in a machine, it serves to reduce or limit the speed of moving machine parts.

[0003] Braking devices are divided according to their mode of operation into mechanical brakes, which are based on dissipating movement through friction between a fixed and a moving body, typically a disc, electric brakes, and magnetic brakes. Typical electric braking devices are electrodynamic braking devices, in particular eddy current brakes, electromotive brakes, and resistance brakes. With an electromotive brake, a drive motor acts as a generator during braking and is typically fed back into the vehicle's power supply. With an eddy current braking device, the eddy current effect is used, in which an electrically conductive material, typically a metal disc, is moved through a magnetic field, thereby inducing eddy currents in the material. These eddy currents, in turn, generate a magnetic field that counteracts the generated torque and thereby slows down the disc.The strength of the braking effect depends on several parameters, for example the conductivity of the brake disc, whereby the induced currents are directly proportional to the electrical conductivity of the material used.

[0004] A copper disc is therefore slowed down more effectively than a steel disc of the same construction. The strength of the braking effect also depends on the direction of the magnetic field, with the greatest braking effect being achieved when the magnetic field passes perpendicularly through the moving disc; on the air gap, whereby the larger the air gap, the smaller the maximum braking effect; on the shape of the disc, with discs with a circumferential comb-shaped structure or cracks having a reduced braking effect because the annular eddy currents can no longer develop over a large area; on the area under the excitation pole, whereby the smaller the area under the pole, the lower the braking effect; on the speed, with the braking effect strongly dependent on the relative speed between the field and the disc; and on the coil current, whereby the higher the current flowing through the magnet, the stronger the magnetic field and thus the braking force.

[0005] DE 102016108646 B4 describes an electrodynamic brake that uses an induction device characterized by both high permeability and high electrical conductivity. Due to the design of the induction device, these two properties are spatially separated from one another. The induction device comprises a structure made of several perforated plates extending at least substantially parallel to one another with aligned holes through which pins, in particular made of metal, extend. Disclosure of the invention

[0006] The object of the invention is to provide an improved braking device.

[0007] A further object of the invention is to provide a use for the improved braking device.

[0008] Another object of the invention is to provide a vehicle with an improved braking device.

[0009] The objects are achieved by the features of the independent claims. Advantageous embodiments and advantages of the invention emerge from the further claims, the description, and the drawings.

[0010] According to one aspect of the invention, a braking device, in particular an eddy current braking device, is proposed, which comprises at least one stator part and a rotor part arranged so as to be rotatable relative to the stator part about a rotational axis, with a shaft arranged on the rotational axis, wherein the rotor part and the stator part are arranged concentrically to one another with an air gap spaced from one another, wherein the stator part comprises an induction device designed to induce eddy currents by a magnetic field, wherein the rotor part comprises an excitation device designed to generate a primary magnetic field directed in the radial direction, wherein the induction device is designed to generate a secondary magnetic field directed at least partially opposite to the primary magnetic field in the radial direction as a result of a rotation of the rotor part about the rotational axis,The rotor part is mounted on the shaft for axial displacement against a spring preload, the induction device and the excitation device having, at least in part, particularly conical, slanted regions in the region of the air gap, and at least one friction element is arranged between the rotor part and the stator part, which friction element is operatively connected to the rotor part and / or the stator part upon axial displacement of the rotor part against the spring preload. The at least one friction element can be designed to produce an axial attraction force between the rotor part and the stator part when a primary magnetic field is generated. The rotor part is mounted for linear displacement, in particular. The rotor part is advantageously mounted non-rotatably on the shaft.

[0011] An eddy current braking device with radial magnetic flux guidance and integrated friction brake can advantageously be implemented.

[0012] The rotor section can be advantageously implemented as an internal rotor within the stator section, allowing for a smaller design. The radial flux guidance allows for increased power density.

[0013] In the case of an external rotor, the stator-rotor arrangement can be reversed, with the stator section located inside the rotor. Accordingly, all arrangements, geometries, and orientations, such as pole elements directed radially outward, are also possible in reverse.

