Control device with mechanically guided members for enabling relative movement - Patents.com

Abstract

1. A control device comprising at least one permanent magnet (5, 7; 7a, 7b; 350, 351) and a mechanically guided member for enabling a relative movement between: a. a first ferromagnetic structure (1, 100); and b. a second ferromagnetic structure (3; 200), comprising at least one electric coil (8, 9; 250), said electric coil (8, 9; 250) changing the magnetization state of said second ferromagnetic structure (3, 200) according to the direction and the amplitude of a current flowing in said coil (8, 9; 250), said device further comprising position detection means (10) for detecting the relative position of the first and second ferromagnetic structures and a circuit for driving a supply current of said coil (8, 9; 250), which varies as a function of a signal delivered by the position detection means (10).

Description

[Technical field]

[0001] The present invention relates to the field of configurable control devices comprising a control button or accessory movable according to a rotation or linear displacement, for example a control button associated with an electromagnetic sensor for providing an analog signal representative of the position and / or displacement of the control button. The fact of being configurable makes it possible to change the state of the button, for example with a variable index or variable stop.

[0002] In particular, the present invention relates to a configurable haptic control device constituting a man-machine interface in which the haptic sensation can be altered by manual selection or by automatic contextual selection among two or more activatable modes, including a notching sensation, regular or irregular indexing, or a stopping sensation.

[0003] The desired objective is to create a haptic feedback by touch, so that the user feels a tactile effect when manipulating this control member, for example by passing a hard point, reaching a stop, or by regular or irregular indexing, so that as a result of the user's manipulation, he has a physical sensation that the manipulation has actually been performed, or he perceives the number of increments tactilely. It is also important that the sensation felt can be dynamically changed, for example depending on the type of control performed with the same button or when an action is performed by the system, thereby enriching the information given and the user experience. This change in sensation can be controlled manually, for example by a selection button, or in a situation-dependent, automatically controlled manner.

[0004] This control device is used, for example, in the automotive industry: it may be used in a vehicle to control the operation and regulation of, for example, lights, mirrors, windscreen wipers, air conditioning, infotainment, radio, or gearbox control.

[0005] The invention is also applicable in many industries, particularly in the control of domestic or industrial equipment, for example in the form of control buttons for domestic or audiovisual equipment, whose indexing pitch and hardness can be varied depending on the situation to provide a soft feel to explore a wide adjustment range, then provide index marks for fine adjustment, or vice versa to explore a wider range with successive jumps, then provide a soft adjustment giving a sense of continuity, otherwise a stop feel at the end of progression.

[0006] The device may also be associated with an electric motor to achieve an adjustable force, such as a controllable residual torque (when there is no current in the motor), or a force to return to a predefined stable position, a braking force, or a controllable stopping force. [Background technology]

[0007] Patent application WO 2020 / 109744 is known in the art and describes an adjustable resistance device comprising a mechanically guided member for enabling a displacement along a predetermined trajectory and means for magnetically indexing said displacement by magnetic interaction between a first ferromagnetic structure and a second ferromagnetic structure rigidly connected to a magnet, characterized in that the magnet is at least partially surrounded by an electric coil that modifies the magnetization of the permanent magnet according to the direction and amplitude of a current flowing through the coil.

[0008] US Patent Application Publication No. 2020 / 005977 describes a mouse with a rotary input control having a wheel and a set of electro-permanent magnets (EPMs), the EPM assembly comprising a permanent magnet and a magnetization assembly configured to control polarization of the permanent magnets to change the set of permanent electromagnets from a first state in which the EPM assembly applies a first resistance profile to the wheel to a second state in which the EPM assembly applies a second resistance profile to the wheel. The EPM assembly includes magnetic conductive elements positioned on either end of the permanent electromagnets, each magnetic conductive element comprising a respective plurality of teeth projecting radially toward the wheel. EP 1999534 describes a blocking device for at least partially blocking relative movement between a stationary part and a mobile part of a device, the device comprising at least one permanent magnet, an electromagnet on a ferromagnetic core, a stop profile in the mobile part and a blocking element capable of engaging with the stop profile, the permanent magnet being movably arranged in the device between at least two extreme positions, the ferromagnetic core being essentially U-shaped, the permanent magnet being located at the end of a branch of the ferromagnetic core in each extreme position, the electromagnet and the mobile permanent magnet arranged on the ferromagnetic core being made such that the blocking element follows the position of the permanent magnet.

