MRF braking device, drive train arrangement equipped therewith and computer program product and use

Abstract

MRF braking device (10) configured to apply a braking torque (M10) by means of magnetorheological fluid (3), MRF, in particular in a drive train, comprising a rotor (12), in particular a T-shaped rotor with magnetic separation (12.1), comprising a coil (13) and at least one permanent magnet (14), PM, implemented to inhibit sedimentation, wherein the rotor (12) rotates in a geometrically and volumetrically predefined MRF region (15) filled with MRF (3), wherein the coil (13) and the at least one PM (14) are arranged relative to one another in such a way that a minimum cross-sectional area (A1) is ensured for forming a / the closed magnetic circuit caused by the coil (13), wherein the MRF braking device (10) is configured to apply a / the braking torque by energizing the coil (13);characterized in that the MRF braking device (10) is designed to level out a residual friction torque (M3) caused by the PM field by energizing, in particular counter-polar energizing, the coil (13) in a controlled / regulated manner for at least temporarily canceling the PM field for at least one operating situation (BS) detected in particular by means of the MRF braking device by setting at least one magnetic operating state (BZ) of the MRF braking device (10) as a function of at least one parameter (P) or at least one instantaneous parameter value;

Description

TECHNICAL FIELD

[0001] The present invention relates to an MRF braking device for applying a braking torque by means of magnetorheological fluid, MRF, in particular in a drive train, comprising a rotor, in particular a T-shaped rotor with magnetic separation, comprising a coil and at least one permanent magnet, PM, implemented to inhibit sedimentation, wherein the rotor rotates in an MRF-filled MRF region that is geometrically and dimensional or volumetrically predefined and has at least one predefined gap thickness, wherein the coil and the at least one PM are arranged relative to one another in such a way that a minimum cross-sectional area is ensured for forming a closed magnetic circuit caused by the coil, wherein the MRF braking device is configured to apply a braking torque by energizing the coil.Furthermore, the present invention relates to implementation measures for the realization of a method for the controlled / regulated application of a braking torque by means of an MRF braking device equipped with at least one permanent magnet, PM, in particular in a drive train, wherein, on the one hand, a specific magnetic operating state of the MRF braking device and, on the other hand, the currently desired operating mode, e.g., depending on a load situation and / or rotational speed of the drive train, are predetermined by control / regulation technology, in particular in connection with control / regulation technology leveling of the PM field. Last but not least, the present invention also relates to the use of control / regulation means for setting an operating mode depending on a current operating situation and a current magnetic operating state.In particular, the invention relates to devices and uses according to the preamble of the respective independent claim. BACKGROUND OF THE INVENTION

[0002] For MRF brakes operating using magnetorheological fluid (MRF), particularly for drivetrains, it is important, on the one hand, to find a favorable compromise, particularly between design complexity, number of components, required MRF volume (and the associated costs), braking effect, friction minimization, service life, and installation space requirements. On the other hand, there is interest in the most advantageous adjustment option with regard to the operating conditions and the (braking) characteristics of the MRF brake.

[0003] According to the state of the art, from a design perspective, particularly with a view to high efficiency, it is assumed that the rotor should have the largest possible surface area interacting with the MRF, in particular in the radially outer region, and in particular a T-shape. Such rotors entail certain geometric and design constraints, e.g. with regard to the spatial arrangement of magnets acting on the MRF. However, MRFs can have the disadvantage that the particles they contain settle over time, particularly if there is little to no mixing of the MRF. This can lead to the desired braking effect not being generated or at least only being noticeably reduced, particularly during a restart phase, especially if the MRF brake is not in use for extended periods (particularly with only sporadic rotation or without any rotation of the drive train).In addition to reducing the transmittable torque, such configurations can also result in uneven torque transmission. This also brings with it safety-related disadvantages.

[0004] It is already known that at least one permanent magnet (PM), particularly installed on the stator, can prevent the sedimentation of particles trapped in the MRF. However, this has the disadvantage that a noticeable residual friction torque occurs because the PM field acts (permanently) on the MRF. However, omitting at least one PM would be equally disadvantageous for many applications, especially since the PM can be advantageously implemented in conjunction with a coil or an electromagnet in such a way that the best possible uniform distribution of the magnetic field can be ensured, thus potentially contributing to an optimization of the magnetic field.

[0005] In particular for rotors and magnets that are geometrically optimized with regard to braking effect and arranged accordingly, there is interest in an improved way of realizing a symbiosis of the above-mentioned requirements in the context of at least one installed PM, in particular with regard to the control / regulation of the operating behavior or the (braking) characteristics of the MRF brake, in particular also specifically for different operating situations or for situation-dependent different requirements.

[0006] As an example, the publication EP 1 595 086 B1 can be mentioned, which describes a magnetorheological arrangement for comparatively strict requirements on efficiency and installation space, in which the space filled with magnetorheological fluid is structurally predefined, whereby the highest possible and evenly distributed controllable magnetic field strength should be achievable in this space.

[0007] Based on the current state of the art, there is a clear need for further optimization, particularly with regard to efficiency, service life, installation space requirements, and friction minimization in MRF brakes, while simultaneously ensuring the greatest possible variability with regard to situation-dependently adjustable braking characteristics. Last but not least, with a view to meeting at least application-specific high safety standards, there is interest in a highly reliable and fail-safe way of implementing MRF technology for braking systems that are as space- and braking-efficient as possible, particularly in drivetrains with high fail-safe requirements. SUMMARY OF THE INVENTION

[0008] The object is to provide an MRF braking device for drive trains equipped with at least one PM, in particular for drive train technology, by means of which on the one hand a comparatively high braking effect can be achieved by means of the MRF, in particular with regard to the required or available installation space, and on the other hand a residual friction torque caused in particular by the at least one PM can be leveled out as completely as possible, wherein the respective drive train should also be able to be operated in the most advantageous manner possible in different operating situations, with advantageously adjustable braking characteristics.It is also the task of designing implementation measures for a braking torque application method, particularly one that can be implemented using such an MRF braking device, in such a way that the most advantageous operating behavior of the MRF braking device can be set for different operating states, particularly those caused by the corresponding drive train, in particular with regard to friction minimization, braking effect, and high safety standards. Last but not least, the task is to design such an MRF braking device or a braking torque application method that can be implemented with it in such a way thatto state that an implementation of control / regulation means or control / regulation-based measures can be advantageously realized for as many operating situations as possible, in particular with regard to different braking characteristics, in particular without the area provided for the MRF having to be changed in size or geometry.

[0009] This object is achieved by an MRF braking device according to claim 1 and by implementation measures relating to at least one operating mode realized by the MRF braking device, as well as by a computer program product according to the corresponding independent claim and by uses according to the respective independent use claim. Advantageous developments of the invention are explained in the respective subclaims. The features of the exemplary embodiments described below can be combined with one another unless explicitly stated otherwise.

[0010] Provided is an MRF braking device configured to apply a braking torque by means of magnetorheological fluid, MRF, in particular in a drive train, comprising a rotor, in particular a T-shaped rotor with magnetic separation, comprising a coil and at least one permanent magnet, PM, implemented to inhibit sedimentation, wherein the rotor rotates in a geometrically and volumetrically predefined MRF region filled with MRF, wherein the coil and the at least one PM are arranged relative to one another in such a way that a minimum cross-sectional area is ensured for forming a / the closed magnetic circuit caused by the coil, wherein the MRF braking device is configured to apply a / the braking torque by energizing the coil;

[0011] According to the invention, it is proposed that the MRF braking device is configured to level out a residual friction torque caused by the PM field by energizing, in particular by energizing the coil in a controlled / regulated manner for at least temporarily canceling the PM field for at least one operating situation, BS, detected in particular by means of the MRF braking device, by setting at least one magnetic operating state, BZ, of the MRF braking device as a function of at least one parameter or at least one instantaneous parameter value, in particular during rotation of the drive train or from a minimum threshold value of a rotational speed of the drive train and / or as a function of a rotational position parameter.This enables a beneficial symbiosis with regard to the aforementioned requirements, in particular efficiency, service life, installation space requirements, friction minimization, safety standards, sedimentation inhibition, and flexibility / variability with regard to operating modes and operating situations. A particularly application-specific implementation can also be realized in a comparatively simple manner using the control / regulation technology described here, which can be specifically tailored to the MRF technology, particularly with comparatively little effort regarding application-specific design reviews.

[0012] The term "magnetic circuit" refers specifically to the magnetic field lines that develop locally between the poles of the magnets involved due to the magnetic field induced by PM and / or EM. These magnetic field lines tend to concentrate at narrow, flat areas, which can lead to efficiency losses. Therefore, the design must ensure that a minimum cross-sectional area is available for the magnetic field lines to develop (avoiding narrow areas).

[0013] The braking torque is understood to be the torque generated / generable when the PM field and the EM field are superimposed due to the effect of the MRF, whereby the braking torque, in particular its amount / level, can be predetermined, among other things, by the manner in which the EM field is generated.

[0014] The nominal torque is the maximum applicable braking torque; in the configuration described here, the nominal torque is achieved when the PM field and the EM field are superimposed. The nominal torque can be a product-specific property that defines, for example, the application range of certain types of MRF braking devices.

[0015] The MRF region, together with the rotor arranged therein, has at least one predefined gap thickness which is structurally unchangeable in terms of size and geometry. The term “at least one gap thickness” is to be understood to mean that the gap between the rotor and the walls enclosing the MRF region can vary in size in certain sections, but is / remains predefined, i.e. its size should not be adjusted, but rather has a different size in a radially inner gap section (e.g. radial gap) than in a radially outer gap section (e.g. radial gap or axial gap). The respective gap thickness is therefore structurally unchangeable and is not related to any coupling function or coupling acting on the MRF region.Engagement / disengagement function; a coupling function, in particular an axial adjustment function with respect to the MRF area, is not provided for in the MRF braking device described here.

[0016] If, according to the present disclosure, a coil is mentioned, this is to be understood as a synonym for a correspondingly acting electromagnetic unit or electromagnetic device.

[0017] Personified terms, unless formulated in the neuter form, can refer to all genders within the scope of this disclosure. Any foreign-language expressions or abbreviations used here are standard industry terms (e.g., "Modbus") and are familiar to those skilled in the art. Any German-language terms used / usable synonymously can be indicated here in (parentheses) for the sake of completeness, or vice versa, for example, with regard to the term "microcontroller."

[0018] In other words, the invention also relates to an MRF braking device configured to apply a braking torque by means of magnetorheological fluid, MRF, in particular in a drive train, comprising a rotor, in particular a T-shaped rotor with magnetic separation, comprising a coil (or an electromagnet, EM) and at least one (preferably in an arrangement on / in the stator) permanent magnet, PM, implemented to inhibit sedimentation, wherein the rotor rotates in a geometrically and sized predefined area filled with MRF with at least one predefined gap thickness (in the case of a T-shaped rotor, therefore with both an axial and a radial gap for the MRF), wherein the coil and the at least one PM are arranged relative to one another in such a way,that a minimum cross-sectional area (meaning cross-sectional area) is ensured for forming a closed magnetic circuit within the MRF braking device caused by the coil for the purpose of the highest possible braking effect (i.e. the largest possible achievable braking torque) (in particular for the purpose of the most evenly distributed magnetic flux density in the minimum cross-sectional area, i.e. to avoid a magnetic bottleneck), wherein the MRF braking device is designed to apply a braking torque by energizing the coil (i.e. essentially by energizing the coil, in particular in cooperation with the PM), in particular purely force-locked based on the magnetorheological (shear) forces induced by the MRF in response thereto; wherein the MRF braking device is designed to apply a residual friction torque caused by the PM field (permanent magnetic field) by energizing,In particular, counterpolar current flow to the coil can be controlled / regulated to ensure at least temporary elimination of the PM field, especially during rotation, thus ensuring at least nearly load-free operation (residual friction preferably <1% of the maximum achievable braking torque). This also enables the fulfillment of numerous requirements, particularly in the context of drive train systems, whose operating conditions can be highly varied.

