EP4078331A1

EP4078331A1 - Magnetorheological braking device

Info

Publication number: EP4078331A1
Application number: EP20839297.7A
Authority: EP
Inventors: Stefan Battlogg
Original assignee: Inventus Engineering GmbH
Current assignee: Inventus Engineering GmbH
Priority date: 2019-12-18
Filing date: 2020-12-18
Publication date: 2022-10-26
Also published as: US20230102886A1; US11360503B2; EP4118358A1; DE102020106335B3; DE102020008007A1; DE102019135760A1; CN114938664B; CN115485487A; WO2021180652A1; CN114938664A; CN113374810B; CN115992855A; US20210278872A1; US20230029016A1; DE102020106328B3; CN113374810A; WO2021123343A1

Abstract

A magnetorheological braking device (1) with a fixed holder (4) and with two braking components (2, 3), wherein one of the two braking components (2, 3) is connected fixedly to the holder (4) so as not to rotate relative thereto, and wherein the two braking components (2, 3) are continuously rotatable relative to one another, wherein a first braking component (2) extends in the axial direction (20), and wherein the second braking component (3) comprises a shell part (13) of hollow configuration which extends around the first braking component (2). A peripheral gap (5) which is filled with a magnetorheological medium (6) is configured between the first and the second braking component (2, 3). The first braking component (2) comprises an electric coil (26) and a core (21) which extends in the axial direction (20) and which is made from a magnetically conductive material, wherein the core (21) comprises a main body (33). Magnetic field concentrators (80, 81) which are configured on the core and/or magnetic field concentrators (80, 81) which are configured on the shell part protrude into the gap (5), which results in a peripheral gap (5) with a variable gap height (5b). The electric coil (26) is wound around at least one section of the core (21), with the result that a magnetic field (8) of the electric coil (26) runs through the core (21) and the magnetic field concentrators (80, 81) and through the gap (5) into a wall of the shell part (13).

Description

Magnetorheological braking device

The invention relates to a magnetorheological braking device with a stationary holder and with at least two braking components and / or damper components. The magnetorheological braking device according to the invention can be used in a wide variety of technical fields for braking relative movements to one another. The magnetorheological braking device according to the invention can also be used as a haptic operating device and, for example, when operating technical devices in vehicles (as a rotary actuator; rotary / push actuator; for infotainment, air conditioning, gear selector switch, navigation, seat adjustment, in the steering or in the steering wheel,

Chassis adjustment, driving mode adjustment ...) Motor vehicles, aviation and aircraft, ships, boats, agricultural engineering (tractors, combine harvesters, harvesting machines, other field machines for agriculture), construction machinery and machines for material handling (forklifts ...) or for medical or industrial systems are used. The invention can also be used in the operation or as an input device for washing machines, kitchen / household appliances and devices, radios,

Cameras and film cameras, hi-fi and television systems, smart devices, smart home devices, laptops, PCs, smartwatches, in a crown wheel of a wristwatch or as a computer mouse or as a rotary wheel in a computer mouse or controllers, game consoles, gaming equipment, a rotary knob in one Keyboard or other devices.

Magnetorheological fluids, for example, have very fine ferromagnetic particles such as carbonyl iron powder distributed in an oil. In magnetorheological fluids, spherical particles with a production-related Diameters from 1 to 10 mpi are used, the particle size and shape not being uniform. If such a magnetorheological fluid is exposed to a magnetic field, the carbonyl iron particles of the magnetorheological fluid are linked along the magnetic field lines, so that the rheological properties of the magnetorheological fluid (MRF) are significantly influenced depending on the shape and strength of the magnetic field.

With WO 2012/034697 A1 a magnetorheological transmission device has become known which has two components that can be coupled, the coupling intensity of which can be influenced. A channel with a magnetorheological medium is provided to influence the coupling intensity. The magnetorheological medium in the channel is influenced by a magnetic field. Rotary bodies are provided in the channel, on which acute-angled areas and areas containing the magnetorheological medium are provided. The channel or at least a part thereof can be acted upon by the magnetic field of a magnetic field generating device in order to selectively chain the particles and to wedge or release them with the rotating body. This magnetorheological transmission device can also be used on a rotary knob to operate technical devices. Such a magnetorheological transmission device works and allows the transmission of very high forces or moments with a relatively small structural shape at the same time.

WO 2012/034697 A1 also discloses a rotary knob or control knob in which the actual knob is attached so that it can rotate about a shaft. The braking torque can be controlled via the magnetic field of an electrical coil. If a higher braking torque that can be generated is desired, cylindrical rollers can also be used instead of spherical rotating bodies, so that the magnetic field acts over a longer distance or larger area. It has been shown, in particular in the case of rotary or control knobs with a relatively small diameter, that an extension of the rolling elements does not necessarily lead to an increase in the maximum Generable braking torque leads. It has been found that this is due to the fact that the magnetic field is closed or has to go through the central shaft. The small diameter of the shaft limits the braking torque that can be generated, as the magnetic field required for braking in the (shaft) material is quickly saturated. The material through which the magnetic field flows does not allow any higher magnetic flux, which is why no stronger magnetic field can reach the rollers. The smallest cross section in the overall magnetic circuit through which the magnetic field flows defines the maximum possible magnetic flux and thus the maximum braking torque in the braking device. The use of longer rollers as rotating bodies can then even have a disadvantageous effect on the braking torque that can be generated, since the magnetic field is distributed over the longer roller surface. There is a lower field strength. Because the achievable braking effect does not depend linearly on the magnetic field, but increases disproportionately with stronger magnetic fields, the achievable braking effect decreases accordingly with weaker magnetic fields.

It is therefore the object of the present invention to provide a magnetorheological braking device which, especially with small or even very small diameters, allows a high braking torque (torque) or a higher braking torque (torque) than in the prior art Case is.

This object is achieved by a magnetorheological braking device having the features of claim 1. Preferred developments of the invention are the subject matter of the subclaims. Further advantages and features of the magnetorheological braking device emerge from the general description and the description of the exemplary embodiments.

A magnetorheological braking device according to the invention has a stationary holder and at least two braking components. One of the two brake components is non-rotatably connected to the holder and the two brake components are relative to one another continuously rotatable. A first braking component extends in an axial direction. The second brake component comprises a casing part which can be rotated around the first brake component and is hollow. A circumferential gap which is at least partially and in particular completely filled with a magnetorheological medium is formed between the first and the second brake component. The magnetorheological medium wets the brake components. The first brake component comprises (at least) one electrical coil and a core made of a magnetically conductive material and extending in the axial direction. The core comprises a base body. Magnetic field concentrators formed on the core and / or magnetic field concentrators formed on the shell part protrude into the gap, so that a circumferential gap with a gap height that is variable (over the circumferential angle) results. The electrical coil is wound around at least one section of the core, so that a magnetic field of the electrical coil runs through the core and the magnetic field concentrators and through the (axially and / or radially extending) gap into a wall of the shell part.

The magnetic field concentrators preferably extend over at least one angular segment over the outer circumference of the core.