[0014] By creating a skew between the stator and rotor parts, the magnetic flux density can generate an axial attraction force. This causes an axial displacement of the rotor part after overcoming the preload force of the spring element, so that contact between the friction pair of the two friction elements can occur between the stator and rotor parts. This can generate an additional friction torque. This compensates for a disadvantage inherent in the purely electrodynamic eddy-current brake and generates a torque that can brake the eddy-current brake to a standstill.

[0015] Radial flux guidance avoids typical problems of axial flux machines, where the maximum speed is limited by the yield point or tensile strength of the material due to the large rotor diameter, the high rotor mass and the typical disk shape. Likewise, the large rotor diameter in axial flux machines causes deformation in the axial direction at high speeds and thus a significant change in the air gap. In the worst case, this increases the air gap. As a result, the power density is reduced at high speeds. The magnetic properties are also changed, and the braking device behaves differently than a (design) simulation model on which the device is based. The predictive power of the model is limited. Furthermore, axial flux machines require more manufacturing effort for the electrical lamination stacks, since a single lamination stack consists of several electrical laminations of different sizes.In addition, the rotors are made of solid material with a correspondingly high machining effort.

[0016] According to a favorable embodiment of the braking device, the shaft can have a shoulder, with a spring element arranged between the shoulder and the rotor part to generate the spring preload. The generated spring preload can advantageously keep the stator part and the rotor part at a distance when the braking device is not activated, so that no frictional force is present.

[0017] According to a favorable design of the braking device, the shaft can have a stop to limit the axial displacement of the rotor part due to the spring preload. This advantageously allows the stator part and the rotor part to be kept at a distance when the braking device is not activated, so that no frictional force is present.

[0018] According to a favorable embodiment of the braking device, frictional contact can be formed between an axially aligned friction element, in particular a brake disc, arranged on the rotor part and a friction element, in particular a brake pad, arranged on the stator part. This allows a friction pairing to be realized during operation.

[0019] According to a favorable design of the braking device, the helix angle of the helix areas relative to the rotational axis can be adjusted according to a predetermined braking torque. Due to the helix, an axial attraction force can be generated due to the magnetic flux density, which causes an axial displacement of the rotor part after overcoming the preload force of the spring element, so that contact of the friction pair of the friction elements between the stator part and the rotor part can occur. This can generate an additional friction torque. This compensates for a disadvantage inherent in the purely electrodynamic eddy-current brake and generates a torque that can brake the eddy-current brake to a standstill.

[0020] According to a favorable embodiment of the braking device, the induction device can comprise a substantially annular base body with a plurality of pole elements directed radially toward the rotor part and an electrically conductive element that at least partially encloses the pole elements. This advantageously allows the realization of an eddy current brake with radial magnetic flux guidance.

[0021] According to a favorable design of the braking device, the base body can comprise an electrical lamination stack with electrical laminations stacked in the axial direction, or it can be designed as an electrical lamination stack with electrical laminations stacked in the axial direction. Electrical laminations are relatively easy to manufacture. This can advantageously reduce the disruptive skin effect.

[0022] According to a favorable embodiment of the braking device, the electrically conductive element can comprise individual electrically conductive sheets that enclose the pole elements and are arranged substantially concentrically to one another in the radial direction. The radial spacing between the individual electrical sheets allows for favorable flow of coolant in the axial direction.

[0023] In a favorable design of the braking device, the electrically conductive individual sheets can be ring-shaped. This allows for a simple construction. The radial spacing between the individual electrical sheets allows for favorable flow of coolant in the axial direction.

[0024] According to a favorable embodiment of the braking device, the electrically conductive individual sheets can be designed as sheet metal strips, wherein adjacent sheet metal strips, in particular at end faces, are electrically conductively connected to one another, in particular soldered or welded.