[0019] Last but not least, controlled / regulated leveling also enables an advantageous transition from a stationary or rather static arrangement of the drive train (first operating situation) to a dynamic operating state or to a rotating operating situation (second or further operating situation) with possibly non-uniform rotation and / or load. In this respect, a rate of change of at least one parameter (when considering the course or curve of the parameter, i.e. the gradient) can be recorded and evaluated for open-loop / closed-loop control, in particular based on a rate of change parameter, e.g., relating to the rotational speed. In addition, at least one of the other parameters described here or a related change, rate of change, or threshold value can be taken into account.

[0020] The implementation of an MRF braking function may be relatively straightforward, especially if the type of load on a drive train and the type of braking function to be activated can be largely predefined. However, for many applications or drive trains, the operating mode cannot be specified within narrow ranges, or the possibility of deviating operating situations occurring cannot be ruled out. Particularly when a high level of safety is required, it may be of great benefit to be able to respond to the respective operating situation in a flexible and variable manner using control technology that ensures the desired braking effect, especially within the shortest possible response times.The present invention therefore also promotes early / rapid and precise detection of different operating situations and enables situation-specific adjustment of the respective magnetic operating state of the MRF braking device, whereby further optimizations can be carried out in the respective magnetic operating state, in particular control / regulation optimizations, e.g. with regard to particularly high braking efficiency and / or with regard to particularly low residual friction values.

[0021] The MRF braking device is advantageously configured to level out a residual friction torque caused by the PM field or by the MRF in the PM field by energizing the coil, in particular by energizing it in opposite polarity, in a controlled / regulated manner, for at least temporarily canceling the PM field for at least one operating situation, particularly detected by the MRF braking device, by adjusting at least one magnetic operating state of the MRF braking device as a function of at least one parameter, in particular during rotation of the drive train or above a minimum threshold value of a drive train speed. This also facilitates advantageous implementation in drive trains used and loaded in different ways, whereby the braking function can be maintained or provided with good effectiveness and safety, largely independent of the call or request time.

[0022] For example, the maximum applicable braking torque (nominal torque), particularly when the PM field and EM field act in concert, is advantageously at least a factor of 100 greater than the residual friction torque leveled off when energized in opposite poles, more preferably at least a factor of 125. The leveling of the frictional braking effect caused by MRF can also be achieved when the magnetic field no longer extends to the MRF region or to the gaps filled with MRF. In other words: The PM can remain magnetically effective in a certain spatial area even during energization in opposite poles, but this spatial area is severely limited by the superimposed magnetic field of the EM and no longer extends (or at least not noticeably) to the rotor or MRF region as intended.

[0023] The at least one permanent magnet, PM, is advantageously arranged / aligned and dimensioned with regard to permanent magnet force such that the prevailing permanent magnet force in the MRF region is at least in a range that prevents sedimentation of magnetic particles enclosed in the MRF, in particular regardless of a current (rotational) operating situation (or prevents sedimentation even over a downtime, i.e. without rotation or relative rotational movement of the drive train and / or the braking device, of e.g. several days or weeks); preferably, the at least one PM is arranged at least approximately half the radius of the radius of the outer surface of the rotor. It has been shown that this relative position with regard to the rotor and EM / coil enables a particularly advantageous compromise.

[0024] It should be understood that the design described here can very effectively counteract sedimentation even when the drive train is stationary for extended periods, particularly thanks to the comparatively homogeneous magnetic flux density (distribution). Nevertheless, for structural reasons, there may be spatial regions in this or that embodiment in which the magnetic flux is unevenly distributed, i.e., exhibits a somewhat suboptimal, inhomogeneous distribution. Therefore, it is not always possible to speak of a completely homogeneous distribution and the complete exclusion of sedimentation. Based on the present disclosure, the skilled person will be able to implement further application-specific (including structural) optimization measures in this regard.

[0025] The present invention also enables, in particular, an advantageous symbiosis of high braking effect and low friction, preferably at least approximately zero friction (residual friction advantageously below 1% of the maximum achievable braking effect), with the option of an energy-efficient currentless adjustment even during longer downtimes, without compromising high safety standards.

[0026] The present invention therefore particularly relates to designs and operating modes in which high braking efficiency combined with low frictional resistance can / should be ensured, especially even with comparatively limited available installation space. Preventing sedimentation is an important safety aspect that should be ensured in any case, in particular by maintaining a field that stabilizes the MRF or the particles contained therein, so that the installation of at least one PM can be considered a necessary criterion for meeting the requirements described above, especially to avoid continuous current flow.

[0027] It should be understood that the number, arrangement, and geometry of coil(s) or electromagnets, on the one hand, and permanent magnet(s) described here can be varied, both spatially and in terms of the structural design of these components. Those skilled in the art can make variations in this regard based on the present disclosure, for example, in the case of particularly tight application-specific specifications regarding installation space, mass, current consumption, or similar criteria.

[0028] It should also be understood that the manner of operation of the MRF brake should advantageously ensure both an opposing action of PM and EM as well as an equal arrangement or adjustment of PM and EM, in particular in order to be able to achieve a high braking effect (brake activated, drive train is to be braked) in combination with low friction (braking effect deactivated, drive train is not to be braked, running with as little torque as possible) with the smallest possible installation space requirements and a comparatively slim coil.

[0029] If, according to the present disclosure, reference is made to an MRF braking device, this is to be understood in particular as a braking device in which the MRF region is not intended to be changed in size and / or geometry by any, in particular, axial adjusting movements, but in which the components delimiting the MRF region are advantageously arranged and remain arranged relative to one another in a predefined manner, e.g., are screwed together, for example, by components or axial sections of the MRF braking device that are axially fixed to one another. In other words: The MRF region is advantageously predefined geometrically and in size and is unchangeable or does not need to be changed, so that no (axial) coupling or adjusting function needs to be implemented in the context of the size and geometry of the MRF region.It should therefore be understood that a gap / area provided for the MRF (MRF area) is advantageously predefined in size and geometry (at least one gap thickness, e.g. a first radial gap thickness and a first axial gap thickness) and should not or does not need to be changed in this regard in order to be able to specify the magnetic operating states or operating modes described here. It should be understood that pressure compensation elements (e.g. in the form of molded foam bodies) can be provided adjacent to the area for the MRF, which can compensate for a change in volume of the MRF when exposed to heat (e.g. in the case of strong to very strong braking, in particular over a comparatively long period); such pressure compensation elements can advantageously be installed flat / planar adjacent to the gap.

[0030] In the context of the investigations into the implementation of the present invention, particularly for drivetrains, it has also been shown that the operating behavior of the MRF braking device can be adjusted or specified or adapted to a current situation of the drivetrain in a particularly advantageous manner if a control / regulation specification is generated, on the one hand, with regard to the speed and, on the other hand, with regard to at least one further parameter, in particular from the following group for specifying different operating modes: torque, angle of rotation, MRF temperature. Particularly for highly dynamic drivetrains with stringent safety requirements, it is of great benefit if the MRF temperature is monitored with regard to at least one threshold value and a control / regulation specification is always generated taking the MRF temperature into account.For this purpose, the MRF braking system preferably has at least one permanently installed MRF temperature sensor. For example, in highly demanding operating conditions with a high reduction in braking torque over an extended period, it may be advisable to reduce the speed at least temporarily to avoid compromising continuous operation and the safety level.

[0031] It should be understood that a very high proportion of the provided torque can be generated in the radially outermost region of the rotor, particularly due to shearing of an MRF chain structure over a comparatively large, longer lever arm at comparatively high circumferential speeds. A temperature sensor is therefore advantageously positioned as far radially outward as possible.

[0032] The structural design and coordination of the situation-specifically adaptable mode of operation of the PM and coil described here also provides a particularly advantageous compromise between sedimentation inhibition, friction minimization, magnetic field homogeneity, achievable braking torque, response time, and variability with regard to the adjustable (braking) characteristics. For example, the at least one PM is arranged and dimensioned such that, when the PM field is active, a flux density in the mid-double-digit millitesla range is ensured, particularly at least in the primarily relevant sections of the MRF range. This effectively prevents sedimentation even in the de-energized state.

[0033] In order to prevent sedimentation in the de-energized state in a particularly effective manner, the at least one PM according to an exemplary embodiment can also be arranged and dimensioned such that in the MRF area or across the MRF (i.e. across the volume occupied by the MRF) a flux density of approximately 35 to 45 mT, in particular 40 mT (millitesla) prevails, whereby this threshold value can also depend on the application-specific desired safety factor, e.g. should not be less than 30 mT if possible (which in turn also depends on the relative size ratios); the ratio of nominal torque to residual friction torque (essentially determined by the at least one PM, but also by seals and bearings) is then, for example, approximately 100 Nm to 2 Nm or 3 Nm or 2% to 3%.By energizing the coil (electromagnet) to cancel the PM magnetic field, particularly during rotation of the drive train (and the associated mixing of the MRF), the residual friction torque in the configuration described here can be reduced to, for example, <1 Nm or less than 1% of the nominal torque (maximum applicable braking torque).

[0034] If, according to the present disclosure, reference is made to an operating state, this is to be understood as one of the at least three magnetic operating states described here. If, according to the present disclosure, reference is made to an operating mode, this is to be understood as a specific type of control / regulation or a specific selection of a corresponding control / regulation specification in the corresponding currently set magnetic operating state. If, according to the present disclosure, reference is made to an operating situation, this is to be understood in particular as a drive train situation, such as (very broadly subdivided) standstill or rotation.

[0035] It should be understood that an implementation of AI models within the scope of the present invention can also be provided, in particular for the further development of the control / regulation concept described here, for example also with regard to a particularly time-efficient detection of operating situations or load conditions and / or with regard to the evaluation of a large number of parameters and / or performance data supported by machine learning, wherein this AI implementation can also comprise a computer infrastructure or data processing architecture, in particular also in the core of at least one computing unit, which facilitates the execution of ML algorithms centrally directly in / on the hardware, e.g. within the control / regulation unit described here, and / or makes it more powerful or accelerates it (up to real-time processing) and / or makes it more energy-efficient, or at least partially even makes it possible in the first place.In particular, decision-making processes of neural AI networks can be implemented comparatively quickly and (energy) efficiently, especially in end devices (edge) and / or in sensors implemented for the MRF braking system or the respective drive train.For example, the computer-technical and chip-based means described here, in particular also a microcontroller, comprise at least one of the following components: photonic AI chips, in particular with silicon photonic structures (combination of electronic and optical data processing processes), optical waveguides at least partially instead of or at least in addition to electronic semiconductors, as well as multiplexing components, photon modulators, photodetectors, ring resonators, at least one dense wavelength division multiplexing (DWDM) component for the simultaneous processing of multiple data channels, at least one optical circuit integrated into at least one neural network (NN) or into a DNN (deep neural network), and at least one photonic processor. For example, at least one NN and / or DNN is implemented directly at the hardware level. As a result, particularly large amounts of data can be analyzed particularly quickly.Data from larger parameter groups can also be evaluated more quickly and easily, and / or a trend analysis (parameter progression analysis) can be performed more precisely, or a trend can be identified more quickly / earlier / more reliably. Optionally, this type of analysis can also be used to generate a warning signal or implement a trigger for compliance with safety-relevant measures (e.g., reducing the speed). For example, at least one photonic component is printed directly onto a wafer, in particular at least one of the following photonic components: optical amplifiers, photonic integrated circuits (PICs), polarization converters, splitters, optical fibers, splitters, phase modulators.

[0036] In particular, the MRF braking device is designed for at least three magnetically different operating states, namely a first (in particular currentless) magnetic operating state with exclusively PM field without energized coil (in particular with a friction loss component caused in particular by the PM in the lower single-digit percentage range of the nominal torque), a second magnetic operating state with leveled residual friction torque with oppositely polarized energized coil (in particular with a residual friction torque of significantly less than 1% of the nominal torque), and at least a third magnetic operating state with predefined / predefinable braking torque with energized coil, wherein the respective magnetic operating state can be adjusted as a function of a momentary rotation of the rotor by energizing the coil in a speed-dependent manner.