The first braking component defines an axial direction. The first brake component can, however, also be designed to be angled at least locally to the axial direction. The wording that the core of the first brake component extends in the axial direction is understood in the sense of the present invention to mean that the core also extends at least essentially in the axial direction. The core can have a course that has a slight angle to the axial direction. For example, the core can also be oriented at an angle of 2.5 ° or 5 ° or 10 ° or 15 ° to the axial direction. The winding of the electrical coil also does not have to be aligned exactly in the axial direction around the core be. The electrical coil can also be wound around the core at an angle of 5 ° or 10 ° or 15 ° or the like to the axial direction. In all cases, however, it is preferred that an angle between the alignment of the core and the axial direction and an angle between the winding of the electrical coil and the axial direction is less than 20 ° and in particular less than 10 °.

The magnetorheological braking device according to the invention has many advantages. A considerable advantage of the magnetorheological braking device according to the invention is that the electrical coil is provided on the first braking component. A particular advantage arises from the fact that the magnetic field concentrators are firmly connected to the core or the shell part and, in particular, are connected to it in one piece. This enables a particularly simple structure. It has surprisingly been found that the magnetic field concentrators do not have to be designed as self-rotating or rotatable rolling elements, but that fixed magnetic field concentrators also reliably and reproducibly provide a strong increase in the braking torque that can be generated. The magnetic field concentrators can either be manufactured separately and firmly connected to the core or the shell part and z. B. screwed, riveted, soldered, welded or possibly also glued or pressed. Amazingly, it is also possible to attach the magnetic field concentrators to the shell part. Overall, a high braking torque is generated with a small (and even smaller) installation space. As a result, the braking torque can be increased overall or kept the same with a smaller installation space. It also opens up new possibilities, since a larger braking torque can be generated with a considerably smaller installation space than before.

The magnetic field or the magnetic field lines preferably run transversely through the first or inner one Braking component. An extension of the first braking component then increases the possible magnetic flux and thus the braking torque with the same diameter. The core diameter, which is usually not constructively larger, then does not restrict the magnetic flux.

In the magnetorheological braking device, the magnetic field concentrators form transmission components. The magnetic field concentrators or the transmission components are at least partially and in particular essentially completely or completely surrounded by a magnetorheological medium. Overall, a magnetorheological fluid is preferably used as the magnetorheological medium.

A plurality of magnetic field concentrators (as transmission components) are preferably arranged distributed over the circumference of the gap. The magnetic field concentrators are not around themselves but rotate with the braking component to which they are attached. This results in a relative movement in the gap during rotation.

It is possible that, in addition to the magnetic field concentrators, other transmission components are also included which, for. B. are designed as rolling elements. In the context of the present invention, the term “rolling element” is to be understood as meaning a rotating element which is suitable for rolling in the gap on the first or second braking component.

In a preferred embodiment, the magnetorheological braking device comprises a stationary holder and at least two brake components, one of the two brake components being non-rotatably connected to the holder and the two brake components being continuously rotatable relative to one another, with a first brake component extending in the axial direction and with the The second brake component comprises a shell part which extends around the first brake component and is hollow and at least in sections cylindrical on the inside, wherein between the first and the second Brake component a circumferential and at least partially filled with a magnetorheological medium gap is formed.

The first brake component comprises at least one electrical coil and a core made of a magnetically conductive material extending in the axial direction, the core comprising a base body and outwardly protruding core contours as magnetic field concentrators, so that a circumferential gap (with over the circumferential angle) variable gap height results, and wherein the electrical coil is wound around at least a portion of the core, so that a magnetic field of the electrical coil through the core and through at least one outwardly protruding core contour formed thereon as a magnetic field concentrator and through which (axially or radially) to the outside subsequent gap runs into a wall of the shell part. In particular, the magnetic field concentrators extend over at least one angular segment over the outer circumference of the core.

In particular, each angular segment is smaller than 150 °.

Preferably, no magnetic field concentrator is arranged outside the angular segment (or the angular segments).

In particular, at least one angular range is provided concentrators without a magnetic field. An angular range without magnetic field concentrators is preferably provided between at least two angular segments. Preferably, at least two opposite angular areas are provided without magnetic field concentrators. In particular, an angular range (without magnetic field concentrators) is greater than 10 ° or 15 ° or 30 ° or preferably greater than 45 ° or greater than 60 ° and can reach 75 ° and exceed it by far. In a specific embodiment, an angular range has a size between 45 ° and 135 ° and preferably between 75 ° and 135 °.

The electrical coil wound around the core in the axial direction is preferably outside the angular segment (or the WinkelSegmente) added to the core. The electrical coil then particularly adjoins the surface. This means in particular that the electrical coil is received in the angular region or in the angular regions on the core.

Preferably, the angular segments and the angular ranges complement each other at least substantially or completely to form 360 °. Angular segments and angular regions are preferably arranged alternately over the circumference.

In a preferred development of the invention, at least one magnetic field concentrator has a cross-sectional area that tapers towards the distal end.

At least one magnetic field concentrator is preferably rounded at the distal end.

It is preferred that the core has a plurality of arms and / or the jacket part has a plurality of arms

Includes magnetic field concentrators that protrude radially and / or axially. Arms project radially outward and / or axially to the side from the core. Arms preferably protrude radially inwards and / or axially to the side from the casing part.

In all of the configurations it is preferred that at least one arm is surrounded by an electrical coil. Particularly preferably, a plurality of arms are each surrounded by an electrical coil.

Preferably, a radial length of a (radially protruding) arm is smaller than a length of the arm in the axial direction.

At least one electrical coil is preferably wound around the axis and essentially generates a magnetic field in the axial direction (radial coil).

In particularly preferred developments, at least one electrical coil is wound around the core in the axial direction and essentially generates a magnetic field in the radial direction (lying coil).

In particular, the magnetic field concentrators form a star-shaped outer contour (in cross section).

The casing part preferably has a cylindrical inner surface over at least one axial section.

A maximum (outer) diameter of the electrical coil in a radial direction within a or the coil plane is preferably greater than a minimum (outer) diameter of the core in a radial direction transverse and in particular almost perpendicular or also perpendicular to the coil plane. However, the minimum diameter does not have to be perpendicular to the plane of the coil.

Preferably the electrical coil extends axially around at least one arm. In particular, a radial gap height between an outer end of an arm and an inner surface of the casing part is smaller than a radial gap dimension between the outer surface of the first brake component next to the arm and the inner surface of the casing part. In addition to the arm, the surface of the base body can be formed. In addition to the arm, there can also be a surface of a potting compound when this is filled in, in order to e.g. B. to reduce the volume for the magnetorheological medium and in particular magnetorheological fluid (MRF).

The second brake component is preferably accommodated axially displaceably or displaceably on the first brake component in order to enable volume compensation in the event of temperature changes.

In particular, the second brake component is rotatably received on the first brake component via two bearing points of different outer diameters in order to effect a change in volume in a chamber formed between the first and the second brake component by means of an axial displacement. It is preferred that at least one shielding device is included for at least partial shielding of the sensor device from a magnetic field of the electrical coil or for shielding other magnetic fields.

The shielding device preferably comprises at least one shielding body surrounding the ring magnet unit at least in sections, the shielding device comprising at least one separating unit arranged between the shielding body and the ring magnet unit and / or at least one magnetic decoupling device arranged between the shielding body and the jacket part.