[0025] According to a favorable embodiment of the braking device, the electrically conductive element can comprise at least one electrically conductive sheet metal strip having a plurality of through-openings for the plurality of pole elements. The electrically conductive sheet metal strip is applied to the plurality of pole elements in a spiral shape around the rotational axis with several turns. The radial spacing between the individual electrical sheets allows for favorable flow of a coolant in the axial direction.

[0026] This allows multiple layers of laminations to be arranged radially one above the other. The radial spacing between the individual laminations allows for favorable flow of coolant in the axial direction. This facilitates good heat transfer, thus advantageously reducing thermal stress during operation of the braking device.

[0027] According to a favorable embodiment of the braking device, the electrically conductive element can comprise an electrically conductive foam which encloses the plurality of pole elements.

[0028] For the purposes of the present invention, an electrically conductive foam is understood to be a porous structure permeated by a multitude of pores. Pores form hollow bodies and / or cavities within the structure, which are separated from one another by webs, particularly solid webs. The porous structure is, in particular, a two-phase system formed from a solid and a gaseous phase and / or a solid and a liquid phase.

[0029] The metallic electrically conductive material of the porous structure has in particular an electrical conductivity of at least 20·10 6 S / m (relative to room temperature) and is, for example, a metal.

[0030] The porous structure can be manufactured in just a few steps. Properties of the porous structure, such as the size of the pores or the width of the webs, can be easily adapted to the requirements of a specific application. Furthermore, assembly steps can be reduced. For example, after the stator laminated core is completed, it can be directly encased in metal foam without the need for prefabrication of the metal foam.

[0031] The porous structure exhibits particularly good mechanical properties, such as high specific strength and high specific stiffness. This allows for a smaller and lighter design of the braking device according to the invention.

[0032] Advantageously, the porous structure may be an aluminum foam or a copper foam or a magnesium foam or comprises an aluminum foam or a copper foam or a magnesium foam.

[0033] Advantageously, the porous structure can be open-pored. Open-pored means that the pores and / or cavities of the porous structure communicate with each other and with the environment. In particular, a void volume of the porous structure is formed by the sum of the pores and / or cavities that communicate with each other and with the environment.

[0034] According to a favorable design of the braking device, the axial side surfaces of the pole elements can be inclined at a helical angle counter to the axial direction. This can reduce cogging torque.

[0035] According to a favorable embodiment of the braking device, the excitation device can comprise a base excitation body enclosing the shaft and having a plurality of excitation pole elements directed radially toward the stator part. In particular, each excitation pole element can comprise an electrical excitation coil. In this way, the eddy-current brake can advantageously be implemented in the form of an asynchronous machine with 100% slip and constant current supply.

[0036] According to a favorable design of the braking device, the exciter base body can comprise a second electrical sheet stack with individual sheets stacked in the axial direction or be designed as a second electrical sheet stack with individual sheets stacked in the axial direction. In this way, the eddy current brake can advantageously be implemented as an asynchronous machine with 100% slip and constant current supply.

[0037] According to a favorable design of the braking device, the electrical excitation coils can be designed for electrical coupling to an electrical control unit. This allows the braking effect of the eddy-current brake to be suitably controlled and / or regulated.

[0038] According to a favorable design of the braking device, the number of pole elements directed radially toward the rotor part and the number of excitation pole elements directed radially toward the stator part can differ by no more than 50%. This allows a particularly favorable braking effect to be achieved.

[0039] According to a favorable embodiment of the braking device, the electrically conductive element can have one or more coolant paths through which a coolant flows.

[0040] This allows for axial flow of coolant. This provides the advantage of optimal heat transfer. This minimizes thermal stress on the braking system. This has the advantage of improving braking system safety.

[0041] According to a favorable embodiment, the braking device can comprise one or more slip-ringless rotary transformers for transmitting an excitation current to the excitation device arranged on the rotor part.

[0042] The radial flux guide allows for a higher power density than eddy-current braking devices with axial flux guide. The additional mechanism consisting of the spring element and the friction element allows torque to be generated until the system comes to a standstill. This allows the system to be braked effectively to a standstill.