[0037] It should be understood that the at least one gap thickness can also be specified depending on the geometry of the rotor; with the T-shaped cross-sectional geometry of the rotor considered here, at least a first radial gap thickness and a first axial gap thickness are advantageously provided. The axial gap thickness is provided in the region of the radially outer T-section of the rotor, and a particularly large proportion of the transmittable torque occurs in this region. The gap thickness can also influence or extend the service life, in particular of the MRF.The service life can be specified relatively precisely by adhering to certain threshold values ​​for the friction work to be generated by the MRF (in [MJ / ml]). A lower threshold value for the friction work can cover the most disadvantageous scenario for a particularly short service life. An upper threshold value for the friction work, which may be dependent on a safety factor, can be regarded as a recommendation for an (active) service life of the MRF braking device until the MRF is replaced. It has proven advantageous to design the at least one axial gap thickness larger than the at least one radial gap thickness.

[0038] According to one embodiment, the MRF braking device is configured to control / regulate the manner in which a braking torque is applied for at least three magnetically different operating states (BZ) predetermined by the control / regulation system. The respective magnetic operating state can be adjusted at least as a function of the instantaneous rotation of the rotor by applying current to the coil in a speed-dependent manner. This not least facilitates rapid switching of the BZ, at least as a function of the instantaneous rotational speed, and optionally also as a function of the instantaneous torque absorption and / or rotational position.

[0039] According to one embodiment, the MRF braking device is configured to generate a braking torque at least 100 times greater than the residual friction torque that can be leveled by applying current in opposite poles. This range for the factor between residual friction torque and nominal torque (maximum applicable braking torque for a specific type of MRF braking device) provides a favorable degree of torque availability with an advantageously low residual friction torque for the most load-free rotation possible when the braking effect is not required.

[0040] According to one embodiment, the MRF braking device is configured to generate a braking torque at least 50 times greater than the (residual) friction torque prevailing without counter-polar current application. This also provides an advantageous compromise between electromagnetic (braking) capabilities and permanent magnetic function, particularly with regard to sedimentation inhibition.

[0041] According to one embodiment, the setting of at least one magnetic operating state and / or at least one operating mode is implemented by a current-based control / regulation, in particular based on at least one parameter from the following group: speed-based parameter, torque-based parameter, rotational position-based parameter, external parameter such as a force measurement value (e.g. tensile force in a material web of a processing operation). This also improves the system openness and integrability of the MRF braking device in the context of complex processes and, for example, also with regard to the integration of the MRF braking functionality into a higher-level central control process. The inclusion of at least one external parameter, for example via industrially used / standardized communication protocols (e.g.based on the IEC 61131-9 standard or EC standard 61158) such as Modbus, IO-Link, EtherCAT, whether in the near field or beyond, also facilitates implementation in the context of industrial processes or corresponding controls / regulations and can facilitate the consideration of at least one (external) control / regulation variable, particularly in the context of full automation of manufacturing processes.

[0042] According to one embodiment, the setting of at least one magnetic operating state and / or at least one operating mode is implemented depending on the reaching or exceeding of at least one threshold value, in particular based on at least one threshold value from the following group: speed threshold value, torque or overload threshold value, time threshold value, slip or rotational position threshold value. This also enables or facilitates the implementation of further safety measures or further control / regulation specifications with a safety-relevant effect.

[0043] When slippage is referred to in the present disclosure, this also includes a predefined speed difference between the two driveline sections coupled by the MRF braking device. This speed difference can also be recorded as a parameter and evaluated in the context of generating control / regulation specifications, particularly in the context of slip monitoring. When coupling is referred to in the present disclosure, this also includes the ability of the MRF braking device to switch from a torque / load-free, leveled magnetic operating state to an operating state with braking effect (the braking effect caused by the MRF braking device establishes a certain type of coupling between the interacting driveline sections, e.g., depending on whether slip is permitted or not).Thus, when referring to certain braking characteristics, reference is also implicitly made to a certain way of coupling the interacting sections of the drive train, without, however, this being accompanied by coupling in the classic sense.

[0044] According to one embodiment, the MRF braking device is configured to provide a plurality of mutually graduated maximum applicable braking torques (plurality of mutually graduated nominal torques), namely at least a first and a second maximum applicable braking torque, wherein the MRF braking device is configured to select at least the first or the second of the plurality of maximum applicable braking torques depending on at least one parameter or at least one instantaneous parameter value for the instantaneous operating situation or for the instantaneous magnetic operating state or for a instantaneous operating mode and to define it as the maximum applicable (nominal) braking torque for a / the instantaneous operating mode. A graduated implementation can also be carried out, for example, depending on several predefinable speed ranges and thus, for example,Facilitate an optimized design with regard to the long service life of the MRF, and therefore also provides advantages of an implementation that can be adapted to application-specific criteria.

[0045] According to one embodiment, the MRF braking device is configured for a stepped nominal torque specification, in particular depending on at least one parameter or parameter value. This also facilitates an implementation that can be largely independent of structural or design-specific properties. In other words: It becomes easier to implement a standard MRF braking device for a wide variety of applications and power ranges without having to compromise on high safety standards. A stepwise, controlled / regulated specification for a maximum applicable braking torque also expands the application possibilities of the same type of MRF braking device for different applications, e.g., also with regard to a different type of implementation of slip and / or overload protection.

[0046] According to one exemplary embodiment, the MRF braking device is configured for drivetrain-specific overload protection and / or slippage, in particular by specifying at least one maximum applicable braking torque in a braking torque range below the rated torque of the MRF braking device, e.g., in a range up to 70% of the rated torque, in particular depending on at least one parameter or at least one instantaneous parameter value. Such a specification limiting the (instantaneous) load on the MRF braking device also provides advantages, in particular, with regard to safe continuous operation and advantageous long-term behavior, particularly with regard to the most constant properties of the MRF.When specifying the situation-specific maximum applicable braking torque, at least an MRF temperature value and / or a torque / speed range averaged over a previous operating period are advantageously taken into account.

[0047] For example, control / regulation takes place around at least one overload threshold value, in particular a controlled braking when the corresponding at least one overload threshold value is exceeded.

[0048] The control / regulation can be implemented, for example, using a microcontroller (µC)-based control / regulation unit, here simply (or synonymously) also referred to as µC. The µC enables highly dynamic control / regulation up to real-time applications. The µC can evaluate and further process data from internal and / or external sensors (particularly high-frequency sensors) and convert it into control / regulation specifications. The µC is advantageously connected to a potential-free (control) input (external voltage / current input), and the MRF braking device as such is advantageously fed or supplied with energy exclusively via the µC. A maintenance mode can be defined for the static operating situation or the de-energized (first) operating state.The µC is advantageously equipped with both analog and digital inputs and outputs, particularly for the purpose of high integration capability of the MRF braking system into different system types or processes.

[0049] It should be understood that the µC or the control / regulation unit can communicate with, or is designed accordingly, industrial-grade sensors via standardized communication interfaces / protocols (e.g., so-called Modbus or serial interface, IO-Ling, EtherCAT). The sensors can be native to the system or external to the system, e.g., part of existing system structures. Thus, the MRF braking system described here also delivers a very short response time combined with high control accuracy (highly dynamic, stable control, particularly with real-time functionality). Recorded or evaluated data can also be transferred, for example, via fieldbus infrastructures to a central system controller, e.g., in order to be able to generate individual control / regulation specifications more closely within the overall context of complex industrial processes.

[0050] According to one embodiment, the MRF region is geometrically and volumetrically predefined by axial sections of the MRF braking device that are axially fixed to one another by means of fastening means, wherein at least one of the axial sections, together with the rotor, defines at least one gap thickness of the MRF region, in particular both at least one radial gap thickness and at least one axial gap thickness. Such a structural design also provides advantages in particular with regard to the functional subdivision of the individual axial sections, as well as with regard to a slim design with reduced parts, and with regard to robustness, which can also facilitate scaling of the braking functionality and allow the complexity resulting from the use of MRF to be systematically well controlled.

[0051] According to one embodiment, the at least one PM, the coil, and the rotor are arranged in series in the axial direction, in particular without axial overlap. Such a structural design also provides advantages in particular with regard to a slim design, functional subdivision, efficient use of available space, and installation space optimization.

[0052] According to one embodiment, the coil extends radially outward at least approximately to the outer diameter of the rotor, and / or the coil extends radially inward at least approximately to the outer diameter of the PM. This relative positioning has proven advantageous, particularly with regard to the magnetic field that develops when the PM and EM fields overlap, especially with regard to magnetic / energetic efficiency.

[0053] According to one embodiment, the at least one PM and the coil are arranged in a first axial section of the MRF braking device, with the rotor being arranged in a second axial section of the MRF braking device, with the first and second axial sections being screwed together at the end faces, in particular abutting one another at least radially. This structural design also offers advantages in the overall context of the design of the MRF braking device, e.g., with regard to the definition / limitation of the MRF range.

[0054] According to one embodiment, the rotor is enclosed by three axial sections of the MRF braking device, which are fixed relative to one another in a predefined manner, in particular by screwing together, and thus predefine the geometry and size of the MRF region (and in particular also predefine the size of at least one gap thickness of the MRF region). This allows the individual axial sections to be designed based on comparatively simple and robust basic shapes, which offers advantages not least in the context of maintenance tasks, particularly regarding the MRF.

[0055] From a design perspective, advantageous embodiments can also be described as follows: The at least one permanent magnet is preferably arranged at least approximately at half the radius (halfway) of the radius of the outer surface of the rotor. The MRF region is preferably delimited at at least one location, in particular at least one radial position, by at least one MRF compensation unit (with respect to MRF pressure / volume changes), in particular comprising at least one first MRF compensation element in a first radial position and at least one second MRF compensation element in a second radial position, in particular with magnetic separation provided on the rotor between the first and second radial positions. The MRF compensation unit can, for example, be distributed over two axial sections of the MRF braking device, e.g.on the second axial section (for the rotor) and third axial section (for a cover or corresponding cover unit).

[0056] According to one embodiment, the MRF braking device comprises a control / regulation unit (preferably with a µC) or is communicatively connected thereto, which is in communication (wireless and / or wired) with a measuring unit comprising at least one sensor, in particular from the following group: rotary encoder, rotation / braking torque sensor, angular velocity sensor, rotational position sensor, temperature sensor, acceleration sensor, displacement / distance sensor; wherein the MRF braking device is configured to determine at least one parameter or at least one current parameter value based on current measured values ​​or historical measured values ​​already stored in a data memory of the control / regulation unit.This also favors a control / regulation implementation that is already autonomously functional, detached from any higher-level control / regulation processes, which can also improve the integrability of the MRF braking device into, for example, industrial processes.

[0057] It should be understood that the transmission paths referred to here can be configured either wirelessly and / or wired; the components connected to one another, e.g., for data communication, can optionally each have a communication module for wireless communication, e.g., based on a near-field communication protocol. Preferably, at least one control / regulation unit is equipped with a communication module configured for (communication) networks extending beyond the near field (e.g., NFC or LPWAN). Corresponding transmission paths are not explicitly depicted in the figures shown here.

[0058] According to one embodiment, the MRF braking device has a permanently installed temperature sensor that detects the MRF range. A system-specific temperature sensor for monitoring the MRF also facilitates the implementation of overload protection, especially in the context of a potential risk of overheating or at least with regard to excessive heating of the MRF, which may be detrimental to its service life. MRF temperature monitoring (capturing status information from the MRF braking device) also enables comparatively precise monitoring of the MRF's status and thus the load condition, particularly in the context of continuous load, which also allows for more targeted generation of control / regulation specifications, e.g.with regard to overload thresholds and / or slip and / or system-recommended rest phases, for example, for initiating measures such as slowing down drives / drive trains or even shutting down and / or activating an additional emergency braking unit. In this respect, temperature measurements also facilitate the initiation of a controlled / regulated transition from active braking operation, e.g., according to BZ3, to a passive state, e.g., according to BZ1 (thermal relief, optionally targeted or active cooling). Last but not least, temperature monitoring can also take into account the usually comparatively small effect of temperature on the viscosity of the MRF, which enables the actually transmitted torque to be adjusted even more precisely.