In particular, the separating unit and / or the decoupling device have a magnetic conductivity that is many times lower than that of the shielding body.

The shielding device can consist of several parts and, for. B. comprise at least one or two axial ring washers and at least one ring sleeve.

It is preferred that the shielding device and the magnetic ring unit are arranged at a distance from one another. A spacer can be arranged in between. In simple configurations, a plastic part such as an injection-molded part can be arranged between them and hold the parts at a defined distance from one another.

A closed (and externally sealed) chamber is preferably formed between the brake components. The second brake component is rotatably received at a first end of the closed chamber on the first brake component (at a first bearing point) and in particular is supported, the closed chamber being substantially or completely filled with the magnetorheological medium.

Preferably, the second brake component is axially displaceably received on the first brake component and in particular stored, so that a volume of the closed chamber changes by a relative axial displacement of the brake components in order to compensate for temperature-related volume changes.

It is advantageous if the electrical coil is wound around the core in the axial direction and essentially generates a magnetic field in the radial direction. Then there is the advantage that a stronger braking torque can be generated by extending a magnetic field concentrator in the axial direction. Simultaneously with the lengthening of the magnetic field concentrator, the electrical coil, which extends in the longitudinal direction of the first braking component, can also be lengthened (meaningfully). With an electrical coil that is made longer in the axial direction, a larger passage area (cross-sectional area through which the magnetic field flows) is made available for the magnetic field. Therefore, an increase in the length of the first braking component in the axial direction also increases the cross-section of the core. As a result, a stronger braking torque can be achieved by lengthening the first braking component in the axial direction.

In preferred embodiments, at least some of the magnetic field concentrators consist of a magnetically conductive material. It is also possible for some of the transmission components to consist of a magnetically non-conductive material. If magnetic field concentrators made of a magnetically conductive material are used and transmission components made of a magnetically non-conductive material are used at the same time, the magnetic field is concentrated in the area of the magnetically conductive magnetic field concentrators. This leads to the concentration of the magnetic field (increase of the magnetic field strength) and to a local amplification (magnetic field line concentration). For example, the increases magnetic field strength in the gap from values of less than 350 kA / m to values of up to 1,000 kA / m or more. The high (concentrated) field strength attracts more carbonyl iron particles from the magnetorheological fluid, and carbonyl iron accumulates (clusters). This in turn allows the generation of higher shear stresses and thus higher braking torques.

Since the relationship between the braking torque that can be generated and the strength of the magnetic field is not linear, and since the braking torque that can be generated becomes disproportionately stronger as the magnetic field becomes stronger, a considerable increase in the braking torque that can be generated can be achieved (with the same installation space / dimensions). It is also possible to select a correspondingly smaller number of magnetic field concentrators.

If, in the given installation space, higher braking torques than in the prior art and at the same time (very) low manufacturing costs are required, the axial width of the

Magnetic field concentrator are very small and designed as a continuous disc (closed contour). Out

For reasons of manufacturing costs, the star contour or similarly configured radially or axially protruding arms with interrupting spaces can be dispensed with. The specially selected (very) small width and special contour of the magnetic field concentrator also concentrates the magnetic field and, as described above, leads to high field strengths in the (ring) gap and thus to carbonyl particle concentration (cluster formation). Although the field strengths in the active gap are not as high as in the case of individual arms because of the larger transition area, they are sufficient for some applications, especially when there is high cost pressure.

In all configurations, it is not necessary to increase the brake torque that can be generated to increase the diameter of the first brake component. This is very important because there are many Possible uses do not allow a larger outer diameter of a braking device or a larger one

Outside diameter would be a serious competitive disadvantage (e.g. an oversized dial on the side of a wristwatch or a scroll wheel on a computer mouse or a thumb roller on a motor vehicle). In order to increase / increase the braking torque, the first braking component can be made axially longer, which is not a disadvantage or a minor disadvantage in terms of installation space.

In all of the configurations, it is preferred that the casing part is formed on a rotary knob or rotary wheel or includes one. The rotary part can preferably be formed in one piece with the rotary knob or rotary wheel. In such configurations, it is preferred that the rotary knob or the casing part is designed "pot" -shaped. The "cover" of the casing part can be connected in one piece to a rotary part designed as a sleeve part or fastened to it separately.

The casing part preferably consists of a magnetically conductive material or comprises a magnetically conductive sleeve part and provides an outer ring for the magnetic field. The magnetic field for generating a braking torque runs through the first braking component and passes through the gap at the magnetic field concentrators, which are designed to be magnetically conductive. The magnetic field enters the shell part from the magnetic field concentrators. There the magnetic field lines run back before the magnetic field lines re-enter the first braking component. There is thus a closed magnetic circuit or closed magnetic field lines.

Under the influence of a magnetic field, a wedge effect develops at the magnetic field concentrators when the first and second braking components rotate relative to one another, as is basically described in WO 2012/034697 A1.

The disclosure of this document is fully incorporated into this Registration recorded. The braking torque in the present invention is also generated by the wedge effect on the magnetic field concentrators, even if the magnetic field concentrators cannot rotate around themselves, but are attached to the first or second brake component.

Preferably, at least one radial wall thickness of the casing part or the sleeve part of the casing part is at least half as large as a gap width of the gap and / or a radial length of a magnetic field concentrator. A radial wall thickness (of the sleeve part) of the casing part is preferably greater than 3/4 of the gap width of the gap. The radial wall thickness (of the sleeve part) of the casing part can in particular also be greater than a radial length of a magnetic field concentrator. A sufficient wall thickness of the jacket part made of a magnetically conductive material or the sleeve part of the rotating part can ensure that the desired field strength of the magnetic field can be generated in the area of the rolling elements in order to be able to generate a high braking torque.

In all configurations, it is preferred that a length of the first braking component in the axial direction is greater than a length of a magnetic field concentrator in the axial direction. If the magnetic field concentrator is made shorter in the axial direction than the first braking component, this leads to a three-dimensional concentration of the magnetic field in the edge region of the magnetic field concentrator. The magnetic field can practically only pass through the gap in the sections in which there is a magnetic field concentrator.

A length of the gap in the axial direction is preferably at least twice as great as a length of a magnetic field concentrator in the axial direction. It is also possible and preferred that two or more

Magnetic field concentrators are arranged one behind the other in the axial direction. The first brake component is preferably of essentially cylindrical design and comprises a cylindrical base body as the core and the electrical coil or the electrical coils. It is also possible that, for example, a ball for mounting a rotary knob is included, which can be arranged centrally at the distal end in order to provide a simple mounting between the first brake component and the second brake component.

When using a "horizontal coil", the electrical coil can be wound in axial grooves and transverse grooves of the cylindrical base body (the first braking component). When using a "radial coil", the electrical coil can be wound in a circumferential groove. The respective grooves are preferably at least partially filled with potting compound. This prevents magnetorheological medium or magnetorheological fluid from entering the area of the coil wires. This could lead to a segregation of the fluid.

The holder preferably has a cable bushing. Connection cables for the coil and / or sensor cables and the like can be passed through the holder or through the cable bushing of the holder. This enables easy assembly and inexpensive manufacture.