[0043] According to a further aspect, a use of a braking device, in particular an eddy current braking device, is proposed, wherein the braking device can be installed in a road vehicle, in particular a motor vehicle or lorry or a rail vehicle.

[0044] Alternatively, the braking device, in particular eddy current braking device, can be used in test benches for engines, in particular combustion engines and turbines.

[0045] According to a further aspect, a vehicle is proposed that includes a braking device, in particular an eddy-current braking device. The vehicle can be a road vehicle or a rail vehicle. The radial flux guidance allows a higher power density to be achieved than with eddy-current braking devices with axial flux guidance. The additional mechanism consisting of the spring element and the friction element allows a torque to be generated until the vehicle comes to a standstill. This allows the vehicle to be advantageously braked to a standstill.

[0046] The vehicle can be a motor vehicle, such as a passenger car or a truck. The vehicle can also be a rail vehicle, such as a train.

[0047] The braking device can be provided as a second braking device in addition to a mechanical braking device. The eddy-current braking device can be integrated into a drive train of the vehicle. Alternatively, the eddy-current braking device can be arranged on a second drive shaft and perform the function of a braking device.

[0048] An advantage of the proposed braking device installed in the vehicle is that the vehicle can be braked to a complete stop. This can be achieved through the interaction of the spring preload device and the friction element, which form an integrated friction brake.

[0049] According to a further aspect, a vehicle test bench is proposed that includes a braking device, in particular an eddy current braking device. This enables a test bench with high power density, which preferably exclusively provides a braking torque. The braking device with radial flux guidance advantageously enables improved power density of the braking device. This allows for optimized installation space and axial coolant flow. drawing

[0050] Further advantages will become apparent from the following description of the drawings. The figures illustrate exemplary embodiments of the invention. The figures, the description, and the claims contain numerous features in combination. Those skilled in the art will also expediently consider the features individually and combine them into useful further combinations.

[0051] Examples include: Fig. 1 is an isometric view of a braking device with radial flux guidance and integrated friction brake according to an embodiment of the invention; Fig. 2 a longitudinal section through one side of the braking device Fig. 1; Fig. 3 a schematic representation of a section of the braking device with a radially directed magnetic field; Fig. 4 a plan view of a cross section of the rotor part and stator part of the braking device with a radially directed magnetic field. Embodiments of the invention

[0052] In the figures, components of the same type or function similarly are designated by the same reference numerals. The figures are merely examples and are not to be construed as limiting.

[0053] Before describing the invention in detail, it should be noted that it is not limited to the specific components of the device, as these components may vary. The terms used herein are intended solely to describe particular embodiments and are not intended to be limiting. Furthermore, when the singular or indefinite articles are used in the description or claims, this also refers to the plural of these elements, unless the overall context clearly indicates otherwise.

[0054] The directional terminology used below, including terms such as "left," "right," "top," "bottom," "before," "behind," "after," and the like, is intended solely to enhance understanding of the figures and is in no way intended to limit the scope of the invention. The components and elements depicted, as well as their design and use, may vary according to the considerations of a person skilled in the art and may be adapted to specific applications.

[0055] Fig. 1 shows a schematic representation of a braking device 100 in the form of an eddy current braking device with radial flux guidance. The braking device 100 comprises a stator part 10 and a rotor part 50 arranged so as to be rotatable relative to the stator part 10 about a rotational axis 12. The rotor part 50 has a shaft 52 arranged in the rotational axis 12. The rotor part 50 is arranged radially within the stator part 10 with an air gap 14 spaced therefrom. The stator part 10 comprises an induction device 20, which is designed to induce eddy currents through a magnetic field. The rotor part 50 comprises an excitation device 60, which is designed to generate a primary magnetic field 54 directed in the radial direction 16 (shown in Fig. 3). The induction device 20 is designed to generate a secondary magnetic field 56 (shown in Fig. 3) trained.

