MAGNETORHEOLOGICAL BRAKE DEVICE, IN PARTICULAR AN OPERATING DEVICE

Abstract

A magnetorheological brake device for adjusting operating states by way of rotational movements includes an axle unit and a rotary body that can be rotated relative to the axle unit. A torque for the rotation of the rotary body can be varied in a targeted manner by a magnetorheological brake. A sensor device functions to detect a rotational position of the rotary body and includes a magnet ring unit and a magnet field sensor rotationally fixed to the axle unit and arranged radially and/or axially next to the magnet ring unit. The magnet field sensor is also arranged at least partially within the axle unit.

Claims

1-19. (canceled)

20. A magnetorheological brake device, comprising: an axle unit and a rotary body rotatably mounted relative to said axle unit; a magnetorheological braking apparatus configured to selectively adjust a torque for a rotatability of said rotary body; a sensor device disposed to detect a rotary position of said rotary body, said sensor device including at least one magnetic ring unit and at least one magnetic field sensor arranged radially and/or axially next to said magnetic ring unit, said at least one magnetic field sensor being rotationally affixed to said axle unit and arranged at least partially inside said axle unit.

21. The magnetorheological brake device according to claim 20, wherein said axle unit comprises at least one axle portion which at least in portions radially surrounds said magnetic field sensor, and wherein the axial portion has a lower magnetic conductivity than a core cooperating with an electrical coil of said braking apparatus.

22. The magnetorheological brake device according to claim 20, wherein said magnetic ring unit is arranged on an axial end face of said rotary body.

23. The magnetorheological brake device according to claim 20, wherein at least portions of said magnetic ring unit surround at least one of said magnetic field sensor or said axle unit annularly.

24. The magnetorheological brake device according to claim 20, wherein said magnetic ring unit and said magnetic field sensor are arranged coaxially to one another.

25. The magnetorheological brake device according to claim 20, wherein said magnetic field sensor is arranged in a bore formed in said axle unit and wherein an electrical connection of said braking apparatus also runs through said bore.

26. The magnetorheological brake device according to claim 20, wherein said magnetic field sensor is arranged on a circuit board, said braking apparatus is electrically connected to said circuit board, wherein at least one connecting line for contacting said brake device is connected to said circuit board, and said circuit board is arranged inside said axle unit and the connecting line extends out of said axle unit.

27. The magnetorheological brake device according to claim 20, wherein said magnetic field sensor is encased with potting material in said axle unit, and/or wherein said circuit board is encased with potting material in said axle unit.

28. The magnetorheological brake device according to claim 20, wherein at least portions of said magnetic ring unit surround said axle unit in a ring shape.

29. The magnetorheological brake device according to claim 20, which further comprises at least one wedge bearing device configured to selectively decelerate or block said rotary body, wherein said wedge bearing device is arranged axially between said magnetic ring unit and a coil unit of said braking apparatus.

30. The magnetorheological brake device according to claim 20, wherein at least one of said magnetic field sensor or said magnetic ring unit is arranged on an end face of said rotary body which also lies on an end face of said axle unit from which at least one signal line of said magnetic field sensor emerges, wherein the signal line does not run through a magnetic field of said braking apparatus.

31. The magnetorheological brake device according to claim 20, wherein said magnetic field sensor and said magnetic ring unit are arranged on an end face of said rotary body opposite an end face of said axle unit from which at least one signal line of said magnetic field sensor emerges, and wherein the signal line is an optical line for optical signal transmission.

32. The magnetorheological brake device according to claim 31, wherein the signal line is, at least in portions, formed by a bore in said axle unit so that said axle unit itself serves as a light wave guide.

33. The magnetorheological brake device according to claim 20, wherein at least one of said magnetic ring unit or said magnetic field sensor is arranged inside a radial circumferential line delimited by said rotary body.

34. The magnetorheological brake device according to claim 20, wherein said magnetic ring unit is arranged outside a receiving chamber delimited by said rotary body, and wherein at least one sealing device is arranged between said magnetic ring unit and said rotary body, which bears sealingly on said rotary body and said axle unit in order to prevent a magnetorheological medium to leak from said receiving chamber.