[0009] EP 1 891 494 describes a simple and reliable device in which an electromagnet moves a ball from a rest position to a blocking position, which mechanically blocks relative movement between two elements.

[0010] EP 0018292 describes an electrohydraulic rotary brake comprising an inner core, at least one excitation winding, a cylindrical non-magnetic sheath, a cylindrical bore outside the core and sheath and off-centered with respect to the cylindrical periphery of the sheath, a recess provided with magnetizable sliding vanes, and an annular portion containing brake fluid.

[0011] U.S. Pat. No. 4,408,859 describes a speed regulator for a camera having first speed control means arranged to synchronously drive at an increased speed a drive element which drives a high speed acting element into a predetermined position, and second speed control means arranged to brake the drive force of the drive element.

[0012] Shortcomings of the prior art Prior art solutions are not entirely satisfactory because changing the nature of the haptic interaction, for example by decreasing the stiffness when the control button is close to the target position and, conversely, increasing the stiffness when the target position is far away, requires movements with larger jumps, is limited to two modes, and does not allow for more concise adjustment of the sensation, for example by changing the indexing pitch or by providing different levels of stiffness or even inhibition.

[0013] Furthermore, US 2017 / 0045958 indeed proposes a dynamic adjustment of the magnetic field and the effect felt on the turn controlled by a magnetorheological fluid, but this solution has notably the drawback of using a magnetorheological fluid, which requires unfavorable design constraints, especially with regard to sealing.

[0014] Most known solutions for generating variable friction must be continuously powered to simulate the notches, which leads to continuous power consumption, which is a disadvantage for applications where energy conservation is a key issue, such as battery-powered devices or electric vehicles. These known solutions also create an unusual sensation without a spring effect (the force provided by the user is always positive), making the tactile sensation less intuitive.

[0015] Finally, the prior art solutions make it possible to adjust the amplitude of the torque, varying between zero value and a maximum value of resistance to the movement, but do not allow the sign of the torque to be changed, thus making it impossible to generate, for example, sensations corresponding to alternating positive and negative torques traditionally with passive interfaces. Summary of the Invention [Means for solving the problem]

[0016] To address these drawbacks, the present invention in its most general sense relates to a control device exhibiting the features set forth in claim 1.

[0017] The device according to the invention comprises a mechanically guided member, a first ferromagnetic structure, a mechanically guided member enabling a relative movement between the second ferromagnetic structure and the at least one electric coil, the at least one electric coil changing the magnetization state of the second ferromagnetic structure along the direction and amplitude of a current flowing in the coil; Further included is a circuit for controlling a supply current to the coil as a function of an input signal representative of the relative position of the ferromagnetic structure.

[0018] Advantageously, the supply current of said coil is controlled as a function not only of the state of the selector but also of a status input signal representative of the overall state of the equipment being controlled.

[0019] The force exerted by such a device can be dynamically controlled as a function of the position of the control button, allowing the reference position to be adjusted in real time during button actuation, as opposed to prior art solutions in which the reference position was fixed for each mode of operation.

[0020] Thus, the present invention allows for varying the pitch of indexing over the travel of a control button, allowing for example a fine notching feel in fine adjustment areas and a coarser notching feel with a larger pitch in adjustment areas of less interest. It also allows for dynamically revealing or removing stops as a function of external data and button position.

[0021] In a button delivering a notched sensation, the device comprises means for magnetic indexing of the movement by magnetic interaction between the ferromagnetic structures, and the circuit for controlling the supply current of the coil controls the modification of the magnetization of the permanent magnet according to a number of modes, some of which clear a portion of the indexed position.

[0022] Advantageously, said first ferromagnetic structure and said second ferromagnetic structure each have a plurality of radial teeth which cooperate to create said magnetic indexing means.

[0023] According to one alternative, the control device further comprises means for delivering a signal used by the control circuit to select a variable force mode from a plurality of predefined variable force modes and to change the supply mode of the coil.