[0059] The aforementioned object is also achieved by a drivetrain arrangement comprising at least one MRF braking device according to the present disclosure. This results in the aforementioned advantages, in particular with regard to the safest possible operation of the drivetrain and one that is proactive or particularly prudent with regard to maintenance or fault diagnosis. The MRF braking device can perform at least one monitoring / monitoring function, including with respect to at least one (operating) parameter of the drivetrain. Optionally, the drivetrain arrangement also comprises a / the measuring unit. The drivetrain arrangement is advantageously equipped with a communication module for transmitting at least one parameter or measured value. The drivetrain arrangement can also be coupled to a central control device.

[0060] The aforementioned object is also achieved by implementation measures relating to a method for the controlled / regulated application of a braking torque, in particular by a computer program product comprising commands which, when the computer program product is executed on a computer or in a control / regulation unit, cause the computer to specify steps for controlling / regulating a method for the controlled / regulated application of a braking torque by means of an MRF braking device equipped with at least one permanent magnet, PM, with a geometrically and sized predefined MRF range, in particular in a drive train, according to the following steps: specifying a current operating mode, BM, of the MRF braking device based on one of at least three adjustable magnetic operating states, BZ, of the MRF braking device by controlled / regulated energization of at least one coil of the MRF braking device,Controlled / regulated leveling of a residual friction torque caused by the PM field by energizing, in particular by energizing the coil in opposite polarity, the coil for at least temporarily canceling the PM field for at least one operating situation, BS, detected in particular by the MRF braking device, by adjusting at least one magnetic operating state of the MRF braking device as a function of at least one parameter or at least one instantaneous parameter value, in particular during rotation of the drive train or from a minimum threshold value of a speed of the drive train and / or as a function of a rotational position parameter; in particular also when / through the use of an MRF braking device as described above. This results in the aforementioned advantages, in particular with regard to a very precise / adequate adjustment of the MRF braking device, depending on the situation and requirements.especially with high efficiency and high safety. Such a method can be implemented for the MRF braking systems described here, i.e., for MRF braking systems with a predefined MRF range in terms of size and geometry, without requiring adjustment of the size / geometry of the MRF range or a coupling function through an (axial) actuating movement acting on the MRF range.

[0061] In this case, it is advantageous to distinguish at least between the operating situation (possibly defined exclusively by external influences or specifications), the magnetic operating state, the operating mode, as well as the parameter(s), and the control / regulation specification(s). The respective parameter can be based, in particular, on a detected state or sensor value, and the respective control / regulation specification can be generated by the system, in particular in response to detected parameter values ​​and / or when predefined thresholds are exceeded.

[0062] In particular, a current operating mode of the MRF braking device is specified based on a first magnetic operating state with only a PM field (i.e., only residual friction torque), or based on a second magnetic operating state with a leveled residual friction torque (virtually no-load operation), or based on at least a third magnetic operating state with a predefined / predefinable braking torque with a predefined energized coil, in particular a first operating mode, a second operating mode, or a third operating mode, respectively. This also enables a particularly targeted adjustment of the (braking) characteristics of the MRF braking device, for example, in response to a pulse-like actuation or a non-standard load condition.

[0063] In other words: The MRF braking device or the correspondingly implemented method can be operated in a first, second and / or third operating mode (BM) and can, for example (for a specific application), be configured to output at least one first control / regulation specification in particular with regard to a target rotational position in the first operating mode (BM1) (e.g. based on a time parameter), and / or to output at least one second control / regulation specification in particular with regard to a time window or a point in time or a duration of an opposite-polar energization (e.g. based on a rotational speed parameter), and / or to output at least one third control / regulation specification in particular with regard to a current target magnetic field strength in the third operating mode (BM3) (e.g.based on a torque threshold and / or torque parameter), for example for the purpose of controlling a load absorption or braking effect around a torque threshold.

[0064] The control / regulation can generally be described as follows, starting from efficient current-based control (instead of voltage-signal-based control), particularly with regard to the analysis or evaluation of power curves and the resulting control / regulation of operating behavior: Generally speaking, position-dependent control / regulation specifications can be implemented, as well as torque-dependent and / or speed-dependent control / regulation specifications (each alternatively or in combination with or dependent on one another). Specifically, position-dependent control / regulation specifications enable or facilitate highly precise control of a braking torque, whereby motion states can be recorded / processed in real time, allowing the system behavior (or load absorption) to be dynamically adapted quickly and accordingly.Example: Processing process for a material web that is to be handled with a predefined tensile force. Special torque-dependent control / regulation specifications enable or facilitate highly precise, responsive, and application-specific clutch and braking behavior depending on the current load values. Special speed-dependent control / regulation specifications enable or facilitate continuous brake force control, particularly for the purpose of implementing protective functions and increasing efficiency.

[0065] In particular, the rotational position-dependent control / regulation favors advantageous implementations particularly in the following areas: test bench applications, safety / emergency braking functionality (e.g. at critical angular positions), reverse rotation protection and self-locking (e.g. in lifting systems, e.g. with regard to reversal points or rest phases), energy efficiency optimization (demand-based energy use, e.g. based on reduced braking effect in phases of low dynamics), wear minimization (particularly with regard to mechanical or thermal stress), cycle / process-controlled braking applications (e.g. in cyclically operating machines in the packaging industry).

[0066] In particular, torque-dependent control / regulation facilitates advantageous implementations, particularly in the following areas: overload functionality / protection (e.g., by automatically increasing the braking force when limit values ​​are exceeded), adaptive braking during load changes (particularly thanks to the large operating range of the MRF brake), mapping / simulation of real load scenarios (particularly thanks to high precision and stepless control behavior), smooth starting / stopping, particularly thanks to stepless braking force adjustment.

[0067] In particular, speed-dependent control / regulation facilitates advantageous implementations, particularly in the following areas: speed adjustment / reduction for particularly fast systems (controlled braking without load peaks), gentle braking at particularly high speeds (flywheels, centrifuges), overspeed protection functionality, optimization of starting / starting processes (e.g. with rotating masses), particularly for the purpose of improved process control, dynamic control in test bench operation, e.g. with regard to acceleration or deceleration processes.

[0068] The applications described here illustrate a whole range of advantages that can be advantageously realized in drivetrains based on the present invention, especially thanks to MRF technology. This is particularly due to fast response times and low wear, but primarily due to application-specific, particularly precise control / regulation specifications, and not least due to the possibility of reducing technical complexity: The generation or application of the braking force is advantageously achieved via current control, whereby rapid analysis of sensor data enables immediate adjustment of the clutch / brake behavior. Recurring operating situations or behavior patterns can also be evaluated.

[0069] Thus, the following control / regulation parameters can also be conveniently implemented in the context of the applications described here, for example to specify a predefined torque amount (or a predefined magnetic field strength) depending on a current rotational position: i) temperature of coil and / or MRF; ii) speed; iii) viscosity of the MRF; (iv) predefined thresholds, in particular with regard to at least one overload limit; v) current rotational position;

[0070] In this respect, a microcontroller (µC)-based control unit (microcontroller-based control / regulation controller, microcontroller-based control / regulation unit) can provide the control / regulation for at least one of the three magnetic operating states, in particular in the form of a dynamic application, in particular for the energized state BZ3, BM3, advantageously current-based, in particular for specifying the instantaneous strength of the magnetic field and / or for monitoring at least one overload threshold value, in particular taking into account at least one instantaneous temperature and / or torque and / or rotational position parameter.

[0071] Such control / regulation proves to be particularly advantageous in drive trains that are continuously loaded at comparatively high speeds, especially since it allows for the implementation of improved safety measures and / or the operating behavior of the drive train to be actively and positively influenced. The control / regulation can, for example, be implemented when a maximum temperature for the MRF (e.g. 100°C) is reached during BZ3 in the BM3 in such a way that the speed is regulated and / or that a (sliding) upper torque threshold is reduced in a predefined manner. A rotational position-specific control can also be provided, particularly in the case of comparatively slow-running drive trains, for example a rotational position-dependent increase / decrease in the applied braking torque. This type of implementation is, for example,also conceivable for drive trains of wind turbines, in which the rotor blades may generate (resonance) vibrations in certain rotational positions, in particular with the effect that the measures described here can minimize or contain the risk of resonance vibrations.

[0072] The control / regulation unit can advantageously be powered by an external power / voltage supply, thereby controlling the MRF braking device directly and with low losses, thus eliminating the need for additional switching elements. This also minimizes potential time delays and potential parasitic effects on the signal path or during data transmission. A potential-free (control) input also facilitates easy integration into higher-level control systems (e.g., process control, industrial control). This also allows for easy external activation / deactivation.

[0073] For example, the following implementation is provided, where the suffix "a" for the respective parameter or the respective control / regulation specification indicates a static, non-rotating, here referred to as "static" operating situation (BS1) of the drive train, and the suffix "b" indicates a rotating or here referred to as "dynamic" operating situation (BS2), with the following columns in the following table: Operating situation, operating state, operating mode, parameter, control / regulation specification BS1(static) BZ1 (PM field only) BM1 (EM without power) P, P1a SR1, SR1a BZ2 (leveled) BM2 (EM opposite pole) P, P2a SR2, SR2a BZ3 (PM+EM) BM3 (EM powered) P, P3a SR3, SR3a

[0074] For BZ1 (residual torque only), only the PM field is present (be it in BS1 or BS2), thanks to which sedimentation can be prevented, whereby the effect of the MRF is so low that it can only be described as a passive (barely noticeable, not significantly relevant for the respective drive train) torque. This condition can also be advantageously used for maintenance purposes. As parameter P, P1a in the static operating situation BS1 for BZ1, for example, a rotation angle parameter (rotational position parameter) and / or a time and / or a temperature parameter can be implemented. As control / regulation specification SR1, SR1a in the static operating situation BS1, for example, a reactivation of operation (e.g. after a technically provided cooling / rest phase) and / or a temporary change of the current (resting) rotation position (particularly for the purpose of optimizing sedimentation-inhibiting measures) can be implemented.There is not necessarily only one BM1, or different operating modes can also be implemented for BZ1.

[0075] For BZ2 (leveled), leveling is achieved by the EM field thanks to the opposite polarity of the current, so that no force / torque transmission occurs at all. For example, in applications where a start-up / run-up process is frequently initiated, where the residual friction / braking torque should be as low as possible, this operating state may be advantageous. Maintenance or troubleshooting in manufacturing processes can also be carried out in the second operating state, particularly since a shaft enclosed by the MRF braking device can be rotated forwards and / or backwards without torque (particularly improving operability), e.g. for changing input material or semi-finished products or the like. The present invention therefore also promotes minimizing plant downtimes. The parameter P, P2a in the static operating situation BS1 for BZ2 can be, for example,A rotation parameter (yes / no), a rotation angle parameter (rotational position parameter), and / or a time and / or temperature parameter can be implemented (a cooling phase can also be bridged by adjusting BZ2). An energy-saving measure can be implemented as the control / regulation specification SR, SR2a in the static operating situation BS1, e.g., by switching back to the non-energized BZ1 when a certain speed threshold is undershot and / or a time threshold is exceeded. There is not necessarily only a single BM2, and different operating modes can also be implemented for BZ2.

[0076] For BZ2 at BS1, it should be explained that even when the drive train is at a standstill, it can be expedient to energize the coil at least temporarily or in short, selected time windows (opposite or same pole), especially to more effectively counteract sedimentation or an inhomogeneous particle distribution. The corresponding control / regulation command SR2a may be issued within / at tight time constraints.

[0077] For BZ3 (braking torque, especially actively controlled), the control / regulation described here is of particular use, especially since it allows the essential operating behavior for the operation of the corresponding drive train to be specified, e.g., also with regard to overload protection and slippage, particularly thanks to rapid dynamic adaptation of the braking / clutching properties generated by the MRF braking device. This also applies to the static BS1, e.g., when a holding function is to be ensured by the MRF braking device. For example, a rotation parameter (rotation yes / no), a rotation angle parameter (rotational position parameter), and / or a time and / or temperature parameter can be implemented as the parameter P, P3a in the static operating situation BS1 for BZ3. For example, the type of current supply to at least one coil can be implemented as the control / regulation specification SR, SR3a in the static operating situation BS1 (e.g.,for a holding function), e.g., based on a current curve. It goes without saying that BM3 in BZ3 can be specified for specific applications, e.g., to control / regulate the strength of the magnetic field with respect to at least one parameter.