35. The magnetorheological brake device according to claim 20, which comprises a magnetically conductive wall arranged between said magnetic ring unit and said braking apparatus.

36. The magnetorheological brake device according to claim 35, wherein said wall is at least partially provided by an end wall of said rotary body, and/or wherein said wall at least partially closes an open end face of said rotary body, and/or wherein said wall is configured as a support structure for said sealing device.

37. The magnetorheological brake device according to claim 20, wherein said magnetic field sensor is arranged inside a receiving chamber delimited by said rotary body, and wherein said magnetic field sensor is separated by a sealing unit from a magnetorheological medium arranged in said receiving chamber.

38. The magnetorheological brake device according to claim 20, wherein said magnetic field sensor is configured for detecting the rotary position of said rotary body and an axial position of said rotary body relative to said axle unit.

39. The magnetorheological brake device according to claim 20 in a magnetorheological operating device for adjusting operating states by way of rotational movements via said rotary body.

Description

[0081] The figures show:

[0082] FIG. 1 a purely schematic illustration of a brake device according to the invention in a cut-away side view;

[0083] FIGS. 2-4 purely schematic illustrations of further embodiments of the brake device in cut-away side views;

[0084] FIG. 5 a purely schematic illustration of an axle unit of a brake device according to the invention in a cut-away side view;

[0085] FIGS. 6-7a purely schematic illustrations of further brake devices in cut-away side views;

[0086] FIGS. 7b-7d detail views of the brake device from FIG. 7a;

[0087] FIG. 7e a schematic illustration of a development of a sensor signal; and

[0088] FIGS. 8a-8e schematic three-dimensional views of brake devices.

[0089] FIG. 1 shows a brake device 1 according to the invention which is here configured as an operating device 100 and has a rotatable rotary body 3, configured as a finger roller 23 or thumb roller 102, for adjusting operating states. Operation thus takes place here at least by turning the rotary body 3.

[0090] The rotary body 3 is here rotatably mounted on an axle unit 2 by means of a bearing device (not shown in detail here). The axle unit 2 here forms a first brake component 2 and the rotary body forms the second brake component 3. The rotary body 3 may also be rotatably mounted on an axle unit 2 by means of a wedge bearing device 6, here configured as a roller bearing. Preferably however, the wedge bearing device 6 is not or is only partially provided for the mounting 22 of the rotary body 3 on the axle unit 2, but serves for the braking apparatus 3 presented below. The roller bodies of the wedge bearing device 6 here serve as the braking bodies 44 described in more detail below.

[0091] The axle unit 2 may be mounted on an object to be operated and for example in an interior of a motor vehicle or on a medical device or Smart device. For this, the axle unit 2 may here comprise mounting means (not shown in detail).

[0092] It may be provided here that the rotary body 3 is also movable on the axle unit 2 in the longitudinal direction or along the rotational axis. Then operation takes place both by turning and by pressing and/or pulling or moving the rotary knob 3.

[0093] The rotary body 3 is here configured as a sleeve and comprises a cylindrical wall and an end wall integrally connected thereto. The axle unit 2 emerges from an open end side of the rotary body 3.

[0094] The finger roller 23 may be equipped with an additional part 33 (indicated here in dotted lines). This increases the diameter in order to facilitate rotatability, for example in the case of a wheel rotatable by one finger on a computer mouse 103 or game controller, in particular a game pad 105, or a rotary control on a computer keypad thumb roller 102.

[0095] The rotational movement of the rotary knob 3 is here damped by a magnetorheological braking apparatus 4 arranged in a receiving chamber 13 inside the rotary knob 3. A coil unit 24 of the braking apparatus 4 generates a magnetic field which acts on a magnetorheological medium 34 situated in the receiving chamber 13. This leads to a local strong cross-linking of magnetically polarizable particles in the medium 34. The braking apparatus 4 thereby achieves a targeted deceleration and even complete blocking, and in particular also a targeted release of the rotational movement. Thus with the braking apparatus 4, a haptic feedback during the rotational movement of the rotary body 3 can be achieved, for example by a correspondingly perceptible latching or by dynamically adjustable stops.