[0024] According to another feature, the control device comprises: an interface to a controlled device delivering a signal used by said control circuit to change the supply mode of said coil; a position sensor capable of measuring the position of a first ferromagnetic structure in order to provide to the control circuit of the supply current of the coil the input signal representative of the relative positions of the first ferromagnetic structure and the second ferromagnetic structure; an electronic memory for recording at least two control laws, the electronic circuit comprising an input for selecting one of said control laws; an active stop consisting of a first structure moving relative to a second structure and at least one braking element preventing relative movement between the first structure and a second structure by magnetic interaction between the braking elements, the second structure comprising a ferromagnetic body at least partially surrounded by an electric coil, the electrical supply of the coil modifying the magnetization of the ferromagnetic body, the magnetization state of the ferromagnetic body adjusting the braking force between the first structure and the second structure; - means for magnetic indexing of the movement between the first and second ferromagnetic structures, the indexing means being either directly integrated into the first and second structures or generated using two complementary ferromagnetic structures in accordance with the teachings of the claims, one of the complementary ferromagnetic structures being integral with the first or second ferromagnetic structure and the other complementary ferromagnetic structure being integral with the other of the first and second ferromagnetic structures.

[0025] Advantageously, the device according to the invention has one or several of the following technical features: a control circuit controlling the supply current of the coil as a function of a signal representative of the relative position of the first ferromagnetic structure and the second ferromagnetic structure; a control circuit controlling the supply current of the coil as a function of a signal representative of the relative speed of movement of the first ferromagnetic structure and the second ferromagnetic structure; the permanent magnets of the second ferromagnetic structure are made of a hard ferromagnetic material having a coercive force of less than or equal to 100 kA / m; the second ferromagnetic structure being integral with a second permanent magnet made of a hard ferromagnetic material having a coercivity greater than 100 kA / m;

[0026] According to an alternative embodiment of the invention, the second ferromagnetic structure comprises at least two permanent magnets, each at least partially surrounded by an electric coil that changes its magnetization in a direction and amplitude of a current flowing in the coil, the electronic control circuit determining a supply current for each of the coils as a function of the relative position of the ferromagnetic structures and of a state of a control for selecting an operating mode from a plurality of operating modes; the first and second structures have teeth, the second ferromagnetic structure consisting of two semi-tubular toothed parts connected on the one hand by a second magnet and on the other hand by the first magnet, - The magnetization directions of the two magnets are the same, the magnetization state of the second ferromagnetic structure is changed in relative positions of the first and second structures located within an interval of more or less 25% of the period of indexing of the indexing means, the interval being centred on a stable equilibrium position of the indexing means; the magnetization state of the second ferromagnetic structure is changed in relative positions of the first and second structures located within an interval of more or less 10% of the period of indexing of the indexing means, the interval being centred on a stable equilibrium position of the indexing means; the braking element is capable of adjusting the braking force between the first structure and the second structure in a single direction of the relative movement; the second braking element is capable of adjusting the braking force between said first structure and said second structure in an opposite direction; the braking element is capable of adjusting the braking force between the first structure and the second structure in both directions of the relative movement; the damping element damps the relative movement between the first structure and the second structure; said braking element; said first structure; configured to interfere with a magnetic interaction between the second structure and the ferromagnetic bodies consist of a soft ferromagnetic material, the magnetization of which is zero in the absence of a current supplying the coil, said ferromagnetic bodies having part-cylindrical housings, each capable of receiving a cylindrical braking element; The braking elements are articulated about an off-center axis, such that movement of one of the braking elements in one direction brings the braking element into contact with the first structure, or in the opposite direction causes the braking element to retract into its housing.

[0027] when the braking element is in contact with the first structure, a movement of the first structure in one direction, due to its eccentric rotation, causes a blocking of the first structure by the abutment of the braking element; the ferromagnetic body comprises a permanent magnet at least partially surrounded by said coil, the amplitude of the magnetization of the permanent magnet being adjusted by said coil, The coil is controlled by a computer associated with a memory that periodically records the state of the control device to determine the most frequent state.

[0028] The invention also relates to a man-machine interface comprising a display screen, characterised in that it further comprises at least one control device arranged on a viewing surface of the display screen and having the features according to at least one of the preceding claims.