The holder preferably has a receptacle for a rotationally fixed connection to the first brake component. The holder can hold the first brake component in a force-locking and / or form-locking manner. During operation, the braking torque between the first braking component and the second braking component is dissipated via the holder.

The holder preferably has a cylindrical running surface for a bearing and supports the casing part rotatably on the holder.

A seal for sealing the gap is preferably arranged on the cylindrical running surface, the seal in particular is arranged closer to the gap than the bearing. This reliably protects the bearing from the magnetorheological medium. Such a configuration enables a compact structure and reliable operation. The camp can e.g. B. be a plain or roller bearing.

The cylindrical running surface is preferably hardened and / or has a higher surface quality than the radially outer surface of the receptacle. This can reduce manufacturing costs.

In advantageous refinements, the cylindrical running surface has an outer diameter which is at least 3 mm smaller than an outer diameter of the receptacle of the holder.

The holder is preferably attached to a console or another component.

In preferred developments, a device component comprises at least one magnetorheological braking device, as described above. Such a device component can comprise at least one user interface, a control panel, a display, a touch-sensitive display with or without haptic feedback and / or at least one sensor.

Use in a haptic operating device that comprises at least one magnetorheological braking device is also possible. A user interface, a control panel, a display, a touch-sensitive display with or without haptic feedback and / or at least one sensor is preferably also included. In addition to operation, such a configuration also enables information to be displayed or output at the same time during operation. This enables, for example, an operating button with a simultaneous output display.

In all of the configurations, it is possible for a pressure-sensitive sensor to be attached to the holder or to attach a sensor to the holder such a sensor is assigned. For example, a pressure-sensitive sensor can be attached in the holder. However, it is also possible for a piezo sensor to be attached to the lower part, etc. The holder can also be designed in two parts and register an axial displacement of the two parts with respect to one another. Haptic feedback can be provided.

In all configurations, it is preferred that a difference between a clear inside diameter (of the sleeve part) of the casing part and an outside diameter of the first brake component is greater than 3 mm and less than 90 mm. It is also preferred that an outer diameter of the (sleeve part) jacket part is between 5 mm or 10 mm and 120 mm. The height of the casing part is preferably between 5 mm and 120 mm. In all of the configurations, it is preferred that a control device is included, which is designed to produce a variable braking effect with the electrical coil.

Overall, the present invention works particularly preferably according to the basic principle of wedge clamping, with a magnetic field concentrator grazing past the walls at a certain distance. The wedge effect is created by a magnetic field, so that a high braking torque can be generated.

By using a "lying coil", better scalability can also be achieved. This makes it possible to generate a scalable and larger braking torque using longer magnetic field concentrators and an axially longer electrical coil. The diameter of the first braking component does not have to be selected larger, to pass through a corresponding magnetic field, because with an axial lengthening of the core, the area of the core (cross-sectional area) also increases. If necessary, the axial length can also be reduced considerably if only a relatively low braking torque is required. The installation space can be adapted accordingly. Another advantage is that the electrical connection cable for the electrical coil can easily be led out even for large series. A tightness of the agnetorheological braking device and scaling can be made possible by simple means.

In principle, a larger moment can be generated by the magnetorheological braking device via longer magnetic field concentrators, since the effective length increases. At the same time, the larger core area ensures that the

Magnetic field concentrators are always exposed to a corresponding magnetic flux density. The magnetic field strength of the "wedge" on the magnetic field concentrators can be selected to be higher than in the prior art. Long magnetic field concentrators or several axially offset magnetic field concentrators can be used to which a sufficiently strong magnetic field can be fed.

In particular, when a "radial coil" is used, the magnetic field generated by the electrical coil goes radially through the core, then through the magnetic field concentrators and closes over the (sleeve part or) the jacket part or the outer cylinder. The magnetic field lines close once in one and, for example, the lower or left and once in the other and, for example, the upper or right half of the shell part. In simple configurations, the magnetic flux thus runs essentially two-dimensionally, regardless of how long or high the

Magnetic field concentrators are formed. Any scaling in length can thereby be achieved, since the magnetic field transmission area grows with it. In the case of electrical coils ("radial coils") wound concentrically around the longitudinal direction of the first braking component, however, the cross-sectional area in the core remains the same and can form a needle eye for the magnetic field as long as the diameter is not changed. A larger diameter of the first brake component also changes the space requirement, the installation dimensions and the weight of the magnetorheological braking device. It is advantageous that the fixed magnetic field concentrators now used do not change the speed of the rolling elements, which can be disadvantageous.

If longer magnetic field concentrators are used, the braking effect of one magnetic field concentrator that extends long in the axial direction can be better than that of two short ones that have the same overall length. This is due, among other things, to the fact that the liquid has to be displaced longer, since the edge is further away (hydrodynamic pressure).

In preferred embodiments, the magnetorheological braking device has a diameter (of the sleeve part) of the jacket part of between approximately 5 and 80 mm (+/- 20%), in preferred embodiments approximately 10 to 40 mm.

Overall, the invention provides an advantageous magneto-rheological braking device ("MRF brake"). The outer diameter of the MRF brake is usually specified, especially in haptic applications. There are ergonomic guidelines here so that the outside diameter is also larger (button or thumbwheel or mouse wheel outside diameter; area for the fingers). In addition, the larger the outside diameter, more locking torque is required, because the torque distance therefore increased (the finger force, i.e. the (tangential) force between the actuating finger (s) and the braking element or the outer surface of the braking element must or should remain the same, since on the one hand only a certain force can be applied by the user and the necessary forces on the fingers (fingertips) for the well-being during actuation (operating quality ) are important).

The electrical coil (electrical coil) can extend axially in preferred configurations. The magnetic field generated by the coil then goes radially through the core, then through the Magnetic field concentrators and closes over the outer cylinder (each by the opposite halves). This always remains the same, no matter how high (or long) the rolling element or MRF brake is.

The invention achieves the goal of obtaining an MRF brake that is as simple as possible, but nevertheless easily scalable, with a high braking torque and a compact outer diameter.

Instead of a (cylindrical) coil wire, a flat material made of copper or another suitable material can also be used.

The core, the magnetic field concentrators and the outer cylinder can be made of a simple steel (e.g. S235), without great demands on the surface quality and hardness, which preferably has good magnetic properties.

The core together with the electrical coil and potting compound are preferably centered and fixed in a "holder" (force-fit or form-fit connection) and the counter torque is transferred to a console or base plate or mounting plate or a housing. The holder preferably has a bore through which the A sealing element (e.g. O-ring) preferably seals the cable against the holder or the interior so that no liquid can escape from the interior via the cable a temperature sensor cable or other sensor cable can be fed through this opening.

The holder can also be made of a different material such as the core, roller body or outer cylinder. The reduction in diameter of the holder on the running surface has the advantage that the friction radius for the sealing element is smaller, which reduces the overall friction. In addition, because of the increased overall height as a result, a bearing element can be used which has the same bearing outer diameter as the inner diameter of the shell part. This reduces the manufacturing costs of the shell part, there is no production-related paragraph (turning) required. The preferred roll body height is between 3 and 6 mm, but can also be 1 or 2 mm. In this area it is difficult to obtain good bearings or sealing elements if the inside diameter of the holder does not create additional overall height.