[0078] It should be understood that the slip functionality described here may require more frequent switching between BS1 and BS2, so that, for example, a speed (difference) parameter can also be implemented for BS1. At least one external parameter can also be implemented, not only in the context of a / the slip functionality.

[0079] For the dynamic operating situation BS2, for example, the following implementation can be provided, whereby in comparison to the static operating situation BS1, at least one further parameter (P4) or at least one further control / regulation specification SR4 can be implemented, in particular at least one threshold value, for example relating to a speed parameter, in particular for the purpose of implementing at least one safety function, for example in the case of permanently loaded drive trains, for example specified by external processes with narrow parameter specifications: BS2(dynamic) BZ1 (PM field only) BM1 (EM without power) P, P1b SR1, SR1b BZ2 (leveled) BM2 (EM opposite pole) P, P2b SR2, SR2b BZ3 (PM+EM) BM3 (EM powered) P, P3b SR3, SR3b BZ3 (PM+EM) BM3 (EM powered) P, P4 SR4

[0080] Advantageously, at least one speed-based parameter, at least one torque-based parameter, at least one rotational position-based parameter and / or at least one external parameter can be implemented as parameters. As control / regulation specification SR1b in dynamic operating situation BS2 for BZ1, for example, a change to BZ2 or BZ3 can be implemented, e.g. based on a time and / or speed and / or rotational position parameter. As control / regulation specification SR2b for BZ2, for example, a change to BZ1 or BZ3 can be implemented, e.g. based on a time and / or speed and / or temperature parameter (upper threshold value not to be exceeded). As control / regulation specification SR3b for BZ3, for example, a torque and / or speed control / regulation can be implemented, e.g. based on a speed and / or temperature parameter (upper threshold value not to be exceeded).As a control / regulation specification SR4, for example, a torque control based on at least one external parameter can be implemented, e.g. concerning a target torque or a target force of an industrial processing process, in particular with BM3 specifically set depending on the P4.

[0081] The respective control / regulation specification (be it for BS1 or for BS2) can also include at least one signal generation / transmission function and / or warning function.

[0082] In particular, the respective manner of operation of the MRF braking device can be based on at least two different operating situations, at least three different magnetic operating states, at least three different operating modes, in particular depending on at least four parameters, in particular when implementing at least four different control / regulation specifications.

[0083] For the respective parameters P, P1,..., P4, corresponding threshold values ​​SW, SW1, ..., SW4 can be predefined, in particular specifically for the respective BS, BZ and / or BM.

[0084] It should be understood that the operating situation of the drive train can be defined not only with regard to the rotation of the shaft enclosed by the MRF braking device, but also, for example, depending on whether the drive train itself is spatially relocated, e.g., if it is a drive train implemented in a mobile device or a vehicle. For the sake of simplicity, reference is made here to the operating situation described here as the second operating situation, although a different situation with regard to sedimentation may exist depending on the type and duration of the movement or vibration of the MRF braking device associated with the mobile relocation. In this respect, the group of evaluable and implementable parameters can also include at least one external parameter (P ext) in particular concerning the ambient situation or the installation situation of the drive train and / or at least one measured value or control / regulation variable of a processing process.

[0085] For example, a braking effect is controlled / regulated by at least a speed-dependent manner of energizing the coil by specifying a magnetic operating state of the MRF braking device from the following group: first magnetic operating state with exclusively PM field (in particular with friction losses in the lower single-digit percentage range of the nominal torque), second magnetic operating state with leveled residual friction torque (in particular significantly below 1% of the nominal torque), at least a third magnetic operating state with predefined / predefinable braking torque with controlled / regulated predefined energization of the coil (e.g. braking torque in the range of 100 to 200 Nm).

[0086] It should be understood that control with regard to either a backlash-free or leveled operating state with a compensating electromagnetic counter-signal to the PM can be implemented in a comparatively simple manner. Overall, this results in great variability with regard to the specifiable control / switching behavior (e.g., particularly smooth start-up, drivetrain-specific shutdown, braking) and with regard to the feasible control / regulation scenarios, in particular for the purpose of the finest possible adjustment of transitions between different operating situations (internal, external). Accordingly, the present invention also facilitates the replacement, exchange, and / or expansion of conventional mechanical systems, or a functional expansion of these, or even an extension of the service life / operating time through a comparatively small retrofitting measure using at least one of the MRF braking systems described here.

[0087] It has been shown that a control / regulation can be implemented in particular based on at least one of the following parameters for generating control / regulation specifications for setting at least one operating mode: i) first temperature parameter relating to a current temperature of the coil or of the at least one EM, in particular for the purpose of controlling / regulating the torque; (ii) speed parameters relating to an instantaneous speed, possibly in combination with or depending on the viscosity of the MRF; iii) second temperature parameter concerning an instantaneous temperature of the MRF; iv) at least one magnetic field parameter relating to the instantaneous magnetic field or the magnetic field strength; v) at least one torque parameter relating to an instantaneous torque absorption, in particular with respect to at least one overload threshold value; vi) at least one rotational position parameter relating to a current rotational position about the rotation axis, in particular for the purpose of specifying a rotational position-dependent braking effect, e.g. in comparatively slowly rotating or slowly further rotating applications; vii) at least one time parameter, in particular relating to a period of time since the last rotation, i.e., relating to standstill time, in particular for the purpose of active rotation or change of the rotational position, e.g. to improve a sedimentation inhibition effect;

[0088] It is to be understood that a control / regulation is advantageously implemented as a current-based control / regulation, in particular with regard to efficiency maximization, i.e. it can be designed largely or completely independent of voltage measurement values, in particular as a constant current control.

[0089] In the embodiments described below, reference is also made to a computer program product with corresponding implementation.

[0090] According to one embodiment, at least one of the magnetic operating states, in particular the first magnetic operating state and / or the second magnetic operating state, is further specified in terms of control / regulation technology as a function of at least one time parameter, in particular when a predetermined maximum duration is exceeded, in particular when no rotation is present. This also promotes particularly reliable implementation, e.g., with regard to sedimentation inhibition.

[0091] It should be understood that the first and second magnetic operating states are advantageously specified as a function of a rotary operating situation and also as a function of a time parameter, in particular on the one hand with regard to preventive magnetic field measures with regard to sedimentation and with regard to (idling) operation with as little friction as possible, but on the other hand also in terms of energy. Thus, energizing the EM (or the coil) may be dispensable, in particular, if at least essentially load-free operation is not required at all (e.g., detected based on a braking effect requirement parameter), or if a certain sedimentation time threshold is reached; the type and manner of energization for the second magnetic operating state can also be specified as a function of time and / or speed and / or braking effect requirement, in particular gradually, e.g.with regard to the minimum possible current draw depending on a rotation-related MRF mixing degree; advantageously, it is therefore possible to actively switch to both the first magnetic operating state and the second magnetic operating state, or to switch back and forth between them (control or regulation loop, in particular with regard to steps S21, S22 described here).

[0092] The present invention therefore also enables implementations in which the at least one PM is / will be dimensioned in such a way (i.e., with a comparatively large PM magnetic force) that a certain level of friction can be ensured (if desired). Even for such configurations, the present invention enables safe and, in particular, energy-efficient operation.

[0093] According to one embodiment, a residual friction torque caused by the PM field is leveled off by applying current to the coil in opposite polarity, in particular below 1% of the nominal torque, in particular below 1 Nm. In addition to the numerous different operating modes described here, this also enables friction-minimized, essentially load-free rotation or holding the MRF braking device without noticeable holding force or without a clutch function, which can be useful, for example, for frequently recurring starting processes.

[0094] According to one embodiment, on the one hand, the magnetic operating state is predetermined by control / regulation technology at least as a function of a current rotation, while on the other hand, the current operating mode of the MRF braking device, in particular for the at least one third magnetic operating state, is also predetermined by control / regulation technology, in particular based on at least one parameter from the following group: speed-based parameter, torque-based parameter, rotational position-based parameter, external parameter. This also facilitates, for example, a very drive train-specific setting of technically difficult, individual, situation-dependent starting and / or braking or stopping processes, for example in the context of an emergency stop (e.g., a safety function in the event of a power supply failure in the sense of a controlled / regulated stopping of an industrial process or the like that protects the mechanical components).

[0095] Advantageously, the control / regulation is implemented as a function of at least one temperature parameter, in particular as a function of an application-specific temperature threshold, which is / is included in addition to the otherwise underlying control / regulation variables. This provides a high degree of safety, both for the process as such and for the MRF braking device itself. An overload protection device can, for example, be implemented in such a way that the MRF braking device is switched to the leveled operating state or to the de-energized operating state with only the PM field. Optionally, a downstream emergency brake can also be provided in the corresponding drive train. For example, when a pre-definable threshold is reached / exceeded, a warning signal can also be generated, which, for example,can be transmitted via the control / regulation unit or via a separate communication module, e.g., to indicate an existing or potentially imminent overload condition. Advantageously, at least one temperature threshold is implemented for this purpose, optionally depending on other parameter values ​​(e.g., torque, speed).

[0096] According to one embodiment, at least one operating mode in at least one magnetic operating state of the MRF braking device is set as a function of at least one parameter or at least one current parameter value such that the MRF braking device is operated according to a stepped nominal torque specification based on at least two overload thresholds. This also enables overload protection to be implemented in a particularly targeted, drivetrain-specific manner.

[0097] According to one embodiment, at least one operating mode in at least one magnetic operating state of the MRF braking device is set as a function of at least one parameter or at least one current parameter value such that the MRF braking device is operated according to a predefined range of a speed difference corresponding to a predefined slip or with respect to at least one threshold value relating to a maximum deviation from the predefined slip. On the one hand, this can facilitate a functional expansion by at least one safety function, and on the other hand, the range of variation of the adjustable operating modes can be specified over an even wider spectrum. For example, the implementation is based on a speed and / or torque and / or rotational position parameter.

[0098] At this point, one of the possible implementations for the application case of an installation situation in a processing line (system) for the mechanical processing of a material web (particularly paper or textile industry) is described as an example, in which the material web is to be handled as far as possible within a narrow window of tensile force (keyword web tension control), whereby the tensile force is specified via a drive train in which at least one of the MRF braking devices described here can be installed: When unwinding large rolls of material such as paper or textile webs, large inertial forces are at work, often with high drive / feed speeds, but at the same time it must be possible to maintain the web tension as precisely as possible within a narrowly predefined value range. Such material webs can, for example,also be inhomogeneous in their material properties or particularly sensitive to temperature, so that a situation-dependent adaptation of the process is beneficial. Until now, mechanical units such as so-called dancer systems were often installed. The present invention, however, favors the omission of such systems in favor of active control / regulation by means of the MRF braking device described here, wherein at least the tensile force or a torque is evaluated as an external input parameter, wherein the MRF braking device is controlled / regulated, particularly in the BZ3, in such a way that the force generated in the MRF specifies the resulting braking torque in such a way that the tensile force or web tension remains in the predefined value range, even under changing process conditions. Optionally, e.g.A rotation angle sensor can be implemented, in particular for the purpose of compensating for slippage, blockages, standstill, overload protection, avoiding uncontrolled movements or resonance (or unfavorable vibration ranges / frequencies), or the like. The detected / generated speed signal also simplifies synchronization with other processes and promotes process integration. The present invention also enables comparatively fast and precise control / regulation of the external parameter (here the tractive force) in such a context, in particular through correspondingly fast control / regulation specifications for the speed or torque applied to or set with the MRF braking device, in particular thanks to low latency and high control accuracy. In this way, a very precise and fast specification of a predefined torque orA predefined braking force can be ensured, and at the same time, one or more threshold values, e.g., regarding an (internal / external) overload and / or a slip amount that must not be exceeded, can be taken into account in the control / regulation process. Last but not least, a protective function can be easily implemented for the system, process, or material web on the one hand, and for the MRF braking device on the other, particularly based on multiple threshold levels (internal, external).