[0029] Advantageously, the control device has a central recess for displaying, in a screen zone arranged behind the central recess, information determined as a function of the state of the control device.

[0030] The invention further relates to an actuator comprising a module for driving an output member, characterized in that the actuator further comprises a control device coupled to said output member and having the features according to at least one of the preceding claims. [Brief description of the drawings]

[0031] The invention will be better understood on reading the following description of non-limiting embodiments illustrated by the attached drawings, in which: [Figure 1]1A-1D are perspective and cross-sectional views of an example of an active notching device provided with active stops. [Diagram 2] A functional diagram is shown. [Diagram 3] 1 shows a schematic diagram of an example of a modulation sequence of the torque felt as a function of the angular position. [Figure 4a] FIG. 2 is a perspective view of a first example of an electromagnetic structure of an active notching device. [Figure 4b] A cross-sectional view of the example of FIG. 4a is shown. [Figure 4c] A top view of the example of FIG. 4a is shown. [Diagram 5] To provide notching, torque measurements obtained when a low coercivity magnet is magnetized to saturation are shown. [Figure 6] 1 shows torque measurements felt during alternating activation of two magnetization states steps of zero magnetization or two magnetization states of a given level of a permanent magnet as a function of the position of the actuated button. [Figure 7] 1 shows torque measurements felt during alternating activation of three magnetization states of a step of zero magnetization or two magnetization states of a given level of a permanent magnet as a function of the position of the actuated button. [Figure 8] 1 is a schematic representation of the torque felt during alternating activation at each step of N magnetization states of a permanent magnet that decreases continuously as a function of the position of an actuated button. [Figure 9] 1 is a schematic representation of the torque felt during activation of N magnetization states of a permanent magnet according to a prerecorded profile as a function of the position of the actuated button. [Figure 10] FIG. 13 shows a perspective view of an alternative embodiment of an active notching device. [Figure 11] 4 shows the force curves of the prior alternatives. [Figure 12a] FIG. 2 shows a perspective view of a first embodiment of an active stopping device having a rotationally moving and rotationally guided braking element. [Figure 12b] 12b shows the torque generated on the braking element of the stopping device shown in FIG. 12a. [Figure 13a] 13 illustrates an alternative embodiment of an active stopping device having multiple stable positions without current. [Figure 13b] 13b shows the torque generated on the braking element of the stopping device shown in FIG. 13a. [Figure 14] 13 shows an alternative embodiment of an active stopping device having a rotational relative movement and a linear guide braking element. [Figure 15] 13 illustrates an alternative embodiment of an active stopping device having linear relative motion and a single braking element. [Figure 16a] 13 illustrates an alternative embodiment of an active stop device having indexing stops for two different states: free and blocked. [Figure 16b] 13 illustrates an alternative embodiment of an active stop device having indexing stops for two different states: free and blocked. [Figure 17] 1 shows the integration of a leading stop device into a notching system according to the present invention. [Figure 18] 1 illustrates the integration of a control device and a display screen according to the present invention. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0032] Force Adjustment Device The present invention relates to an adjustable force device, active notching and / or active stops, which allows to dynamically modify the force by computer control, which changes as a function of the position of the control button. This force can be likened to that of an indexing control with variable indexing, regular or not, and / or controlled stops. The stops can be very clear, i.e. causing a complete blockage of the system in a given direction, or indicated by being embodied by a greater friction starting from a given position. The use of such a device is particularly advantageous for providing tactile feedback to the user, but is also interesting for generating a modulation of the force on the member to be driven.

[0033] Depending on the application, the force to be adjusted may vary, in some cases only the notching effect is desired, for other purposes only the stopping effect is required, and in other cases both are implemented, but not necessarily in conjunction. Thus, various solutions are presented throughout the exemplary embodiments.

[0034] FIG. 1 shows a first embodiment incorporating an active notching device (80) and an active stopping device (90) in a haptic system with rotational actuation. In the exemplary embodiment of FIG. 1, the devices each have a cylindrical shape and are axially superimposed. This first embodiment must be interpreted as integrating two devices according to the most general claims, one dedicated to notching and the other dedicated to adjustable stopping. This embodiment is preferred when both notching and stopping functions are desired in a completely uncorrelated manner, and FIG. 17, for its part, shows the interweaving of both functions in a single device, but with interdependence.