[0096] For supply and actuation of the coil unit 24, the braking apparatus 4 here comprises an electrical connection 14 which is configured for example in the manner of a circuit board 35 or printed circuit board or cable line. The connecting line 11 here extends through a bore 12 running in the longitudinal direction of the axle unit 2.

[0097] The receiving chamber 13 is here sealed towards the outside by a sealing device 7 and a sealing unit 17 in order to prevent an emergence of the medium 34. The medium 34 is here a magnetorheological medium 34. The sealing device 7 here closes the open end face of the rotary body 3. For this, a first sealing part 27 bears on the inside of the rotary body 3. A second sealing part 37 bears on the axle unit 3. The sealing parts 27, 37 are here attached to and/or configured as a support structure configured as a wall 8.

[0098] The sealing unit 17 is here configured as an O-ring and radially surrounds the axle unit 3. The sealing unit 17 lies against the axle unit 2 and the rotary body 3. In this way, the part of the receiving chamber 13 filled with the medium 34 is sealed against another part of the receiving chamber 13.

[0099] In order to monitor the rotary position of the rotary body 3 so as to be able to actuate the braking apparatus 4, here a sensor device 5 is provided. The sensor device 5 comprises a magnetic ring unit 15 and a magnetic field sensor 25.

[0100] The magnetic ring unit 15 is here diametrically polarized and has a north pole and a south pole. The magnetic field sensor 25, here configured as a Hall effect sensor, measures the magnetic field emitted by the magnetic ring unit 15 and thus allows reliable determination of the rotary angle.

[0101] Also, the magnetic field sensor 25 is here preferably configured three-dimensionally, so that in addition to rotation, an axial movement of the rotary body 3 relative to the axle unit 2 can be measured. In this way, both the rotation and a pushbutton function (push/pull) can be measured simultaneously with the same magnetic field sensor 25. The brake device 1 may however also be equipped with just a rotational function.

[0102] The sensor device 5 is particularly advantageously integrated in the brake device 1. For this, the magnetic field sensor 25 is here inserted in the bore 12 of the axle unit 2. The magnetic ring unit 15 radially surrounds the magnetic field sensor 25 and is attached to the rotary body 3. This has the advantage that no length tolerances apply, but only precisely producible diameter tolerances. The radial bearing gap between the rotating rotary body 3 and the stationary axle unit 2 is correspondingly small and also easily managed in mass production.

[0103] A further advantage is that axial movements or displacements between the rotary body 3 and the axle unit 2 do not unfavorably influence the sensor signal, since measurements are made in the radial direction and it is the radial distance which is substantially decisive for the quality of the measurement signal.

[0104] It is a further advantage that the arrangement shown here is particularly non-sensitive to dirt and liquids since the sensor is arranged on the inside. Also, the magnetic field sensor 25 in the bore 12 may for example be encased in a plastic.

[0105] In order to further improve the accommodation of the magnetic field sensor 25, this is here arranged on a circuit board 35 or printed circuit board. Here, the coil unit 24 or its connection 14 is also contacted on the circuit board 35.

[0106] Furthermore, the connecting line 11, via which the entire brake device is connected to the system to be operated, is also attached to the circuit board 35. Thus for example a 6-pin or 8-pin plug connector may be attached to the circuit board 35, via which both the magnetic field sensor 25 and the coil unit 24 can be connected to the corresponding controller. Here, the signal line 45 for transmitting the sensor signal is also arranged in the connecting line 11.

[0107] Thus the brake device 1 can be installed particularly easily and quickly. In order to make the entire system particularly robust against faults and disturbance, the circuit board 35 may be cast in the bore 12 and the magnetic field sensor 25 in the axle unit 2.

[0108] FIG. 2 shows an embodiment of the brake device 1 which differs from the embodiment described above substantially in the structural accommodation of the sensor device 5. Here, the magnetic ring unit 15 is arranged on the end face of the rotary body 3 which is closed or through which the axle unit 2 does not extend.

[0109] Here, a particularly space-saving accommodation for the magnetic field sensor 25 inside the axle unit and inside the rotary body 3 is provided. For this, the magnetic field sensor 25 is arranged with an active sensor part in the receiving chamber 13. Another part of the magnetic field sensor 25 extends into the axle unit 2 where it is attached. The magnetic field sensor 25 lies in the part of the receiving chamber 13 which is separated from the part with the medium 34 by the sealing unit 17. Here, this part of the receiving chamber 13 lies in a central bulge of the rotary body 3. The magnetic field sensor 25 is here attached to an end face of the axle unit 2.