A decorative or other element can be attached over the outer cylinder or the shell part, e.g. B. a rubberized button.

Viewed axially above, there is preferably a sphere or a spherical, spherical or spherical component (can also be a hemisphere) between the outer cylinder and the casting compound. This guides the two parts relative to each other. The ball is preferably fixed in the potting compound and the inner axial end face of the outer cylinder rotates relative to it. This creates a simple, low-friction and inexpensive storage (bearing point). A cone shape or the like is also possible. Instead of this type of mounting, any other type of mounting can be selected (e.g. sliding or roller mounting).

At least one component through which the magnetic field flows preferably consists at least partially or completely of the material FeSi3P.

In principle, a star contour cannot be applied to the core, but also from the inside into the surrounding jacket part or sleeve part. Such a construction can bring advantages in the coil design. You also gain space. In this case, too, different coil variants can be selected. An axial coil or "lying coil" is possible. A coil that is wound around the axis of rotation is also possible. Preferably, there is no longer any core material radially outside the electrical coil, since otherwise the magnetic field about it could be closed, whereby magnetic losses can arise. It is also conceivable to use more than one "lying coil", depending on how it is positioned. A radial coil would also be conceivable, since in this way the field is closed over all "teeth" or magnetic field concentrators at the same time.

In preferred developments of all configurations, the maximum torque that can be generated (field strength curve in the active gap; wedge effect) and / or the reaction time (the time until the moment is applied in the event of sudden current supply or current jumps = step response) depends on the selected inlet angle for the arms or the respective distal ones Ends of the magnetic field concentrators. The angle and the surface length generated by the outer design of the radial end of the arms and the mating surface influence the maximum torque that can be generated and the reaction time when a magnetic field or the field strength is built up in the active gap. Flatter (smaller) inlet angles and / or longer surfaces increase the torque that can be achieved. Larger (steeper) inlet angles and / or shorter surfaces shorten the response time.

Further advantages and features of the present invention emerge from the exemplary embodiments, which are explained below with reference to the accompanying figures.

In the figures show:

Figure la-lf schematic three-dimensional views of

Device components with a magnetorheological braking device;

FIG. 2 shows a cross section of a further device component with a magnetorheological braking device;

FIGS. 3a-3b show schematic cross sections of the magnetorheological braking device according to FIG. 2;

Figure 4 shows another cross section of a magnetorheological braking device;

FIG. 5 shows further schematic cross sections of a magnetorheological braking device in section;

FIG. 6 shows a schematic cross section of a magnetorheological braking device;

FIGS. 7a-7e show a further device component; and

Figures 8a-8c possible torque curves over the angle of rotation of a magnetorheological braking device of a device component according to the invention.

Figures la to lf show several device components 200 according to the invention in which the magnetorheological braking device 1 can be used. The device components 200 are each designed as a haptic operating device 100.

FIG. 1 a shows a haptic control button 101. The control button is attached via the console 50. The control button 101 is operated via the jacket part 13 or sleeve part 13e. The user interface 43 can also be used to transmit information.

In FIG. 1b, the device component 200 is shown as a thumb roller 102 with a haptic operating device 100. The thumb roller 102 can preferably be used in steering wheels, for example. However, the thumb roller is not limited to this application. The thumb roller 102 can generally also be usable with any other finger, depending on the installation situation.

In FIGS. 1c and 1d, the device component 200 according to the invention is designed as a computer mouse 103. The haptic operating device 100 is accommodated in the mouse wheel 106. The magnetorheological braking device 1 can be used to control a haptic feedback.

Figure le shows a joystick 104 as a haptic operating device 100, in which an agnetorheological braking device 1 is housed. In addition, the magnetorheological braking device 100 according to the invention can also preferably be used in a gamepad 105 in order to give the player haptic feedback as a function of the game situation, see FIG.

In these exemplary embodiments, the magnetorheological braking device 1 has a casing part 13 or rotating part 13 or sleeve part 13e, which is rotatably received. The torque required to rotate the casing part 13 or rotating part 13 is adjustable.

A user interface 43 can be arranged on the upper side of the magnetorheological braking device 1. Such a user interface 43 can be designed, for example, as a display device or also as a touch-sensitive input option (touchpad, movement and gesture control, image recognition ...).

A haptic operating device 100 can be used, for example, to operate machines, medical devices or for use in and for the motor vehicle. Use on other devices or other devices is also possible.

FIG. 2 shows a device component 200 according to the invention in section with a magnetorheological braking device 1 according to the invention. The transverse grooves 32 in which the electrical coil 26 of the magnetic field generating device 113 is wound at the axial ends of the core 21 can be seen. The electrical coil 26 is wound around the axis 12 in the axial direction and essentially generates a magnetic field in the radial direction. In the axial direction, sealing compound 28 is provided at each end at both ends. In the area of the cable bushing 35, a separate seal 38 is provided over, for example, the drawn O-ring or the like.

A length or height 13c of the magnetic field concentrator 80, 81 and the jacket part 13 or the sleeve part 13e or the second Braking component 3 in the axial direction 20 is preferably between 1 mm and 100 mm or between 5 mm and 90 mm. A coating 49 can be applied to the outside of the second brake component 3, so that the external appearance of the rotary knob 23 is essentially determined by the surface of the coating 49.

The material of the sleeve part 13e or of the jacket part 13 as a whole is magnetically conductive and serves to close the magnetic circuit. A wall thickness 13d between the outer diameter 13b and the inner diameter 13a of the sleeve part 13e is preferably at least half as large as a radial extension of the magnetic field concentrators 80.

The diameter 36a of the receptacle 36 is preferably considerably larger than the diameter 37a of the cylindrical running surface 37. This reduces the friction on the seal 38. In addition, standardized bearings can be used.

It is also possible to make the core 21 and also the holder 4 in two parts. The separation preferably runs along the center line drawn in FIG. 2, which results in a left and right (core) half. The two core halves can be separated from one another by a magnetically non-conductive element (e.g. seal). The casting compound volume 28 is then preferably part of the core half (s), which results in a semicircular element with a circumferential groove on the separating surface for the electrical coil 26. Furthermore, the receptacle 36 is preferably also separated into two halves. A receiving half can also form a part with a core half (be made in one piece) or a core half can be made in one piece with a complete receiving unit 36.

Here, the haptic operating device 100 with the magnetorheological braking device 1 is mounted on one side. The second brake component 3 is received here only at the first end 111 of the closed chamber 110 at an end section 121 of the first brake component 2, ie the second brake component 3 is only stored at the first bearing point 112 by the bearing 30. When the volume 114 within the closed chamber 110 changes, the second brake component 3 can move slightly to and fro. It is assumed here again that the first brake component 2 is stationary. In this case, part of the diameter 116 of the first brake component 2 extends or retracts at the first bearing point 112. The volume 114 of the closed chamber 110 changes. Advantageously, the system is practically always at ambient pressure within the given range of motion. An additional load on the seal 38 is prevented.

FIGS. 3a and 3b show various schematic cross sections of the magnetorheological braking device 1, which can be used in the device components 200 according to FIG. 2 and also in other exemplary embodiments.