[0035] The notching device (80), which will be explained in more detail through other examples, consists of a first structure (1) with a soft ferromagnetic material and a second structure (3) associating a circuit made of the soft ferromagnetic material with a permanent magnet (7) and a semi-permanent magnet at least partially surrounded by an electric coil (8), said structures being capable of relative rotational movement. The notching effect is obtained due to the cooperation of teeth (2, 11) constituting the opposing faces of the ferromagnetic material parts of said first structure (1) and second structure (3).

[0036] The stopping device (90), which will also be explained more fully through different examples, consists of a first structure (100) and a second structure (200) capable of relative movement in rotation, and damping elements (310, 320) for preventing the relative movement of said structures. The first structure (100) comprises a soft ferromagnetic material (210) capable of changing its magnetization state as a function of the supply current of a coil (250), the magnetization state of the ferromagnetic material (210) acting on the position of the damping elements (310, 320) to adjust the resistance to the relative movement of said first structure (100) and second structure (200).

[0037] In this exemplary embodiment, the tactile system is in the form of a button, the external flange actuated by the user is not shown, which is rigidly connected to the first structure (1) of the notching device (80), the first structure (100) of the braking device (90) and the shaft (6), which together form a first integral assembly, which serves to support the structure (100) and to guide the first integral assembly in rotation relative to the second integral assembly. This second integral assembly is intended to remain stationary during use of the system and comprises the second structure (3) of the notching device (80) as well as the second structure (200), an electronic circuit (12) comprising means for guiding the braking elements (310, 320) of the braking device (90) and means for controlling the coils (8, 250).

[0038] The relative movement of the two integral assemblies is measured in this embodiment by a magnetic position sensor (10) generated by the cooperation of a magnet that is integral to the shaft (6) and a magnetic sensing probe integrated into electronic circuitry (12).

[0039] This first example of integration in the form of a tactile button is not limiting of the invention, as the notching device (80) and the braking device (90) can be produced in a wide variety of ways and can be used together or independently to adjust the force according to different types of degrees of freedom, or even several degrees of freedom.

[0040] This type of active device, especially in the form of a stop only, can also be important for use with a motor, where the stop is able to brake or block the motion of that motor. Indexing features can be integrated into the motor to locally adjust the "geared torque" of the motor to create an irreversible position for the geared motor.

[0041] Functional Architecture As shown in Figure 2, this device is distinguished from the one described in patent application WO 2020 / 109744 (A2) due to the fact that the magnetic system (20) comprises a position sensor (10) (for example of the optical or electromagnetic, or even inductive type) providing an electrical signal representative of the relative position of the structures (1, 3), and a control circuit (15), for example a microcontroller or FPGA circuit, as well as a user interface (25) optionally comprising a selector making it possible to act on the relative position of the structures (1, 3) and to select a haptic mode from a number of recorded modes, resulting in different changes in the torque profile and different indexing pitches or gaps.

[0042] The control circuit determines the direction and amplitude of the supply current of the coil (or of the coils, if the electromagnetic system (20) comprises several coils) as a function of the relative position of the structures (1, 3) comprising ferromagnetic material on the one hand and as a function of a control law recorded in the memory on the other hand, optionally according to the state of a manual selector controlled by a user or, depending on the situation, according to the state of a manual selector controlled by a complementary electronic circuit whose state is controlled by the device.

[0043] The energy required to magnetize the coil, even though it remains low overall due to its pulsed nature, is difficult to access directly by the power supply network, thus imposing a local energy reserve, which also requires maintaining this reserve at any instant available to respond to any magnetization event, usually in the form of a voltage greater than the voltage provided by the system to the device.

[0044] Depending on the coil supply direction, the magnetization or demagnetization of the second ferromagnetic structure (3) is caused as a function of the spatial position of the button, and some notches can be selectively turned "off", which then allows to vary the torque (amplitude and frequency) with potentially very large fields.

[0045] The possibility to freely change the indexing makes it possible, for example, to use the same control button for different interaction modes.