[0110] The axially offset positioning of the magnetic ring unit 15 is here shown highly schematically, and this may for example also lie more closely against the rotary body 3 so that the magnetic ring unit 15 surrounds the magnetic field sensor 25 in the manner of a ring.

[0111] In the embodiment shown here, the magnetic field sensor 25 is arranged on the end face of the rotary body 3 which lies opposite the outlet side for the signal line 45 or connecting line 11. Therefore, here the sensor signal is conducted through the bore 12 in the axle unit 2 to the opposite side and must therefore pass through the magnetic field of the coil unit 24.

[0112] In order to avoid disruption of the signal, the signal transmission here takes place optically. For this, the light signal is here simply radiated through the bore 12 of the axle unit 2. It may however also be provided that the signal line 45 is configured as a light wave guide at least in the region of the coil unit 24. For sending and receiving signals, corresponding photodiodes (not shown in detail here) are provided.

[0113] FIG. 3 shows an embodiment which differs from the embodiments previously described substantially in structural design of the axle unit 2. Here, the axle unit 2 comprises an axle portion 415 which radially surrounds the magnetic field sensor 25. The axle portion 415 has a lower magnetic conductivity than a core 21, which here carries a winding of the electrical coil 24 of the braking apparatus 4. Thus the magnetic field of the magnetic ring unit 15 can penetrate the axle unit 2 particularly well in the region of the magnetic field sensor 25, so that an improved sensor resolution is possible.

[0114] Here, the core 21 provides a supporting second axle portion 425 of the axle unit 2. For this, the axle portions 415, 425 are here fixedly connected together and e.g. screwed together. The axle portions 415, 425 are here dimensioned such that the sealing part 37 bears on the core 21. Since the core 21 here consists of a harder material than the axle portion 415, any running of the sealing part 37 onto the axle unit 2 is reliably avoided.

[0115] FIG. 4 shows an embodiment of the axle unit 2 in which the second axle portion 425 radially surrounds the first axle portion 415 in portions. The second axle portion 425 is here again provided by the core 21 for the coil 24. The first axle portion 415 is formed exposed in the axial region of the magnetic field sensor 25. So the magnetic field sensor 25 is there not shielded by the core 21. In the region of the braking apparatus 4, the second axle portion 425 or the core 21 then radially surrounds the first axle portion 415. In this way, the core 21 can be mounted particularly simply.

[0116] In the embodiments shown in FIGS. 1 to 4, the wall 8 is configured so as to be magnetically conductive. This may prevent the magnetic field of the magnetic ring unit 15 and the magnetic field of the coil unit 24 from unfavorably influencing one another. For example, the wall 8 is made of a metal which shields a magnetic field, and for example from a metal with a relative magnetic permeability of at least 100,000. For example, the wall 8 is made of a nickel-iron alloy. At the same time, the wall 8 here serves as a connection for the sealing device 7. In order to shield the magnetic field of the magnetic ring unit 15 shown in FIG. 2 from the magnetic field of the coil unit 24, there the end face of the rotary body 3 is made of a magnetically conductive material.

[0117] FIG. 5 shows a detail illustration of an axle unit 2 which here consists of three axle portions 415, 425, 435. A first axle portion 415 serves as a receiver for the magnetic field sensor 25, and for this is designed as described before with reference to FIGS. 3 and 4. Connected to this is a second axle portion 425 which is formed by the core 21. Adjoining this is a third axle portion 435 which forms the axial end of the axle unit 2. Thus for example the rotary body 3 may be attached to the third axle portion 435. It is also possible that a further core 21 adjoins the third axle portion 435. Thus a correspondingly extensive magnetic field can be produced with a strong braking effect.

[0118] FIG. 6 shows a brake device according to the invention with a shielding device 9 for shielding the sensor device 5 from the magnetic field of the coil unit 24 of the braking apparatus 4. The brake device 1 shown here differs from the brake devices 1 described above not only in the shielding device 9 but in particular also by the design of the rotary body 3 and the additional part 33. The brake device 1 shown here is for example a mouse wheel 106 of a computer mouse 103 or a finger roller 23 or a thumb roller 102.