The inner brake component 2 is designed to be stationary and is surrounded by the continuously rotatable brake component 3. The second brake component 3 has a casing part 13 which can rotate around the first brake component 2 and is hollow and cylindrical on the inside. The gap 5 running around between the first and second brake components 2, 3 can be seen. The gap 5 is here at least partially and in particular completely filled with a magnetorheological medium 6.

The first brake component 2 has the core 21, which extends in the axial direction 20, and is made of a magnetically conductive material, and an electrical coil 26 which is wound around the core 21 in the axial direction 20 and spans a coil plane 26c. The magnetic field 8 of the electrical coil 26 extends transversely to the axial direction 20 through the first braking component 2 or the core 21.

It can be clearly seen that a maximum external diameter 26a of the electrical coil 26 in a radial direction 26d within the coil plane 26c is greater than a minimum outer diameter 21b of the core 21 in a radial direction 25 across and z. B. perpendicular to the coil plane 26c.

The magnetic field concentrators 80 protrude radially outward from the base body of the core 21. The course of the magnetic field 8 is shown by way of example in FIG. 3a.

The electrical coil is arranged outside of the angle segments 61 and 62. There are no magnetic field concentrators 80 outside of the angular segments 61 and 62. An angular region 63, 64 without magnetic field concentrators 80 is arranged between the angular segments 61 and 62. Here, the turns of the electrical coil 26 run in the opposite angular regions 63, 64.

The cores 21 have outwardly protruding arms 83 as magnetic field concentrators 80 which extend radially outward from the base body 33. In FIGS. 3a and 3b, the chamber 110 between the core 21 and the jacket part 13 is completely filled with MRF.

The maximum outer diameter 26a of the coil 26 is larger than the minimum core diameter 21b. The radial extension of the gap 5 varies over the circumference. At the outer ends of the magnetic field concentrators 80 there is only a small radial gap height 85, while a radial gap dimension 87 between the braking component 2 and the braking component 3 is considerably larger at other points.

The radial gap height 85 between an outer end of an arm 83 and an inner surface 67 of the casing part 13 is, however, considerably smaller than a radial gap 87 between the outer surface 86 (ie the core 21 directly or a surface of a potting compound 28 on the core) of the first brake component 2 next to the arm 83 and the inner surface 67 of the shell part 13.

Figure 3b shows a variant of Figure 3a, in which to Reduction of the MRF volume, the chamber 100 is filled with potting compound 28 via a cylindrical section. This reduces the required volume 114 of MRF. The radial gap dimension 87 is significantly reduced, but remains considerably (at least a factor of 2 or 3 or 5 or 10) greater than the radial gap height 85. This ensures that the wedge effect described occurs. The MRF particles 19 are linked in the acute-angled areas 10 and form a type of wedge, which leads to a considerable braking torque. In FIGS. 3 a and 3 b, the magnetic field concentrators 80 form a type of radial arms 83.

FIG. 4 shows two schematic cross sections of other embodiments in which the magnetic field concentrators 80 are formed by individual, outwardly protruding radial arms 83, the radial arms 83 being formed in one piece with the core 21 and made of a material with good magnetic conductivity.

Here, each individual arm 83 is wrapped around by an electrical coil 26 of the magnetic field generating device 113. The electrical coils 26 are preferably controlled jointly. The distal and here radially outer ends 82 of the arms 83 can be wedge-shaped, rounded or also angular. With radially inwardly projecting arms 83 as

Magnetic field concentrators 81 can accordingly have the radially inner end as a distal end 82 wedge-shaped, rounded or also angular. The shape influences the maximum torque that can be generated and the reaction time.

The arm height or radial length of the arm 84 is considerably greater (a factor of 10, 50, 100 and far more) than the radial gap height 85 between a distal end of an arm 82 and an inner surface 67 of the casing part 13.

The radial gap height 85 between an outer end or distal end 82 of an arm 83 and an inner surface 67 of the Shell part 13 is considerably smaller than a radial gap 87 between the outer surface 86 (core 21 or surface of a potting compound 28) of the first brake component 2 next to the arm 83 and the inner surface 67 of the shell part 13. The ratio is preferably greater than 2, 5 or 10 or more. Some magnification is important for wedge formation.

In Figure 5, three different outer contours of a core 21 are shown on a shell part 13 formed with a cylindrical cavity. The radially outwardly protruding

Magnetic field concentrators 80 can be shaped differently. The outwardly protruding magnetic field concentrators 80 form a gap 5 that is variable over the circumference, so that the magnetic field 8 is bundled in the area of the magnetic field concentrators 80 when it passes from the core 21 into the jacket part 13.

In the left illustration of FIG. 5, a dashed variant is shown purely schematically, in which the magnetic field concentrators 81 protrude inward and the core 21 is provided on the inside. Then an inverted picture emerges. By shaping the distal ends 82 of the magnetic field concentrators 80 and 81, different properties can be achieved. In this way, the focus can be placed on a higher braking torque or a fast response time.

FIG. 6 shows a schematic variant with a central cylindrical core 21 and a jacket part 13 from which magnetic field concentrators 81 protrude periodically radially inward. A highly schematic magnetic field line 8 is shown, which radially passes through the gap 5 between the core 21 and a magnetic field concentrator 81. At the narrow point, a heap of the particles 19 of the MRF is linked and forms a wedge in an acute-angled area 10, which generates a high braking torque.

In addition to the variant shown, in which the electrical coil 26 is wound around the core 21 in the axial direction, is also a variant is possible in which the electrical coil 26 is wound radially around the axis of rotation 2.

FIGS. 7a to 7e show a further embodiment of a device component 200 which has a magnetorheological braking device 1 and comprises braking components 2 and 3. A "lying or axial coil" is again used, in which the electrical coil 26 is wound around the core 21 in the axial direction 20 and again has a maximum radial coil diameter 26a which is greater than a minimum core diameter 21b of the core 21. Also Here, magnetic field concentrators 80 projecting radially outward are provided, which concentrate the magnetic field in the thin radial gap and ensure the wedge effect. This is not a conventional shear damping, because the gap height of the gap 5 changes massively over the circumference. Here are horizontal Lines are drawn in which show the radial starting point for the magnetic field concentrators 80. Outside the magnetic field concentrators 80, the gap height is very much greater (here a factor of> 50 or 100 or 1000).

Here, the device component 200 is designed as a haptic operating device 100 and, in detail, as an operating button 101. The second brake component 3 is received at the first end 111 of the closed chamber 110 at the bearing point 112. In addition, the second brake component 3 is received at the second bearing point 118 at the second end 115 of the closed chamber 110 on the first brake component 2. As a result of the mounting, forces are absorbed in the (global) radial direction 122, while the brake components 2, 3 can still be displaced axially relative to one another.

Here, the bearing is realized by means of a stub axle 119 with the diameter 117 at the second bearing point 118. The sealing ring 46 prevents the magnetorheological medium 6 from flowing into the area behind the stub axle 119.

The diameter 117 at the second bearing point 118 is here It is made significantly smaller than the diameter 116 at the first bearing point 112. A change in volume is also made possible here in the event of an axial displacement. Volume changes caused by temperature and changes in volume caused by leaks can be compensated. For this purpose, there is a relative axial displacement of the first brake component 2 to the second brake component 3. In order to reduce the throttling effect via the gap 5 in the event of an axial displacement, a compensation channel 120 can be provided which connects the two areas near the bearing points 112, 118 with one another.