[0056] In the exemplary embodiments, the braking device 100 is illustrated as an internal rotor, in which the rotor part 50 is arranged radially within the stator part 10. If the braking device 100 is designed as an external rotor, the stator-rotor arrangement can be reversed, with the stator part 10 arranged within the rotor part 50. Accordingly, all arrangements, geometries, and orientations are also possible in reverse, e.g., pole elements directed radially outward.

[0057] The induction device 20 has a substantially annular base body 22, which comprises an electrical lamination stack 26 with electrical laminations 28 stacked in the axial direction 12 or is designed as an electrical lamination stack 26 with electrical laminations 28 stacked in the axial direction 12. The electrically conductive element 30 comprises electrically conductive individual laminations 32, which enclose the pole elements 24 and are arranged substantially concentrically to one another in the radial direction 16. The electrically conductive individual laminations 32 can be annular.

[0058] The electrically conductive individual sheets 32 are designed as sheet metal strips 34, wherein adjacent sheet metal strips 34, in particular at end faces 36, are electrically conductively connected to one another, in particular soldered or welded.

[0059] The base body 22 comprises a plurality of radially inwardly directed pole elements 24 and the electrically conductive element 30, which encloses the pole elements 24 at least in regions.

[0060] Fig. 2 shows a longitudinal section through one side of the braking device 100 from Fig. 1. The braking device 100 with radial flux guidance has an integrated friction brake. The stator part 10 is arranged at a distance from the rotor part 50, with the air gap 14 in between.

[0061] The rotor part 50 is mounted on the shaft 52 so that it can be axially displaced, in particular linearly displaced, against a spring preload. The induction device 20 and the excitation device 60 have, at least in some areas, in particular conical, beveled regions 88, 90 in the region of the air gap 14. At least one friction element 78, 82 is formed between the rotor part 50 and the stator part 10, which friction element 78, 82 is operatively connected to the rotor part 50 and / or the stator part 10 upon axial displacement of the rotor part 50 against the spring preload. The friction elements 78, 82 are designed to produce an axial attraction force 58 between the rotor part 50 and the stator part 10 when the primary magnetic field 54 is generated. The friction elements 78, 82 form a brake pad 79. In this way, an integrated friction brake is formed in the braking device 100.

[0062] The rotor part 50 has the helix area 90. The stator part 10 has the helix area 88. A helix angle 91 (shown in Fig. 3) the skew areas 88, 90 are adjusted against the rotation axis 12 according to a predetermined braking torque.

[0063] The friction element 78 and the brake pad 79 are arranged adjacent to the induction device 20 with the electrically conductive element 30. The shaft 52 has a shoulder 84, with the spring element 76 for generating the spring preload being arranged between the shoulder 84 and the rotor part 50. Furthermore, the shaft 52 has a stop 86 for limiting the axial displacement of the rotor part 50 due to the spring preload. The shoulder 86 has the function of limiting the displacement path of the rotor part 50 due to the spring preload. The beveled region 88 and the beveled region 90 each form a conical shape for the electrical sheet stack 26 of the stator part 10 and the electrical sheet stack 68 of the rotor part 50. The respective conical shape generates an axial magnetic attraction force. A vertical height of the formed cone, the air gap 14 and the strength of the current supply determine the size of the magnetic attraction force.

[0064] A frictional contact 98 is formed between the axially aligned friction element 82, in particular brake disc 83, arranged on the rotor part 50 and the friction element 78, in particular brake pad 79, arranged on the stator part 10.

[0065] Due to the skew between stator part 10 and rotor part 50, an axial attraction force can be generated due to the magnetic flux density, which causes an axial displacement of rotor part 50 after overcoming the preload force of spring element 76, so that contact can occur between the friction pair of friction elements 78, 82. This can generate an additional friction torque. Thus, a disadvantage inherent in the purely electrodynamic eddy-current brake can be compensated for and a torque can be generated, allowing the eddy-current brake to be braked to a standstill.