[0046] The infotainment button can thus manage an alphabetical table where 30 letters and therefore 30 notches would be desirable, a digital table of numbers with approximately 10 notches, a freewheel mode, i.e. a mode with a continuously increasing index amplitude to manage the sound level of the audio system, and a mode that changes the number of notches depending on the situation, for example selecting a first function parameter by an alphabetical mode with 36 notches, then selecting a second digital parameter by a digital mode with 10 notches, then a third parameter by a continuous mode with no notches, and finally a position-adjustable stop that tactilely indicates that the end of the selection list has been reached.

[0047] It is also possible to vary the distance between two steps in the button progression, for example using separate steps in the range of values ​​rarely used for coarse adjustment and closer steps in the most relevant range to allow fine adjustment in this zone, resulting in a stop at the desired position. The limits of the range can be determined by supervised learning from previous settings to suggest for future settings a narrowed adjustment range around the values ​​most frequently selected during past use.

[0048] Figure 3 shows an example of a sequence that can be programmed. More specifically, during rotation of the infotainment button (13), a first angular sector can be calibrated with free rotation, then activating the notching mode at a given position, then the force profile shown in box 2 is obtained. The amplitude of the indexing is then increased over several steps and then decreased to its initial level. After several steps, one of the two modes or one notch is deactivated before reaching the activation position of the stop, as shown in box 1.

[0049] It should be noted that FIG. 3 is presented for illustrative purposes only and is not intended to limit the invention in any way to the order described, nor is it intended to limit the invention to the embodiment presented.

[0050] Electromechanical architecture of indexing device The electromechanical architecture in particular follows one of the examples described in patent application WO 2020 / 109744(A2), the contents of which are incorporated by reference into this patent.

[0051] Figure 4a shows a schematic perspective view of a first embodiment of the electromagnetic structure of an indexing device, while Figures 4b and 4c show a cross-sectional view and a top view, respectively, of such a device, in which the thick arrows indicate the direction of magnetization of the elements.

[0052] This example of an indexing device consists of a first structure (1) formed by a toothed cylinder made of ferromagnetic material and having, in the example shown, 20 radially extending teeth (2), the number of teeth being unlimited, which rotates about an axis (6) and is coupled to a manually actuated control button (not visible here).

[0053] A second toothed ferromagnetic structure (3) is arranged coaxially inside this first structure (1) and is stationary with respect to the movements of the first structure (1). This second ferromagnetic structure (3) consists of two stationary semi-tubular parts (4a, 4b) with teeth (11) extending radially towards the teeth (2) of the first structure and having the same angular deviation as the angular deviation of the teeth (2) of the first structure (1). Such an identical angular deviation for the teeth (2) and (11) makes it possible to maximize the force between the first structure (1) and the second structure (3) and therefore the haptic sensation given to the user. However, the adjustment of this haptic sensation is advantageously made possible by the number of teeth on the two structures (1, 3), possibly by a difference in the angular deviation between the teeth (2, 11) or even by a different width of the teeth (2, 11) between the two structures (1, 3).

[0054] The two semi-tubular parts (4a, 4b) are connected on the one hand by a first permanent magnet (5), which preferentially has a high energy, typically 600 kA / m, in any case a coercive force greater than 100 kA / m. The direction of magnetization is along the largest dimension of the magnet, in this case perpendicular to the axis of rotation (6). The permanent magnet (5) has a constant magnetic field generating feature and must not be demagnetized during use of the device.

[0055] These two semi-tubular parts (4a, 4b) are also connected on the other hand by a second magnet (7) with low coercivity, i.e. a semi-permanent or AlNiCo type magnet, typically with a permanence of 1.2 Tesla and a typical coercivity of 50 kA / m, in any case less than 100 kA / m. The direction of magnetization is along the largest dimension of the magnet, such that the magnetic flux of the two magnets (5) and (7) is additive or subtractive, depending on the magnetization given to the second low-coercivity magnet (7), and the magnetic flux flows inside the semi-tubular parts (4a, 4b). The low coercivity of the magnet (7) is necessary to allow it to be easily magnetized or demagnetized by coils located around it, which is done with limited energy, allowing the use of the magnet in an integrated device without the use of powerful and expensive electronics.