[0099] The aforementioned object is also achieved by a computer program product comprising instructions which, when the computer program product is executed on a computer or in a control / regulation unit, cause the computer to carry out steps for controlling / regulating a method according to the present disclosure on the computer or in / by means of the control / regulation unit, in particular a computer program product configured to specify a current operating mode, BM, of a / the MRF braking device with a predefined MRF range by controlled / regulated setting of at least one magnetic operating state, BZ, of the MRF braking device as a function of at least one parameter, in particular as a function of a rotating operating situation when the braking effect is not called up and a non-rotating operating situation when the braking effect is not called up;in particular for controlling / regulating an MRF braking system according to the present disclosure. Based on the aforementioned advantages, this also facilitates application-specific optimization, for example, by adapting a corresponding control / regulation unit specifically for each drive train, e.g., with respect to at least one parameter threshold value.

[0100] The above-mentioned object is also achieved by using three axial sections that can be fixed axially to one another for the geometric and volumetric definition and delimitation of an MRF region of an MRF braking device with a permanent magnet, PM, that can be set in at least three magnetic operating states, BZ, in particular in or for a drive train, for providing the MRF braking device with electromagnetically leveled residual friction torque in a rotating operating situation when the braking effect is not called up and for providing the MRF braking device with a PM field, in particular in a non-rotating operating situation when the braking effect is not called up and for providing the MRF braking device with a PM field and a magnetically equivalent EM field, in particular in a rotating operating situation when the braking effect is called up,The EM field for applying the braking effect is generated depending on at least one parameter from the following group: time parameters, in particular relating to a maximum period without rotation, rotational state parameters and speed parameters, acceleration parameters, temperature parameters, braking effect requirement parameters, rate of change parameters relating to at least one of the parameters (in particular the speed), torque parameters, rotational position parameters; in particular in an MRF braking device according to the present disclosure. This allows the aforementioned advantages to be realized, in particular with regard to a particularly robust, simple, easily scalable (structural) design that can be used as a basis for application-specific adaptations.

[0101] The aforementioned object is also achieved by using a control / regulation unit for specifying the type and manner of energization of at least one coil of an MRF braking device with a permanent magnet, PM, and a geometrically and volumetrically predefined MRF range for specifying a / the current operating mode, BM, of the MRF braking device, in particular depending on both a current operating situation, BS, and at least one / the third magnetic operating state of the MRF braking device, in which a / the PM field and, with the same magnetic effect, an / the EM field are applied to the magnetorheological fluid, MRF, wherein the type and manner of energization is generated depending on at least one parameter from the following group: time parameters, in particular relating to a maximum duration without rotation, rotation state parameters and speed parameters, acceleration parameters, temperature parameters, braking effect requirement parameters,Rate of change parameters relating to at least one of the parameters (in particular the rotational speed), torque parameters, and rotational position parameters; wherein, depending on a change from an operating situation without rotation to an operating situation with rotation, the system automatically switches from the first to the second magnetic operating state if a braking effect is not requested, and automatically switches from the first to the third magnetic operating state if a braking effect is requested; in particular in an MRF braking device according to the present disclosure. This allows the aforementioned advantages to be realized, in particular with regard to a comparatively streamlined manner of implementing and integrating additional functionality.

[0102] The aforementioned object is also achieved by using an MRF braking device according to the present disclosure in an industrial (processing) process to maintain at least one external parameter relating to a control variable of the industrial process, e.g., an industrially applied predefined tensile force or a predefined range of this tensile force, or an industrially applied predefined torque or a predefined range of this torque. This allows the aforementioned advantages to be realized, particularly with regard to advantageously simple integration into (industrial) processes.

[0103] The aforementioned object is also achieved by using an MRF braking device according to the present disclosure in a drive train for maintaining at least one external parameter relating to a control / regulating variable for the operation of the drive train, e.g., a predefined torque applied by the drive system or a predefined range of this torque, or a speed maintained by the drive system or a predefined range of this speed. This allows the aforementioned advantages to be realized, in particular with regard to advantageously simple functional expansion or integration, e.g., of a safety-related measure in possibly very old, e.g., essentially mechanically functioning existing systems.

[0104] It is understood that, based on the present disclosure, a person skilled in the art can conduct investigations and further developments to optimize the operating behavior of the MRF brake system described here, in particular also experimental investigations and / or modeling and simulation specifically concerning load conditions, force and torque transmission, sedimentation behavior, starting behavior, and long-term magnetic behavior. In doing so, a person skilled in the art can also use common methods for computer-aided generation of options for action and / or computer-aided identification of optimization potential. Specifically within the scope of the present invention, a person skilled in the art is considered to be an engineer with several years of professional experience in the field of MRF brake design.

[0105] Summary: Braking systems based on magnetorheological fluids (MRF) present challenges in finding a good compromise, particularly between the following requirements: structural complexity, number of components, required volume of MRF, maximized braking effect, friction minimization, maximized service life, minimized installation space requirements, reliability even during longer downtimes. According to the invention, an MRF braking system is provided for applying a braking torque by means of magnetorheological fluid MRF, in particular in a drive train, comprising a rotor, in particular a T-shaped rotor with magnetic separation, comprising a coil and at least one permanent magnet (PM) implemented to inhibit sedimentation, wherein the rotor is mounted in a chamber filled with MRF which is geometrically and dimensional orrotates in a volumetrically predefined MRF region with at least one predefined gap thickness, wherein the coil and the at least one permanent magnet are arranged relative to one another in such a way that a minimum cross-sectional area is ensured for forming a closed magnetic circuit caused at least by the coil, optionally superimposed by the PM field, wherein the MRF braking device is configured to apply a braking torque by energizing the coil; wherein the MRF braking device is configured to level out a residual friction torque caused by the PM field by energizing the coil, in particular by energizing it in opposite polarity, in a controlled / regulated manner, for at least temporarily canceling the PM field, in particular during rotation. The invention further relates to implementation measures for a corresponding braking torque application method and a corresponding control / regulation system.In this way, an advantageous type of operating behavior can be ensured, in particular with regard to at least three different magnetic operating states. SHORT DESCRIPTION OF THE CHARACTERS

[0106] The invention is described in more detail in the following drawing figures. Reference numbers not explicitly described in a particular drawing figure refer to the other drawing figures. They show: Fig. 1 shows a schematic representation of a MRF braking device according to an exemplary embodiment in a drive train arrangement with the rotor of the MRF braking device in a rotationally fixed connection on a shaft of the drive train in a half-sectioned side view; Fig.2 shows a schematic representation of an MRF braking device according to embodiments in a half-sectioned side view, wherein control / regulation aspects are highlighted or illustrated; Fig. 3 shows a schematic representation of steps of a method for which or in the context of which the present invention can be implemented according to embodiments; DETAILED DESCRIPTION OF THE FIGURES

[0107] The invention will first be explained with general reference to all reference symbols and figures. Special features or individual aspects of the present invention, or aspects that are clearly visible / depictable in the respective figure, will be addressed individually in connection with the respective figure.

[0108] Provided is an MRF braking device 10 configured to apply a braking torque M10 by means of magnetorheological fluid 3, MRF, in particular in a drive train, comprising a rotor 12, in particular a T-shaped rotor with magnetic separation 12.1, comprising a coil 13 (or, analogously, an electromagnet, EM) and at least one permanent magnet 14, PM implemented to inhibit sedimentation, wherein the rotor 12 rotates in a geometrically and volumetrically predefined MRF region 15 filled with MRF 3, wherein the coil 13 and the at least one PM 14 are arranged relative to one another in such a way that a minimum cross-sectional area A1 is ensured for forming a / the closed magnetic circuit caused by the coil 13, wherein the MRF braking device 10 is configured to apply a / the braking torque by energizing the coil 13;wherein the MRF braking device 10 is configured to level a residual friction torque M3 caused by the PM field by energizing, in particular by energizing the coil 13 in a controlled / regulated manner for at least temporarily canceling the PM field for at least one operating situation, BS, detected in particular by means of the MRF braking device, by setting at least one magnetic operating state, BZ, of the MRF braking device 10 as a function of at least one parameter P or at least one instantaneous parameter value;

[0109] Furthermore, at least one implementation measure is provided for realizing a method for the controlled / regulated application of a braking torque by means of an MRF braking device 10 equipped with at least one permanent magnet 14, PM, with a geometrically and sized predefined MRF range 15, in particular in a drive train, wherein a current operating mode, BM, of the MRF braking device 10 is predetermined based on one of at least three adjustable magnetic operating states, BZ, of the MRF braking device 10 by controlled / regulated energization of at least one coil 13 of the MRF braking device 10, wherein a residual friction torque caused by the PM field is leveled in a controlled / regulated manner by energizing, in particular by energizing the coil 13 in opposite polarity, for at least temporary cancellation of the PM field for at least one operating situation, BS, detected in particular by the MRF braking device 10.by setting at least one magnetic operating state, BZ, of the MRF braking device 10 as a function of at least one parameter P or at least one instantaneous parameter value.

[0110] The drive train 1 is, in particular, a drive technology drive train. The drive train 1 can, for example, be operated in or for an industrial process, or be part of a system, e.g., a wind turbine, or be part of a machine or a vehicle. The shaft 2 or similar torque-transmitting drive train component can be adapted to the application-specific requirements and is therefore not limited to specific dimensions or torque ranges or similar boundary conditions. The same applies to the bearings 7 (one or more) and / or seals 9 (one or more) involved. A person skilled in the art can specify such standardized machine elements based on the present disclosure and with regard to specific application conditions, based on empirical values ​​regarding type, size, service life, and similar properties.The connection 5 between the rotor and shaft can, in particular, be designed as a rotationally fixed, positive and / or non-positive connection. In this respect, too, application-specific features can be taken into account in the design. The stator 11 can also be designed with regard to design details based on empirical values ​​and previously known configurations, in particular in the field of tension between application-specific loads or specifications. From a macroscopic perspective, the design can, for example, be subdivided into three sections, which can be reversibly assembled to one another, for example, using fastening means 19 (preferably positive / non-positive, e.g., screw connections): first axial section 10.1, in particular the coil and PM section; second axial section 10.2, in particular the rotor section; third axial section 10.3, in particular the cover unit. The stator is advantageously formed by the second axial section 10.2, in a rotationally fixed assembly / installation situation at the first and third axial sections. These three axial sections advantageously jointly define the MRF-filled region 15 (MRF region), and in combination with the arrangement and design of the rotor, also the at least one gap 15.1 with the at least one predefined gap thickness d15.

[0111] The magnetorheological fluid 3, MRF, which is advantageously used / usable for the MRF braking device 10 described here can, for example, have or comprise the following components: carbonyl iron powder, carrier fluid / liquid, dispersant, sedimentation-inhibiting component, wear- / oxidation-inhibiting component.

[0112] It is worth mentioning that the rotor 12 is advantageously T-shaped, preferably with a magnetic separation 12.1 in the transition area between the radial section and the axial T-section. It has been shown that this can advantageously influence the magnetic properties and thus the efficiency of the entire MRF braking system. The magnetic separation can be achieved, for example, by varying the material, particularly by using non-magnetic material.

[0113] Advantageously, at least one MRF compensation unit 17 (with regard to pressure / volume changes in the MRF range) is installed, in particular comprising at least one first MRF compensation element 17.1 (in particular closed-cell foam, in particular FKM foam, fluororubber foam), at least one second MRF compensation element 17.2 (for example, both provided radially comparatively far inward in the second axial section 10.2), at least one third MRF compensation element 17.3 (for example, provided radially comparatively far outward in the third axial section 10.3).

[0114] A drive train arrangement 20 comprising at least one such MRF braking device 10 is installed, for example, in a drive technology application or in an industrial process.

[0115] The MRF braking device 10 or the drive train can be equipped with a measuring unit 18, in particular with a measuring unit comprising at least one sensor, in particular from the following group: rotary encoder, rotation / braking torque sensor, angular velocity sensor, rotational position sensor, temperature sensor, acceleration sensor, path / distance sensor (e.g., laser). Optionally, several of these sensor types are provided in groups or in combination with one another. Independently of this, the MRF braking device 10 advantageously has at least one permanently installed temperature sensor 18.1. Incidentally, the position of the Fig.1 can be varied, in particular in such a way that the temperature sensor is arranged as far radially outward as possible, in particular in a region of high relative speeds or relatively particularly high circumferential speeds, and in particular also in a region with minimized risk with regard to any air inclusions present in the MRF.