[0066] Fig. Figure 3 shows a schematic representation of a section of the braking device 100 with the radially directed magnetic field. The stator part 10, which has the base body 22 and the induction device 20 with the electrically conductive element 30, is arranged with the air gap 14 at a distance from the rotor part 50, which forms the excitation device 60. The excitation device 60 has the beveled region 88. The induction device 20, in particular the electrical sheet stack 26, has the beveled region 90. A bevel angle 91 is formed between an outer radius 94 and the beveled region 90.

[0067] In the enlarged section on the left side of the drawing plane Fig. 3 shows an enlarged view of the beveled region 88, the air gap 14, and the beveled region 90 together with the primary magnetic field 54, the secondary magnetic field 56, and the axial attractive force 58. The primary magnetic field 54 runs perpendicularly in the air gap 14 between the beveled regions 88 and 90. Reference numeral 59 denotes the direction of a generated magnetic force 59. The enlarged section shows a breakdown of the generated magnetic force 59 into its components, namely the attractive force 58 in the axial direction and the attractive force 57 in the radial direction. The axial attractive force 58 creates frictional contact 98 between the friction element 78, in particular the brake pad 79, and the friction element 82, in particular the brake disc 83.

[0068] The spring element 76 is arranged between the shoulder 84 and the excitation device 60. On the other side of the excitation device 60, the stop 86 is shown, which prevents the displacement of the rotor part 50 from becoming excessive due to the spring preload of the spring element 76 in the non-activated state of the braking device 100.

[0069] An outer radius 94 and an inner radius 92, which represent a radial extension of the helical region 90 of the stator part 10, can advantageously be selected so that excessive attractive forces are not generated. The attractive forces can be adjusted by selecting the radius 92, 94 such that a sufficient braking torque is generated. The spring element 76 can be dimensioned accordingly smaller. A favorable design is when the outer radius 94 is larger than the inner radius 92 and the inner radius 92 is larger than the radius of the shaft 52.

[0070] In a further advantageous embodiment, the electrically conductive element 30 can comprise at least one electrically conductive sheet metal strip 38, which has a plurality of through-openings 40 for the plurality of pole elements 24. The electrically conductive sheet metal strip 38 can be applied to the plurality of pole elements 24 in a spiral shape around the rotational axis 12 with a plurality of turns. As a result, a plurality of sheet metal layers 42 can be arranged one above the other in the radial direction 16. In the illustration in the Fig. 1 and Fig. 2, the metal strip 38 is not visible and is in the Fig. 4 in a plan view of a cross section through stator part 10 and rotor part 20 of the braking device 100.

[0071] In a further embodiment, the electrically conductive element 30 may comprise an electrically conductive foam 44 that surrounds the plurality of pole elements 24. The electrically conductive foam 44 may advantageously comprise the elements aluminum or copper or a compound with copper and / or aluminum. In the illustration in the Fig. 1 and Fig. 2 the foam 44 is not visible.

[0072] For the purposes of the present invention, an electrically conductive foam is understood to be a porous structure permeated by a multitude of pores. Pores form hollow bodies and / or cavities within the structure, which are separated from one another by webs, particularly solid webs. The porous structure is, in particular, a two-phase system formed from a solid and a gaseous phase and / or a solid and a liquid phase.

[0073] The metallic electrically conductive material of the porous structure has in particular an electrical conductivity of at least 20·10 6 S / m (relative to room temperature) and is, for example, a metal.

[0074] The porous structure can be manufactured in just a few steps. Properties of the porous structure, such as the size of the pores or the width of the webs, can be easily adapted to the requirements of an application. Furthermore, assembly steps can be reduced. The porous structure exhibits particularly good mechanical properties, such as high specific strength and high specific stiffness. This enables a smaller and lighter design of the braking device according to the invention.

[0075] Advantageously, the porous structure may be an aluminum foam or a copper foam or a magnesium foam or comprises an aluminum foam or a copper foam or a magnesium foam.

[0076] Advantageously, the porous structure can be open-pored. Open-pored means that the pores and / or cavities of the porous structure communicate with each other and with the environment. In particular, a void volume of the porous structure is formed by the sum of the pores and / or cavities that communicate with each other and with the environment.