[0056] This second magnet (7) is placed parallel to the first magnet (5) and is surrounded by two electric coils (8, 9). In an alternative embodiment, it is possible to install only one coil, with the two coils (8 and 9) being placed on either side of the guide axis (6) in this example for balance and space optimization.

[0057] As an example, each coil consists of 56 turns (28 turns / pocket) in series with 0.28 mm copper wire, and the coils have a termination resistance of 0.264 Ω.

[0058] To adjust the direction and / or amplitude of the polarity of the magnetization of the low coercivity magnet (7), a current in the form of a direct current or an electric pulse, for example given by discharging a capacitor, is applied to the coils (8, 9). By way of example, a current of 13 Amperes generating a magnetomotive force of about 730 At makes it possible to modify the magnetization.

[0059] The operation of this first embodiment is as follows: when a direct current or current pulse in a positive direction (arbitrary reference) flows through the coils (8, 9) creating an additive magnetic field between the two coils, the low coercivity magnet (7) is magnetized in such a direction that the magnetic flux of the two magnets is additive and flows mainly in a loop through the two magnets (5, 7) and the semi-tubular parts (4a, 4b). As a result, there is little or no magnetic flux through the first structure (1), there is little or no coupling between the two structures (1, 3) and therefore the user activating the structure does not feel any notching. In this particular example, the magnetization of the two magnets (5, 7) is parallel and perpendicular to the median plane between the two semi-tubular parts (3, 4), although this configuration is not exclusive.

[0060] When a current pulse in the negative direction (arbitrary reference) flows through the coils (8, 9) creating an additive magnetic field again between the two coils, the low coercivity magnet (7) is magnetized in a direction such that the magnetic flux of the two magnets is subtractive and flows mainly in a loop through the two magnets (5, 7) and the two toothed structures (1, 3). This results in significant coupling or notching, and a significant indexing sensation is perceived by the user of the device, and thus the user feels the notching.

[0061] The coils (8, 9) are powered by currents driven by a control circuit that receives as input the angular position of the external yoke (1) relative to the yokes (4a, 4b). The strength of the current in the coils (8, 9) advantageously makes it possible to modulate the tactile sensation by directly influencing the strength of the magnetization of the low coercivity magnet (7) and thus the coupling magnetic flux between the stationary and mobile structures.

[0062] Example of torque profile generated by a notching device Figures 5 to 9 show different examples of torque profiles according to the invention. Figure 5 shows the variation of the amplitude (51) obtained as a function of the relative position (52) of the two toothed structures (1, 3), when the low coercivity magnet (7) is magnetized to saturation, providing a maximum amplitude notch (55). A typical torque variation profile (50) is obtained for this type of structure, with the motor torque alternating when the amplitude is positive and braking when the amplitude is negative.

[0063] 6 and 7 show the torque profiles resulting from the activation and deactivation of the notching, at different angular positions (60), by a circuit for controlling the supply current of the coils, so as to eliminate, respectively, one of the two felt notches or two of the three felt notches, with respect to the "passive" reference notching shown in FIG. 5. The activation and deactivation angular positions (60) are shown at the top of FIGS. 6 and 7, the scale (53) representing the triggering of the change of state, without representing the value of the current through the coils. Here, the activation and deactivation angular positions (60) correspond to stable or unstable equilibrium positions of the magnetic interaction of the two toothed structures. The selection of this position makes it possible to locally adjust the torque transition and refine the user's sensation, thus making it possible to make the transition occur at an equilibrium point, i.e. where the force is lowest, making this state change transparent to the user. The stable equilibrium position corresponds to a zero torque position with a negative derivative, while the unstable equilibrium position has a positive derivative of the torque.

[0064] The relationship between the position returned by the sensor and the position of the balance point of each notch can be determined by the control circuit at power up, and the only stored information required is the number of notches the device has. Thus, at each power up, the device can estimate the angular position of all notches from the moment they are in a stable position. It is also possible to use absolute sensors.

[0065] Fig. 8 shows the modification of the notching amplitude by a circuit for controlling the supply current of the coils at different angular positions (60) to obtain a gradually decreasing notching amplitude as a function of the relative angular position (52) of the two magnetic structures. The angular positions (60) of the amplitude modification are for example performed at unstable equilibrium positions of the magnetic interaction between the two toothed structures. The signal for triggering the amplitude modification represented in the upper part of Fig. 8 does not represent the current through the coils.