In addition, a sensor device 70 for detecting an angular position of the haptic operating device 100 is also present here. The magnetic field sensor 72 is integrated in the stationary receptacle 4 or the first brake component 2. The cable 45 of the magnetic field sensor 72, i. H. the sensor line 73 passed through the cable bushing 35 to the outside.

The first axle part or the holder 4 of the brake component 2 can, as shown in FIGS. 7b and 7c, preferably be designed in two parts. This primarily simplifies the assembly of the electrical lines and, in particular, of the sensor line 73 within the first brake component 2. The cables can be laid through the open cable bushing 35.

In Figure 7d, the sensor device 70 is shown again in detail. The first brake component 2 and the second brake component 3, designed here as a rotating part, are only indicated (dashed lines). The sensor device 70 is supported by the decoupling device 78 on the rotatable second brake component 3 in a magnetically decoupled manner. The

Shielding device 75 here consists of three shielding bodies 76, which reduce the scattering of the magnetic field 8 of the electrical coil 26. In addition, there is also a separating unit 77 for magnetic separation. The magnetic ring unit 71 is used to measure the orientation or the angle of rotation magnetorheological braking device 1 used. The magnetic field sensor 72 is arranged within the first brake component 2. Small relative axial displacements can also be used to detect a depression of an operating button 101, for example, see FIG. 7e.

An axial displacement changes the received signal 68 of the sensor device as shown in FIG. 8. FIG. 8 shows the course of the amplitude 69 of the signal 68 detected by the magnetic field sensor 72 as a function of the axial displacement of the brake components 2, 3 (horizontal axis). An axial displacement of the magnetic field sensor 72 with respect to the magnetic ring unit 71 changes the amplitude 69 of the detected signal 68. B. a mouse wheel 106 or other components can be detected.

The angle of rotation can also be detected with the same sensor or magnetic field sensor 72, the direction of the magnetic field 8 being determined in order to detect the angle of rotation. The intensity determines the axial position. A change in the signal 68 can therefore be used to infer that the pushbutton 74 has been actuated. This is advantageous because a single (multi-dimensional) Hall sensor can be used to determine the angular position and to determine an axial position.

FIGS. 8a, 8b and 8c show possible design variants for controlling a dynamically generated magnetic field 8 or a dynamically generated braking torque as a function of the angle of rotation.

FIG. 8a shows a variant in which a rotary knob is used as a haptic operating aid. The rotation resistance is shown over the rotation angle. With the controller 27, a left end stop 228 and a right end stop 229 can be generated. If you continue to turn the rotary knob 23 there is a high Magnetic field 8 or stop torque 238 is generated, as a result of which the rotary knob 23 opposes a high resistance to a rotary movement. The user receives the haptic feedback from an end stop 228, 229.

The rotary movement can be rasterized or generated. For example, this can be used to navigate through a graphical menu and select menu items. Here, directly next to the left end stop 228, a first grid point 226 is provided. B. corresponds to a first menu item. If the next menu item is to be selected, the rotary knob 100 must be turned clockwise. For this purpose, the dynamically generated higher magnetic field 8 or detent torque 239 or its frictional torque must be overcome before the next grid point 226 is reached. In FIG. 8a, a constant magnetic field 8 is generated for a certain angular range at the grid points 226 and at the areas in between, which is considerably lower at the grid points than in the areas in between and again significantly less than at the stops 228, 229.

An angular distance 237 between individual grid points can be changed dynamically and is adapted to the number of available grid points 226 or menu items.

FIG. 8b shows a variant in which the magnetic field does not rise suddenly towards the end stops 228, 229, but rather takes a steep course. Furthermore, ramp-like gradients of the magnetic field are provided at the grid points 226 on both sides of the rotation, whereby the resistance to rotation increases in the corresponding directions of rotation. Here, with the same operating device 100, only three grid points 226 are made available, the angular spacing 237 of which is greater than in the example according to FIG. 8a.

FIG. 8c shows a variant in which there is less resistance to rotation between individual grid points 226 and only an increased magnetic field 239 is generated directly adjacent to the raster points 226 in order to enable the individual raster points 226 to snap into place and, at the same time, to provide only a low rotational resistance between individual raster points 226. The basic moment 240 acts in between.

In principle, a mixture of the modes of operation and the magnetic field curves of FIGS. 8a, 8b and 8c is also possible. For example, in different submenus, a correspondingly different setting of the course of the magnetic field can take place.

It is also possible in all cases that with z. B. a ripple (grid) is not switched between little and more current with the same polarity as before (e.g. +0.2 to + 0.8A = ripple), but alternately with changed polarity, d. H. from +0.2 to + 0.8A and then the next ripple with -0.2A to - 0.8A and then the next moment peak from +0.2 to + 0.8A etc.

In all cases it is also possible for the operating modes of FIGS. 8a, 8b and 8c or a mixture of the operating modes to be selected using voice commands. The user selects a function (volume, station selection ...) by voice input (with local or remote voice recognition, e.g. via Alexa, Amazon Echo, Siri, Google voice input ...). The magnetorheological braking device 1 then provides a corresponding operating mode (volume = grid with increasing braking torque for increasing volume; radio station selection = grid with different increments, in between low braking torque until the transmitter is found).

The preferably low-alloy steel can retain a residual magnetic field. The steel is preferably demagnetized regularly or if necessary (e.g. by a special alternating field).

The material FeSi3P (silicon steel or silicon steel) or a similar material is preferably used for the components through which the magnetic field 8 flows. In all cases, voice or sound control can be carried out. With the voice control, the braking device 1 can be controlled adaptively.

If the rotating unit is not rotated, ie the angle is constant, the current is preferably continuously reduced over time. The current can also be varied as a function of the speed (angular speed of rotation of the rotary unit).

List of reference symbols:

1 magnetorheological 37a outer diameter braking device 38 seal

2 Brake component 43 User interface

3 brake component 45 cables

4 holder, seat 46 sealing ring

5 gap, channel 49 coating 5b gap height 50 console

6 Medium 61 angle segment

8 field, magnetic field 62 angular segment 10 acute-angled area 63 angular area

12 axis 64 angular range

13 shell part, rotating part 67 inner surface of 13 inner diameter 68 signal

13b outer diameter 13c height 69 amplitude 13d wall thickness 70 sensor device 13e sleeve part 71 magnetic ring unit

19 magnetic particles 72 magnetic field sensor

20 axial direction 73 sensor cable

21 Kern 74 buttons

21b minimum diameter 75 shielding device

23 Rotary knob 76 Shielding body

24 outer ring 77 separation unit

25 radial direction 78 decoupling device

26 coil 80 magnetic field concentrator

26a maximum diameter 81 magnetic field concentrator

26c coil plane 82 distal end

26d radial direction to 26c 83 arm

27 control device 84 radial length of the arm

28 casting compound 85 gap height 30 bearing 86 outer surface

32 transverse groove 87 gap dimension

33 (cylindrical) 100 haptic basic body control device

35 Cable entry 101 control head

36 Pickup 102 Thumb roller

36a outside diameter 103 computer mouse

37 cylindrical running surface 104 joystick Gamepad 118 second bearing point mouse wheel 119 stub axle closed chamber 120 compensation channel first end of 110 121 end section of 2 first bearing point 122 radial direction (global) magnetic field generation 200 device component device 226 grid point volume of 110 228 end stop second end of 229 end stop closed chamber 237 angular distance diameter first 238 Stop torque bearing point 239 grid moment diameter second 240 basic moment bearing point