[0077] The pole elements 24 can have axial side surfaces 46 which run at a helix angle 48 against the axial direction 12.

[0078] The excitation device 60 comprises an excitation base body 62 surrounding the shaft 52 with a plurality of radially outwardly directed excitation pole elements 64, each of which has an electrical excitation coil 66.

[0079] The exciter base body 62 comprises a second electrical sheet stack 68 with individual sheets stacked 12 in the axial direction or is designed as a second electrical sheet stack 68 with individual sheets stacked 12 in the axial direction.

[0080] A number of radially inwardly directed pole elements 24 and a number of radially outwardly directed excitation pole elements 64 differ by a maximum of 50%.

[0081] The electrically conductive element 30 has one or more coolant paths through which a coolant 70 flows.

[0082] The braking device 100 comprises one or more slip-ringless rotary transformers for transmitting an excitation current to the excitation device 60 arranged on the rotor part 50.

[0083] The electrical excitation coils 66 are designed for electrical coupling to an electrical control unit 80.

[0084] The braking device 100 can be arranged on an axle of a drive train or an axle of the wheels of a vehicle. In particular, the braking device can be arranged on a rear axle of the vehicle. Reference symbol 10 Stator part 12 axis of rotation 14 Air gap 16 radial direction 20 Induction device 22 basic bodies 24 pole element 26 Electrical sheet package 28 Electrical sheet 30 electrically conductive element 32 single sheets 34 metal strips 35 electrically conductive connection 36 front side 38 electrically conductive sheet metal strips 40 Feed-through opening 41 distance 42 sheet layers 44 electrically conductive foam 46 side surface 48 helix angles 50 rotor part 52 Wave 54 primary magnetic field 56 secondary magnetic field 57 radial tightening force 58 axial tightening force 59 Magnetic force 60 Excitation device 62 pathogen base bodies 64 Excitation pole element 66 Excitation coil 68 second electrical sheet package 70 coolant 72 Excitation current 74 Eddy current 76 spring element 78 Friction element 79 brake pad 80 control unit 82 Friction element 83 brake disc 84 paragraph 86 stop 88 Bevel area 90 bevel range 91 Helix angle 92 inner radius 94 Outer radius 96 Shift direction 98 Friction contact 100 braking device QUOTES CONTAINED IN THE DESCRIPTION

[0000] This list of documents submitted by the applicant was generated automatically and is included solely for the convenience of the reader. This list is not part of the German patent or utility model application. The DPMA assumes no liability for any errors or omissions. Cited patent literature

[0000] DE 102016108646 B4

[0005]