[0119] The rotary body 3 is here configured as a cylindrical sleeve and on its outside is completely surrounded by the additional part 33. The additional part 33 here terminates the rotary body 3 at the radial end face which faces away from the magnetic ring unit 15.

[0120] The additional part 33 has a radially circumferential protrusion with a substantially enlarged diameter. This makes the brake device 1 shown here particularly suitable for a mouse wheel 106 of a computer mouse 103 or similar. The protrusion is here configured with a groove in which a particularly grippy material, e.g. rubber, is embedded.

[0121] The brake device 1 shown here has two wedge bearing devices 6 spaced apart from one another. The wedge bearing devices 6 are each equipped with several braking bodies 44 arranged radially around the axle unit 2. The coil unit 24 is arranged between the wedge bearing devices 6. The braking bodies 44 are here for example roller bodies which roll on the inside of the rotary body 3 or on the outside of the axle unit 2, or are arranged there, and have a slight and in particular minimal distance from the outside of the axle unit.

[0122] The magnetic ring unit 15 is coupled rotationally fixedly to the rotary body 3 so that the magnetic ring unit 15 co-rotates on rotation of the rotary body 3. The magnetic field sensor 25 is here inserted in the bore 12 of the axle unit 2. The magnetic ring unit 15 surrounds the magnetic field sensor 25 radially and is arranged axially on the end. The magnetic field sensor 25 is here arranged with an axial offset from the axial center of the magnetic ring unit 15. This gives a particularly high-resolution, reproducible sensing of the axial position of the rotary body 3 relative to the axle unit 2.

[0123] The shielding device 9 comprises a shielding body 19, here configured as a shielding ring 190. The shielding device 9 also comprises a separating unit 29 which is here provided by a gap 290 filled with a filling medium 291. Also, the shielding device 9 comprises a magnetic decoupling device 39 which is here provided by a decoupling sleeve 390 and a decoupling gap 391.

[0124] The decoupling sleeve 190 here comprises an axial wall 392 on which the sealing device 7 is arranged. Also, a bearing device 22 (not shown here in detail) may be arranged on the axial wall 392.

[0125] The shielding body 19 here has an L-shaped cross section and is made of a magnetically particularly conductive material. The shielding body 19 surrounds the magnetic ring unit 15 on its radial outside and on its axial side facing the coil unit 24. For magnetic decoupling, the gap 290 is arranged between the shielding body 19 and the magnetic ring unit 15 and filled with a filling medium 291. The filling medium 291 has a particularly low magnetic conductivity. Also, the magnetic ring unit 15 is attached to the shielding body 19 via the filling medium 291.

[0126] A magnetic decoupling between the rotary body 3 and the shielding body 19 is achieved by the decoupling device 39. For this, the decoupling sleeve 390 and a filling medium 291, arranged in the decoupling gap 391, also have a particularly low magnetic conductivity. The decoupling sleeve 391 is here rotationally fixedly connected to the shielding body 19 and the additional part 33 and the rotary body 3.

[0127] In order to achieve an even better decoupling of the rotary body 3 from the sensor device 5, the rotary body 3 is here arranged axially spaced from the decoupling sleeve 390. The end of the rotary body 3 facing the magnetic ring unit 15 here does not protrude beyond the braking body 44. Also, the rotary body 3 is axially set back or shortened relative to the additional part 33. This gives a particularly advantageous magnetic and physical separation of the rotary body 3 and decoupling sleeve 390 in a very small installation space.

[0128] Since the magnetic field of the coil unit 24 for the braking effect flows via the rotary body 3, such an embodiment offers a particularly good shielding. So that this magnetic flux has as little influence as possible on the magnetic field sensor 25, the rotary body 3 terminates earlier in the axial direction and the magnetically non-conductive additional part 33 takes over the structural functions (bearing point, sealing points etc.). The distance from the magnetic field sensor 25 is thereby even greater and the assembly as a whole is lighter.