[0116] A control / regulation unit 30 (in particular with a communications module and data storage device) is in electrical / data contact via at least one line 31, in particular by implementing the electrical power supply or electrical connection of the MRF braking device via the connection of the control / regulation unit. The control / regulation unit 30 can comprise a communications functionality; optionally, a (separate) communications module 32, in particular with implemented warning functionality, is provided. The (data) communication takes place, for example (among other things), via at least one connection to at least one database 40, for example a database configured as a wirelessly accessible server component.

[0117] It is to be understood that the components described here are arranged relative to each other in such a way that a / the minimum cross-sectional area A1 or a corresponding cross-sectional area ( Fig.1) to form a closed magnetic circuit does not fall below a constructively predeterminable minimum threshold value, in particular in order to be able to keep the magnetic flux density or the magnetic properties in a favorable range even with a superimposed PM / EM field.

[0118] In particular, an arrangement in which the at least one PM (or its central longitudinal axis) is arranged at least approximately at half the radius r1 of the radius r2 of the outer surface of the rotor has proven advantageous in several respects. The coil or the at least one EM can extend in the radial region between r1 and r2, optionally also over a comparatively large portion of this region, e.g., over 75% up to r2.

[0119] In the implementation of the present invention, a distinction is made, on the one hand, with regard to a current operating situation BS, in particular with regard to the first operating situation BS1 (static) and the second BS2 (dynamic), and, on the other hand, with regard to the magnetic operating state BZ, in particular with regard to the first magnetic operating state BZ1 (only PM field, currentless), the second magnetic operating state BZ2 (minimized residual friction torque thanks to a leveled PM field due to a superimposed, oppositely polarized EM field), and the third magnetic operating state BZ3 (superimposed EM and PM fields for the purpose of a predefined / predefinable braking effect). Operating modes BM can be specified situation- / state-specifically via control / regulation specifications SR, in particular at least one first operating mode BM1, at least one second operating mode BM2, and at least one third operating mode BM3.For example, at least three or four different control / regulation specifications SR are implemented for the static BS1 and the dynamic BS2, in particular at least three control / regulation specifications SR1a, SR2a, SR3a for the static BS1 (in particular reactivation of operation, temporary change of the current rotational position, energy saving measure, type of current supply) and at least four control / regulation specifications SR1b, SR2b, SR3b, SR4 for the dynamic BS2 (in particular change to another BZ, torque and / or speed control / regulation, torque control based on at least one external parameter).

[0120] For example, at least three or four different threshold values ​​are implemented, in particular at least one speed threshold value SW1, at least one torque or overload threshold value SW2, at least one time threshold value SW3, and / or at least one slip or rotational position threshold value SW4.

[0121] As parameter P relating to the MRF braking device, for example, a first parameter P1 (e.g. speed-based parameter), a second parameter P2 (e.g. torque-based parameter), a third parameter P3 (e.g. rotational position-based parameter), a fourth parameter P4 (e.g. time parameter and / or temperature parameter) can be implemented, in particular in combination with a temperature threshold value SW, for example also in combination with an external parameter Pext, for example relating to environmental influences and / or installation situation and / or at least one external control / regulating variable such as a tensile force in a processing process for material webs.

[0122] The method described here for the controlled / regulated application of a braking torque by means of an MRF braking device 10 equipped with at least one permanent magnet 14, PM, with a geometrically and sized predefined MRF area 15 can comprise, for example, the following steps: Step of detecting or at least processing S1 at least one measured value, in particular comprising a rotation measured value and / or comparing at least one parameter, in particular a time parameter, wherein step S1 can also comprise the recognition of the operating situation (static, dynamic), e.g. based on a rotational position or a rotation; Step of setting S2 the desired magnetic operating state (BZ) among / from at least three magnetic operating states; Step S21 of suspending energization of the coil (only PM field is present) to set the first magnetic operating state BZ1; Step of counter-polar energization S22 of the coil for the purpose of leveling a / the PM field, for setting the second magnetic operating state BZ2; Step of energizing the coil S23 to superimpose the PM and EM fields to generate a predefined braking effect, to set the desired third magnetic operating state BZ3 or the corresponding operating mode BM; Step of setting S3 of the operating mode (BM), in particular for BZ3, in particular depending on a current load / operating situation of the drive train and / or e.g. depending on threshold values, time parameters, speed / rotational position parameters, external parameters, in particular comprising the step of energizing the coil S33 within BZ3 to specify a specific BM3; Step of specifying a control / regulation measure S4, in particular concerning the corresponding operating mode, in particular concerning the type of EM field generated, and / or concerning the generation of a signal; Step of specifying or adjusting S4a the magnetic field generated by the EM; step of generating / transmitting S5 a signal, e.g., a warning signal or corresponding data, e.g., in the event of an impending overload situation and / or high temperatures or similar predefined limit values.

[0123] In the following, special features of the invention are explained with reference to individual figures or at least one embodiment.

[0124] In Fig.Figure 1 shows a structural design of an MRF braking device 10 consisting essentially of three axial sections 10.1, 10.2, 10.3 fixed to one another, wherein the three axial sections delimit the MRF area 15 and define it geometrically and volumetrically. Coil 13 and PM 14 are arranged relative to one another and also relative to other components within the first axial section 10.1 in such a way that a minimum cross-sectional area (meaning cross-sectional area), here in Fig.1 indicated by reference number or dotted line bracket A1, for forming a closed magnetic circuit within the MRF braking device, which is caused at least by the coil, optionally superimposed by the PM field, for the purpose of the greatest possible braking effect, i.e. the greatest possible achievable braking torque, is ensured, in particular for the purpose of the most evenly distributed magnetic flux density, in particular for the purpose of setting the operating state in an advantageous range / section of the field strength-flux density characteristic curve (particularly with regard to the aspect of magnetic saturation), in particular at a flux density in the lower single-digit Tesla range. A comparatively low flux density also has a positive effect on the achievable efficiency. The sections or corners of the coil and PM that are closest to one another can be aligned at least approximately on a straight line lying diagonally in the range of 45°.The shape of the coil can also vary or deviate from the basic square shape or cross-sectional geometry shown, in particular the one shown in . Fig. 1 left end face of the MRF braking device facing the coil may be arranged at least in sections at an angle, so that alternatively a trapezoidal shape results, as in Fig. 1 by the dotted line drawn on the coil 13. This also allows the minimum cross-sectional area A1 to be further maximized, if necessary (cf. in Fig. 1 the additional, longer dotted line bracket). This geometric modification of the coil 13 towards a rather flat / narrow design in the axial direction of extension or at least in the radial direction inward may be advantageous, particularly in the case of very tight specifications for the installation space in the axial direction; the coil is then rather axially flat and radially protruding.

[0125] It is understood that, depending on the available installation space (axial, radial) and the radial extent of the MRF braking device 10, in particular the first section 10.1 accommodating the coil and the PM, can also be designed to be axially narrower, especially if the coil 13 can be made slimmer. In this respect, the illustration chosen here is also to be understood merely as an example.

[0126] In Fig. 1 also indicates the (spatial) directions r, x, referred to here as radial and axial (spatial) directions with respect to the axial alignment of the MRF braking device. It should be understood that, in particular, the communicative and / or sensory components described here can also be arranged or assigned in other ways, depending on the manner in which the MRF braking device is integrated into the drive train or into a higher-level process, or in the context of a possibly centrally operating control / regulation system.

[0127] In Fig.2 illustrates, in particular with reference to the control / regulation aspects described here, that by means of a / the control / regulation unit 30 or by means of a computing / logic unit with a corresponding range of functions (in particular microcontroller (µC)-based control / regulation), the operating behavior of the MRF braking device 10 with regard to different operating situations BS, different operating states BZ, different operating modes BM can be implemented based on (different) parameters P and (different) threshold values ​​SW, with respective specific control / regulation specifications SR, which can each be specified in a situation-specific manner according to the present disclosure, optionally more or less in real time, optionally also relating to industrial processes such as manufacturing processes in which a drive train equipped with the MRF braking device is used.The control / regulation unit 30 is shown purely as an example in an arrangement on the MRF braking device 10; this arrangement can be modified to suit the specific application. The control / regulation specifications can, of course, also be implemented wirelessly remotely.

[0128] In Fig.Figure 3 illustrates steps of the method described here for the controlled / regulated application of a braking torque by means of an MRF braking device equipped with at least one permanent magnet, PM, with a geometrically and sized predefined MRF range. For example, a control loop can be implemented, in particular relating to steps S21, S22, i.e., a control / regulation for switching between the first and second magnetic operating states BZ1, BZ2. For example, a control loop can be implemented, in particular relating to steps S21, S23, i.e., a control / regulation for switching between the third and first magnetic operating states BZ3, BZ1. For example, a control loop can be implemented, in particular relating to step S33, i.e., a control / regulation for setting the third operating mode BM3 in the third magnetic operating state BZ3, in particular also depending on external parameters.Step S33 thus clarifies control / regulation measures for setting certain advantageous operating modes BM3 (situation-specific) for the already set magnetic operating state BZ3, e.g., in the context of a load-relieving / cooling process and / or in the context of a controlled start-up or shutdown. Step S23 can therefore also relate to a (first-time / repeated) setting of BZ3, starting from BZ1 or BZ2, after which fine-tuning can take place within the scope of step S33. In other words: After step S23, a more precise, situation-specific setting (control / regulation) of the operating mode can optionally take place within the scope of step S33 (in particular also based on drivetrain-specific criteria), e.g., also with regard to a temperature threshold.

[0129] The Fig.The diamond-shaped fields indicated in Figure 3 between the individual steps illustrate, for the person skilled in the art, application-specific parameter adjustments and / or application-specific control / regulation measures that can be implemented in a specific application, in addition to the SR specifications already outlined here, e.g., depending on specific external parameters (threshold values), for example, also with regard to a signal / data transmission functionality back to a (central) control / regulation device (e.g., central system control of a higher-level processing process). The references already given in the diamond-shaped fields are to be understood as examples (not exhaustive). List of reference symbols 1 Drivetrain, in particular drive train 2 Shaft or similar torque-transmitting drive train component 3 magnetorheological fluid (MRF) 5 Connection between rotor and shaft 7 camps 9 Seal 10 MRF braking device 10.1 first axial section, in particular coil and PM section 10.2 second axial section, in particular rotor section 10.3 third axial section, in particular cover unit 11 Stator 12 Rotor 12.1 magnetic separation 13 Coil (EM) 14 Permanent magnet (PM) 15 MRF-filled area (MRF area) 15.1 Gap 17 MRF compensation unit 17.1 first MRF compensation element 17.2 second MRF compensation element 17.3 third MRF compensation element 18 Measuring unit in particular comprising at least one sensor 18.1 permanently installed temperature sensor 19 Fasteners 20 Drive train arrangement comprising at least one MRF braking device 30 Control / regulation unit 31 Cable, especially electrical connection also for control / regulation 32 Communication module with warning functionality 40 database A1 Minimum cross-sectional area / region to form a closed magnetic circuit BS, BS1, BS2 operating situation BM, BM1, BM2, BM3 operating mode BZ, BZ1, BZ2, BZ3 magnetic operating state d15 predefined gap thickness of the MRF area M3 Residual friction torque in the PM field M10 braking torque P, P1, P2, P3, P4 Parameters relating to the MRF braking device Pext external parameter r1 is at least approximately half the radius of the rotor r2 radius of the outer surface of the rotor S1 Recording or at least processing at least one measured value and / or adjusting at least one parameter S2 Setting the desired magnetic operating state S21 Suspension of current supply to the coil S22 opposite polarity energization of the coil S23 Energize the coil S3 Setting the operating mode S33 Energize the coil within BZ3 to specify a specific BM3 S4 Control / regulation measure particularly concerning the EM field S4a Specifying or adjusting the magnetic field generated by the EM S5 Step of generating / transmitting a signal SR, SR1, SR2, SR3, SR4 control / regulation specification SR1a, SR2a, SR3a Control / regulation specification for static operating situation SR1b, SR2b, SR3b Control / regulation specification for dynamic operating situation SW, SW1, SW2, SW3, SW4 threshold r, x (spatial) directions QUOTES CONTAINED IN THE DESCRIPTION