Claims

[1] Braking device (100), in particular eddy current braking device, comprising at least a stator part (10), a rotor part (50) arranged to rotate relative to the stator part (10) about a rotational axis (12), with a shaft (52) arranged in the rotational axis (12), wherein the rotor part (50) and the stator part (10) are arranged concentrically to each other with an air gap (14) spaced from each other, wherein the stator part (10) comprises an induction device (20) which is designed to induce eddy currents through a magnetic field, wherein the rotor part (50) comprises an excitation device (60) which is designed to generate a primary magnetic field (54) directed in the radial direction (16), wherein the induction device (20) is designed to generate a secondary magnetic field (56) which is directed at least partially opposite to the primary magnetic field (54) in the radial direction (16) as a result of a rotation of the rotor part (50) about the axis of rotation (12), wherein the rotor part (50) is mounted on the shaft (52) so as to be axially displaceable against a spring preload, wherein the induction device (20) and the excitation device (60) have at least partially, in particular conical, bevel areas (88, 90) in the area of the air gap (14), wherein at least one friction element (78, 82) is arranged between the rotor part (50) and the stator part (10), which friction element is in operative connection with the rotor part (50) and / or the stator part (10) upon axial displacement of the rotor part (50) against the spring preload. [2] Braking device according to claim 1, wherein the shaft (52) has a shoulder (84), wherein a spring element (76) for generating the spring preload is arranged between the shoulder (84) and the rotor part (50). [3] Braking device according to claim 1 or 2, wherein the shaft (52) has a stop (86) for limiting the axial displacement of the rotor part (50) due to the spring preload. [4] Braking device according to one of the preceding claims, wherein a friction contact (98) is formed between an axially aligned friction element (82), in particular a brake disc (83), arranged on the rotor part (50), and a friction element (78), in particular a brake pad (79), arranged on the stator part (10). [5] Braking device according to one of the preceding claims, wherein a helix angle (91) of the helix regions (88, 90) against the axis of rotation (12) is set in accordance with a predetermined braking torque. [6] Braking device according to one of the preceding claims, wherein the induction device (20) comprises a substantially annular base body (22) with a plurality of pole elements (24) directed radially towards the rotor part (50) and an electrically conductive element (30) which encloses the pole elements (24) at least in regions. [7] Braking device according to claim 6, wherein the base body (22) comprises an electrical sheet stack (26) with electrical sheets (28) stacked in the axial direction (12) or is designed as an electrical sheet stack (26) with electrical sheets (28) stacked in the axial direction (12). [8] Braking device according to claim 6 or 7, wherein the electrically conductive element (30) comprises electrically conductive individual sheets (32) which enclose the pole elements (24) and are arranged substantially concentrically to one another in the radial direction (16). [9] Braking device according to claim 8, wherein the electrically conductive individual sheets (32) are annular. [10] Braking device according to claim 8, wherein the electrically conductive individual sheets (32) are designed as sheet metal strips (34), wherein adjacent sheet metal strips (34), in particular at end faces (36), are electrically conductively connected to one another, in particular soldered or welded. [11] Braking device according to claim 6 or 7, wherein the electrically conductive element (30) comprises at least one electrically conductive sheet metal strip (38) which has a plurality of through openings (40) for the plurality of pole elements (24), wherein the electrically conductive sheet metal strip (38) is applied to the plurality of pole elements (24) in a spiral manner around the axis of rotation (12) with a plurality of turns. [12] Braking device according to claim 6 or 7, wherein the electrically conductive element (30) comprises an electrically conductive foam (44) which encloses the plurality of pole elements (24). [13] Braking device according to one of claims 6 to 12, wherein axial side surfaces (46) of the pole elements (24) extend with a helix angle (48) against the axial direction (12). [14] Braking device according to one of the preceding claims, wherein the excitation device (60) comprises an excitation base body (62) enclosing the shaft (52) with a plurality of excitation pole elements (64) directed radially towards the stator part (10), in particular of which each excitation pole element (64) comprises an electrical excitation coil (66). [15] Braking device according to claim 14, wherein the exciter base body (62) comprises a second electrical sheet stack (68) with individual sheets stacked in the axial direction (12) or is designed as a second electrical sheet stack (68) with individual sheets stacked in the axial direction (12). [16] Braking device according to claim 14 or 15, wherein the electrical excitation coils (66) are designed for electrical coupling to an electrical control unit (80). [17] Braking device according to one of claims 6 to 16, wherein a number of pole elements (24) directed radially towards the rotor part (50) and a number of excitation pole elements (64) directed radially towards the stator part (10) differ by at most 50%. [18] Braking device according to one of the preceding claims, wherein the electrically conductive element (30) has a coolant reservoir or a plurality of coolant paths provided for the flow through of a coolant (70). [19] Braking device according to one of the preceding claims, comprising one or more slip-ringless rotary transformers for transmitting an excitation current to the excitation device (60) arranged on the rotor part (50). [20] Use of a braking device (100), in particular an eddy current braking device according to one of claims 1 to 19, in a road vehicle, in particular a motor vehicle or lorry, or a rail vehicle. [21] Vehicle with a braking device (100) according to one of claims 1 to 19. [22] Vehicle test bench with a braking device (100) according to one of claims 1 to 19 for providing a braking torque.

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