[0129] The rotary body 3 is made from a magnetically particularly conductive material. The additional part 33 and the decoupling sleeve 390 are however made of a magnetically non-conductive material. The shielding body 19 and the rotary body 3 are here made for example from a p metal. The components described here as magnetically non-conductive consist for example of plastic and have a relative magnetic permeability of less than 10.

[0130] The problematic fields which can often disrupt the rotary angle measurement are above all the fields in the radial direction. These fields are here shielded by a shielding body 19 of suitable material, e.g. magnetically conductive steel, acting as a jacket. In addition, the magnetic field of the magnetic ring unit 15 may thus be further amplified. As a result, the magnetic ring unit 15 may be made smaller (thinner) and hence material, installation volume and production costs can be saved.

[0131] The construction according to the invention is improved in that the wall thickness of the shielding body 19 is varied, and a gap 290 is provided between the magnetic ring unit 15 and the shielding body 19. The shielding and the amplification may be optimally adapted by the gap 290 between the magnetic ring unit 15 and the shielding body 19. The material of the shielding body 19 is here selected such that it does not go into magnetic saturation, so external magnetic fields can be adequately shielded (material in saturation allows the passage of magnetic fields in the same way as air, i.e. with a magnetic field constant of μ0). With an advantageous design of the gap 290 between the magnetic ring unit 15 and the shielding body 19, the magnetic field does not close too strongly via the shielding body 19, and the field in the center with the magnetic field sensor 25 is sufficiently homogenous and is increased compared with a magnetic ring unit 15 of the same or larger size without shielding body 19.

[0132] The dimensioning of the shielding device 9 shown here is particularly suitable for a mouse wheel 106 of a computer mouse 103, and for example has the following dimensions. The shielding ring 190 is 0.5 mm thick, the distance between the shielding ring 190 and the magnetic ring unit 15 is also 0.5 mm, the width of the magnetic ring unit 15 is 2 mm, and the diameter of the magnetic ring unit 15 is 8 mm. In this case, the possible interference field of the coil unit 24 is 140 μT, giving a possible error in angular measurement of 0.1° (cf Earth's magnetic field: approximately 48 μT in Europe).

[0133] FIG. 7a shows a variant in which a push-pull function is integrated. A button 474 may be actuated and is automatically reset. The diameters of the two bearing points 412, 418 are here selected to be the same size. As a result, on an axial movement of the first brake component 2 (corresponding to the axle unit) relative to the second brake component 3 (corresponding to the rotary body), the volume inside the chamber does not change. A movement of the first brake component 2 to the left in the orientation of FIG. 7a leads to an increase or change in the distance of the magnetic field sensor 25 from the magnetic ring unit 15.

[0134] An axial movement causes a change in the signal 468 received, as illustrated in FIG. 7e. FIG. 7e shows the curve of the amplitude 469 of the signal 468 detected by the magnetic field sensor 25 as a function of the axial movement of the brake components 2, 3 (horizontal axis). An axial movement of the magnetic field sensor 25 relative to the magnetic ring unit 15 changes the amplitude 469 of the detected signal 468. An axial movement or pressing down of the additional part 33, or a sideways movement of the additional part 33, can thus be detected. The same magnetic field sensor 25 can also detect the rotary angle, wherein to detect the rotary angle, the direction of the magnetic field is determined. The intensity determines the axial position. Therefore, a change in the signal 468 indicates an axial actuation of the brake device 1 or button 474. This is advantageous since a single (multi-dimensional) Hall effect sensor can be used for determining the angular position and for determining an axial position.

[0135] In FIG. 7a, the first brake component 2 is arranged inside the second brake component 3, and is held by form fit and/or force fit by a holder 404. The holder 404 may for example be attached to an external bracket or a device. The holder 404 is usually attached rotationally fixedly. The second brake component 3 is received on the first brake component 2 so as to be continuously rotatable relative thereto.