Claims

Expectations :

1. Magnetorheological braking device (1) with a stationary holder (4) and with at least two brake components (2, 3), one of the two brake components (2, 3) being non-rotatably connected to the holder (4) and the two brake components ( 2, 3) are continuously rotatable relative to one another, with a first brake component (2) extending in the axial direction (20) and with the second brake component (3) having a hollow shell part (13) extending around the first brake component (2). comprises, wherein a circumferential gap (5) which is at least partially filled with a magnetorheological medium (6) is formed between the first and the second brake component (2, 3), characterized in that the first brake component (2) has at least one electrical coil (26) and a core (21) made of a magnetically conductive material and extending in the axial direction (20), the core (21) comprising a base body (33), and that at de m core trained

Magnetic field concentrators (80, 81) and / or magnetic field concentrators (80, 81) formed on the casing part (13) protrude into the gap (5) so that a circumferential gap (5) with a variable gap height (5b) results, and that the electrical Coil (26) is wound around at least a portion of the core (21) so that a magnetic field (8) of the electrical coil (26) through the core (21) and the magnetic field concentrators (80, 81) and through the gap (5) in a wall of the shell part (13) extends into it.

2. Magnetorheological braking device (1) according to claim 1, wherein the magnetic field concentrators (80, 81) extend over at least one angular segment (61, 62) over the outer circumference of the core (21).

3. Magnetorheological braking device (1) after preceding claim, wherein each angular segment (61, 62) is less than 150 °.

4. Magnetorheological braking device (1) according to one of the two preceding claims, wherein no magnetic field concentrator (80) is arranged outside the angular segment (61, 62).

5. Magnetorheological braking device (1) according to one of the three preceding claims, wherein the electrical coil (26) wound around the core (21) in the axial direction (20) is received outside the angular segment (61, 62) on the core (21) .

6. Magnetorheological braking device (1) according to one of the preceding claims, wherein at least one magnetic field concentrator (80, 81) has a cross-sectional area tapering towards a distal end (82).

7. Magnetorheological braking device (1) according to one of the preceding claims, wherein at least one magnetic field concentrator (80, 81) is rounded at the distal end (82).

8. Magnetorheological braking device (1) according to one of the preceding claims, wherein the core (21) comprises a plurality of arms (83) and / or the casing part (13) comprises a plurality of arms (83) as magnetic field concentrators (80, 81), which protrude radially.

9. Magnetorheological braking device (1) according to the preceding claim, wherein at least one arm (83) is surrounded by an electrical coil (26).

10. Magnetorheological braking device (1) according to the preceding claim, wherein a plurality of arms (83) are each surrounded by an electrical coil (26).

11. Magnetorheological braking device (1) according to one of the preceding claims, wherein a radial length (84) of a Arm (83) is smaller than a length of the arm (83) in the axial direction (20).

12. Magnetorheological braking device (1) according to one of the preceding claims, wherein at least one electrical coil (26) is wound around the axis (12) and essentially generates a magnetic field in the axial direction (20).

13. Magnetorheological braking device (1) according to one of the preceding claims, wherein at least one electrical coil (26) is wound in the axial direction (20) around the core (21) and essentially generates a magnetic field (8) in the radial direction (26d) .

14. Magnetorheological braking device (1) according to one of the preceding claims, wherein the magnetic field concentrators (80, 81) form a star-shaped outer contour.

15. Magnetorheological braking device (1) according to one of the preceding claims, wherein the jacket part (13) has a cylindrical inner surface (67) over at least one axial section.

16. Magnetorheological braking device (1) according to one of the preceding claims, wherein a maximum diameter (26a) of the electrical coil (26) in a radial direction (26d) within a / the coil plane (26c) is greater than a minimum diameter (21b) of the core (21) in a radial direction (25) transverse to the coil plane (26c).

17. Magnetorheological braking device (1) according to one of the preceding claims, wherein the electrical coil (26) extends axially around at least one arm (83) and wherein a radial gap height (85) between an outer end of an arm (83) and an inner surface (67) of the casing part (13) is less than a radial gap (87) between the outer surface (86) of the first brake component (2) next to the arm (83) and the inner surface (67) of the Shell part (13).

18. Magnetorheological braking device (1) according to one of the preceding claims, wherein the second braking component (3) is axially displaceably received on the first braking component (2) in order to enable volume compensation in the event of temperature changes and / or in the event of leakage.

19. Magnetorheological braking device (1) according to one of the preceding claims, wherein the second braking component (3) via two bearing points (112, 118) of different

Outer diameter (116, 117) is rotatably received on the first brake component (2) in order to effect a change in volume in a chamber (110) formed between the first brake component (2) and the second brake component (3) by an axial displacement.

20. Magnetorheological braking device (1) according to one of the two preceding claims, comprising a shielding device (75) for at least partial shielding of the sensor device (70) from a magnetic field of the electrical coil (26).

21. Magnetorheological braking device (1) according to the preceding claim, wherein the shielding device (75) comprises at least one shielding body (76) surrounding the magnetic ring unit (71) at least in sections, the shielding device (75) at least one between the shielding body (76) and the Magnet ring unit (71) arranged separating unit (77) and / or at least one magnetic decoupling device (78) arranged between the shielding body (76) and the rotating part (13).

22. Magnetorheological braking device (1) according to the preceding claim, wherein the separating unit (77) and / or the decoupling device (78) have a magnetic conductivity that is many times lower than that of the shielding body (76).

23. Magnetorheological braking device (1) according to the preceding claim, wherein the shielding device (78) comprises at least one axial annular disk and at least one annular sleeve.

24. Magnetorheological braking device (1) according to one of the two preceding claims, wherein the shielding device (78) and the magnetic ring unit (71) are arranged at a distance from one another.

25. Magnetorheological braking device (1) according to one of the preceding claims, wherein a closed chamber (110) is formed between the brake components (2, 3), and wherein the second brake component (3) at a first end (111) of the closed chamber ( 110) is rotatably received on the first brake component (2), the closed chamber (110) being essentially filled with the magnetorheological medium (6).

26. Magnetorheological braking device (1) according to one of the preceding claims, wherein a rotary knob (23) or a rotary wheel is formed on the casing part (13).

27. Magnetorheological braking device (1) according to one of the preceding claims, wherein the jacket part (13) comprises a sleeve part (13) made of a magnetically conductive material and provides an outer ring (24) for the magnetic field.

28. Magnetorheological braking device (1) according to one of the preceding claims, wherein magnetic field strengths of greater than 350 A / m are generated in the gap

29. Device component (200) with a magnetorheological braking device (1) according to one of the preceding claims.

30. Device component (200) according to the preceding claim, comprising at least one user interface (43) Control panel, a display, a touch-sensitive display with or without haptic feedback and / or at least one sensor.