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

[0000] EP 1 595 086 B1

[0006]

Claims

[1] MRF braking device (10) configured to apply a braking torque (M10) by means of magnetorheological fluid (3), MRF, in particular in a drive train, comprising a rotor (12), in particular a T-shaped rotor with magnetic separation (12.1), comprising a coil (13) and at least one permanent magnet (14), PM, implemented to inhibit sedimentation, wherein the rotor (12) rotates in a geometrically and volumetrically predefined MRF region (15) filled with MRF (3), wherein the coil (13) and the at least one PM (14) are arranged relative to one another in such a way that a minimum cross-sectional area (A1) is ensured for forming a / the closed magnetic circuit caused by the coil (13), wherein the MRF braking device (10) is configured to apply a / the braking torque by energizing the coil (13); characterized byin that the MRF braking device (10) is designed to level out a residual friction torque (M3) caused by the PM field by energizing, in particular counter-polar energizing, the coil (13) in a controlled / regulated manner for at least temporarily canceling the PM field for at least one operating situation (BS) detected in particular by means of the MRF braking device by setting at least one magnetic operating state (BZ) of the MRF braking device (10) as a function of at least one parameter (P) or at least one instantaneous parameter value. [2] MRF braking device according to claim 1, wherein the MRF braking device (10) is configured to control / regulate the manner of applying a braking torque (M10) for at least three magnetically different operating states (BZ) predetermined by control / regulation technology, wherein the respective magnetic operating state (BZ) is adjustable at least as a function of a momentary rotation of the rotor by energizing the coil (13) in a speed-dependent manner. [3] MRF braking device according to one of the preceding claims, wherein the MRF braking device (10) is designed to generate a braking torque at least a factor of 100 greater than the residual friction torque (M3) that can be leveled by applying current in opposite poles. [4] MRF braking device according to one of the preceding claims, wherein the MRF braking device (10) is designed to generate a braking torque (M10) at least a factor of 50 greater than the residual friction torque prevailing without counter-polar energization. [5] MRF braking device according to one of the preceding claims, wherein the setting of at least one magnetic operating state (BZ) and / or at least one operating mode (BM) is implemented by a current-based control / regulation, in particular based on at least one parameter (P) from the following group: speed-based parameter (P1), torque-based parameter (P2), rotational position-based parameter (P3), external parameter (P ext ). [6] MRF braking device according to one of the preceding claims, wherein the setting of at least one magnetic operating state (BZ) and / or at least one operating mode (BM) is implemented as a function of reaching or exceeding at least one threshold value (SW), in particular based on at least one threshold value (SW) from the following group: speed threshold value, torque or overload threshold value, time threshold value, slip or rotational position threshold value. [7] MRF braking device according to one of the preceding claims, wherein the MRF braking device (10) is configured to provide a plurality of maximum applicable braking torques (M10) graduated relative to one another in terms of height, namely at least a first and a second maximum applicable braking torque, wherein the MRF braking device (10) is configured to select at least the first or the second of the plurality of maximum applicable braking torques (M10) depending on at least one parameter (P) or at least one instantaneous parameter value for the instantaneous operating situation (BS) or for the instantaneous magnetic operating state (BZ) or for a instantaneous operating mode (BM) and to define it as the maximum applicable braking torque for a / the instantaneous operating mode (BM). [8] MRF braking device according to one of the preceding claims, wherein the MRF braking device (10) is designed for a stepped nominal torque specification, in particular as a function of at least one parameter (P) or parameter value. [9] MRF braking device according to one of the preceding claims, wherein the MRF braking device (10) is configured for a drive train-specific implemented / implementable overload protection and / or slip, in particular by specifying a maximum applicable braking torque (M10) in a braking torque range below the nominal torque of the MRF braking device (10), in particular depending on at least one parameter (P) or at least one instantaneous parameter value. [10] MRF braking device according to one of the preceding claims, wherein the MRF region (15) is geometrically and volumetrically predefined by axial sections (10.1, 10.2, 10.3) of the MRF braking device (10) which are axially fixed to one another by means of fastening means (19), wherein at least one of the axial sections together with the rotor (12) defines at least one gap thickness (d15) of the MRF region (15), in particular both at least one radial gap thickness and at least one axial gap thickness. [11] MRF braking device according to one of the preceding claims, wherein the at least one PM, the coil (13) and the rotor (12) are connected in series in the axial direction, in particular without axial overlap with one another. [12] MRF braking device according to one of the preceding claims, wherein the coil (13) projects radially outward at least approximately to the outer diameter of the rotor (12), and / or wherein the coil projects radially inward at least approximately to the outer diameter of the PM (14). [13] MRF braking device according to one of the preceding claims, wherein the at least one PM (14) and the coil (13) are arranged in a first axial section (10.1) of the MRF braking device, wherein the rotor is arranged in a second axial section (10.2) of the MRF braking device, wherein the first and second axial sections are screwed together at the end faces, in particular at least radially abutting against one another. [14] MRF braking device according to one of the preceding claims, wherein the rotor is enclosed by three axial sections (10.1, 10.2, 10.3) of the MRF braking device, which are fixed relative to one another in a predefined manner, in particular are screwed together, and thereby predefine the geometry and the size of the MRF region (15). [15] MRF braking device according to one of the preceding claims, wherein the MRF braking device (10) comprises a control / regulation unit (30) or is communicatively connected thereto, which is in communication with a measuring unit (18) comprising at least one sensor, in particular from the following group: rotary encoder, rotation / braking torque sensor, angular velocity sensor, rotational position sensor, temperature sensor, acceleration sensor, displacement / distance sensor; wherein the MRF braking device (10) is configured to determine at least one parameter or at least one instantaneous parameter value based on instantaneous measured values ​​or measured values ​​already stored in a data memory of the control / regulation unit (30). [16] MRF braking device according to one of the preceding claims, wherein the MRF braking device (10) has a permanently installed temperature sensor (18.1) which detects the MRF area (15) by means of a sensor. [17] Drive train arrangement (20) comprising at least one MRF braking device (10) according to one of the preceding claims. [18] A computer program product comprising instructions which, when the computer program product is executed on a computer or in a control / regulation unit (30), cause the computer to specify steps for controlling / regulating a method for the controlled / regulated application of a braking torque by means of an MRF braking device (10) equipped with at least one permanent magnet (14), PM, with a geometrically and sized predefined MRF range (15), in particular in a drive train, according to the following steps: specifying a current operating mode (BM) of the MRF braking device (10) based on one of at least three adjustable magnetic operating states (BZ) of the MRF braking device (10) by controlled / regulated energisation of at least one coil (13) of the MRF braking device (10), controlled / regulated levelling of a residual friction torque caused by the PM field by energisation,in particular, applying opposite polarity current to the coil (13) for at least temporary cancellation of the PM field for at least one operating situation (BS) detected in particular by means of the MRF braking device (10) by setting at least one magnetic operating state (BZ) of the MRF braking device (10) as a function of at least one parameter (P) or at least one instantaneous parameter value. [19] Computer program product according to the preceding claim, wherein the computer program product is implemented in such a way that at least one of the magnetic operating states (BZ), in particular the first magnetic operating state and / or the second magnetic operating state, is further predetermined in terms of control / regulation technology as a function of at least one time parameter, in particular when a predetermined maximum duration is exceeded, in particular when there is no rotation. [20] Computer program product according to one of claims 18 to 19, wherein the computer program product is implemented such that a residual friction torque (M3) caused by the PM field is leveled by energizing the coil (13) in opposite polarity, in particular below 1% of the nominal torque, in particular below 1 Nm. [21] Computer program product according to one of claims 18 to 20, wherein the computer program product is implemented in such a way that, on the one hand, the magnetic operating state (BZ) is predetermined in terms of control / regulation technology at least as a function of a current rotation, wherein, on the other hand, the current operating mode (BM) of the MRF braking device (10), in particular for the at least one third magnetic operating state, is also predetermined in terms of control / regulation technology, in particular based on at least one parameter from the following group: speed-based parameter (P1), torque-based parameter (P2), rotational position-based parameter (P3), external parameter (P ext ). [22] Computer program product according to one of claims 18 to 21, wherein the computer program product is implemented such that at least one operating mode in at least one magnetic operating state (BZ) of the MRF braking device (10) is set as a function of at least one parameter (P) or at least one instantaneous parameter value such that the MRF braking device is operated according to a stepped nominal torque specification based on at least two overload threshold values. [23] Computer program product according to one of claims 18 to 22, wherein the computer program product is implemented such that at least one operating mode in at least one magnetic operating state (BZ) of the MRF braking device (10) is set as a function of at least one parameter (P) or at least one instantaneous parameter value such that the MRF braking device (10) is operated according to a predefined range of a rotational speed difference corresponding to a predefined slip or with respect to at least one threshold value relating to a maximum deviation from the predefined slip. [24] Computer program product comprising instructions which, when the computer program product is executed on a computer or in a control / regulation unit (30), cause the latter to carry out steps for controlling / regulating according to one of claims 18 to 23 on the computer or in / by means of the control / regulation unit (30), in particular a computer program product configured to specify a current operating mode (BM) of an MRF braking device (10) with a predefined MRF range (15) by controlled / regulated setting of at least one magnetic operating state (BZ) of the MRF braking device (10) as a function of at least one parameter (P) or current parameter value. [25] Use of three axial sections (10.1, 10.2, 10.3) that can be fixed axially to one another for the geometric and volumetric definition and delimitation of an MRF region (15) of an MRF braking device (10) with a permanent magnet (14), PM, that can be set in at least three magnetic operating states (BZ), in particular in or for a drive train, for providing the MRF braking device (10) with an electromagnetically levelled residual friction torque in a rotating operating situation (BS2) when the braking effect is not called up and for providing the MRF braking device (10) with a PM field, in particular in a non-rotating operating situation (BS1) when the braking effect is not called up and for providing the MRF braking device (10) with a PM field and a magnetically equivalent EM field, in particular in a rotating operating situation (BS2) when the braking effect is called up,wherein the EM field for applying the braking effect is generated as a function of at least one parameter (P) from the following group: time parameters, in particular relating to a maximum duration without rotation, rotation state parameters and speed parameters, acceleration parameters, temperature parameters, braking effect requirement parameters, rate of change parameters relating to at least one of the parameters, torque parameters, rotational position parameters. [26] Use of a control / regulation unit (30) for specifying the type and manner of energization of at least one coil (13) of an MRF braking device (10) with a permanent magnet (14), PM, and a geometrically and volumetrically predefined MRF region (15) for specifying a / the current operating mode (BM) of the MRF braking device (10), in particular depending on both a current operating situation (BS) and at least one / the third magnetic operating state (BZ3) of the MRF braking device (10), in which a / the PM field and, with the same magnetic effect, an / the EM field are applied to the magnetorheological fluid (3), MRF, wherein the type and manner of energization is generated depending on at least one parameter (P) from the following group: time parameters, in particular relating to a maximum duration without rotation, rotation state parameters and speed parameters, acceleration parameters, temperature parameters, braking effect requirement parameters,Rate of change parameter relating to at least one of the parameters, torque parameter, rotational position parameter; wherein, depending on a change from an operating situation (BS) without rotation to an operating situation (BS) with rotation, switching is carried out automatically from the first to the second magnetic operating state (BZ1, BZ2) if a braking effect is not requested, and switching is carried out automatically from the first to the third magnetic operating state (BZ1, BZ3) if a braking effect is requested. [27] Use of an MRF braking device (10) according to one of claims 1 to 16 in an industrial process for maintaining at least one external parameter (Pext) relating to a control / regulating variable of the industrial process. [28] Use of an MRF braking device (10) according to one of claims 1 to 16 in a drive train (20) for maintaining at least one external parameter (Pext) relating to a control / regulating variable for the operation of the drive train.

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