[0136] The bracket 404, as shown in FIGS. 7b and 7c, may preferably be formed in two pieces. This simplifies above all installation of the electrical lines and in particular of the sensor line 45 inside the first brake component 2. The cables can be laid through the here open cable passage or bore 12. FIG. 7d shows the sensor device 3 again in detail. The first brake component 2 and the second brake component 3, here configured as a rotary part, are merely indicated (dotted lines). The sensor device 5 here rests via the decoupling device 39 on the rotatable second brake component 3 in a magnetically decoupled fashion. The shielding device 9 here consists of a three-piece shielding body 19. In addition, a separating unit 29 is also provided for magnetic separation. The magnetic ring unit 15 is used for measuring the orientation or rotary angle of the magnetorheological braking apparatus 1. The magnetic field sensor 25 is arranged inside the first brake component 2. Small relative axial movements can also be used to detect e.g. when an operating knob 101 is pressed down.

[0137] FIGS. 8a to 8f show devices which are equipped with the invention. The brake devices 1 here are each configured as haptic operating devices 100.

[0138] FIG. 8a shows a haptic operating knob 101. The operating knob is attached via a bracket 50. The operating knob 101 is here operated via the sleeve part. The user interface may also be used to transmit information.

[0139] In FIG. 8b, the brake device 1 is formed as a thumb roller 102 with haptic operating device 100. The thumb roller 102 can preferably be used for example in steering wheels. The thumb roller 102 is not however restricted to this application. The thumb roller 102 may in general also be usable with another finger depending on installation situation.

[0140] FIGS. 8c and 8d show the brake device 1 according to the invention as a mouse wheel 106 of a computer mouse 103. The magnetorheological brake device 1 may be used to control a haptic feedback.

[0141] FIG. 8e shows a joystick 104 with a brake device 1 as a haptic operating device 100. FIG. 8f shows a game pad 105 with the brake device 1 in order to give the player a haptic feedback depending on the game situation.

[0142] The preferably low-alloy steel may retain a residual magnetic field. The steel is preferably demagnetized regularly or as required (e.g. by a special alternating field).

[0143] Preferably, the material FeSi3P (silicon steel) or a related material is used for the components through which the magnetic field flows.

[0144] In all cases, a voice control or sound control may also be implemented. The braking apparatus may be adaptively controlled by voice control.

[0145] If the rotary unit is not being turned, i.e. the angle is constant, preferably the current is continuously reduced over time. The current may also be varied speed-dependently (rotary angular speed of rotary unit).

[0146] The principle of the sensor structure presented is not restricted to purely magnetorheological rotary dampers, but may also be applied to any device with rotatable parts in which a particularly advantageous measurement of the rotary angle is desired.

LIST OF REFERENCE SIGNS

[0147] 1 Brake device [0148] 2 Axle unit [0149] 3 Rotary body [0150] 4 Braking apparatus [0151] 5 Sensor device [0152] 6 Wedge bearing device [0153] 7 Sealing device [0154] 8 Wall [0155] 9 Shielding device [0156] 11 Connecting line [0157] 12 Bore [0158] 13 Receiving chamber [0159] 14 Connection [0160] 15 Magnetic ring unit [0161] 17 Sealing unit [0162] 19 Shielding body [0163] 21 Core [0164] 22 Bearing device [0165] 23 Finger roller [0166] 24 Coil unit [0167] 25 Magnetic field sensor [0168] 27 Sealing part [0169] 29 Separating unit [0170] 33 Additional part [0171] 34 Medium [0172] 35 Circuit board [0173] 37 Sealing part [0174] 39 Decoupling device [0175] 44 Braking body [0176] 45 Signal line [0177] 50 Bracket [0178] 100 Operating device [0179] 101 Operating knob [0180] 102 Thumb roller [0181] 103 Computer mouse [0182] 104 Joystick [0183] 105 Game pad [0184] 106 Mouse wheel [0185] 190 Shielding ring [0186] 226 Latching point [0187] 228 End stop [0188] 229 End stop [0189] 237 Angular distance [0190] 238 Stop moment [0191] 239 Latching moment [0192] 240 Base moment [0193] 290 Gap [0194] 291 Filling medium [0195] 390 Decoupling sleeve [0196] 391 Decoupling gap [0197] 392 Axial wall [0198] 404 Holder [0199] 412 Bearing point [0200] 415 Axle portion [0201] 416 Diameter [0202] 417 Diameter [0203] 418 Bearing point [0204] 425 Axle portion [0205] 435 Axle portion [0206] 448 Slide ring guide [0207] 468 Signal [0208] 469 Amplitude [0209] 474 Button