[0066] To obtain the different magnetization amplitudes, two methods are preferred, without limiting the invention. The first method consists of applying a demagnetizing current cycle, then a magnetizing current in succession to reach the desired notching level. This method has the advantage of simplifying the control electronics, since the demagnetizing cycle does not depend on the initial magnetization level, and the relationship between the magnetizing current and the magnetization level obtained from the zero level is an easily characterizable datum.

[0067] The second method consists in characterizing the relationship between the permanent magnetization and the magnetizing current jointly for all pairs of initial and final magnetization levels that it is desired to obtain. This method is more complex to implement, but has the advantage of reducing the power consumption of the device during use, as well as limiting the fluctuations in the force felt by the user when changing the level of magnetization.

[0068] FIG. 9 shows another notching modification made possible by the device according to the invention. For example, for an angular range (66), the circuit for controlling the supply current of the coils can eliminate all the negative alternations of the pairs, so that over this range, only a resistance sensation or a zero sensation is obtained for the user. The sensation over this angular range (66) corresponds to the friction modulation effect that can be obtained with the structures presented in the prior art using magnetorheological fluids. On the other hand, the device according to the invention has a completely new haptic effect, as shown over the angular range (65), which eliminates all the positive alternations of the torque. The sensory effect felt by the user is therefore an alternation of the motor torque and zero torque, whose very different sensation makes it possible to associate alternative information with it. As shown by the transitions (61, 62), a change of the magnetization state performed outside the equilibrium position leads to a large variation of the force perceived by the user. Therefore, such transitions should be avoided as soon as it is desired to obtain a state change as transparent as possible for the user. In fact, the electric pulses generated to modify the magnetization state of the semi-permanent magnets lead to the generation of a high amplitude magnetic field, modifying the force applied to the user-movable structure. This force variation is zero when the structure is in the relative angular equilibrium position. As a criterion, therefore, a modification of the notching is preferentially generated for angular positions located less than 25% of the period of the notching of the indexing means around the equilibrium position, if it is desired that this modification is transparent to the user. This represents a good compromise between the quality of sensation by the user and the accuracy required of the position sensor. In the most demanding specifications, the sensation can be improved by limiting the interval to 10% of the period of the notching of the indexing means.

[0069] Alternative example of a notching device with two coil magnets FIG. 10 shows a diagram of an alternative embodiment of the second ferromagnetic structure (3) having two semi-permanent magnets (7a, 7b), for example of the AlNiCo type, each extending from a ferromagnetic yoke (39) common to the two magnets (7a, 7b) to a yoke (40, 41), said yokes (40, 41) being connected by a highly permanent magnet (5).

[0070] The yoke (39) has no teeth in the illustrated example. The yokes (40, 41) have steps spaced at different angular intervals, which correspond to frequencies of 18 and 36 notches per revolution, respectively.

[0071] The magnets (7a, 7b) are each surrounded by a coil (not shown) which allows the polarity and strength of the magnetization of each of said magnets (7a, 7b) to be reversed, while the magnetization of magnet (5) is not changed. Each of the coils is supplied with a current controlled by a control circuit which receives as input the angular position of the first external structure (1) relative to the second structure.

[0072] Figure 11 shows the force curves during the relative movement of the first structure (1) with respect to the second structure (3) as a function of the different possible polarization states of the magnets (7a) and (7b) for the alternative shown in figure 10. To present these curves, the inventors propose to illustrate two states of magnetization of each of the magnets (7a and 7b), state 1 being the state corresponding to the polarization of the magnets (7a, 7b) in which the magnetic flux generated in their respective yokes (40, 41) is opposite to the magnetic flux generated by the magnet (5) in this same yoke, and state 2 being the state in which that flow is applied to the yokes (40, 41). Thus, curve (70) corresponds to the forces obtained when magnet (7a) is in state 1 and magnet (7b) is in state 2, generating a force of 36 notches over one complete revolution. Curve (73) corresponds to the forces obtained when magnet (7a) is in state 1 and magnet (7b) is in state 2, generating a force of 18 notches over one complete revolution. Curve (71) corresponds to the force obtained when the two magnets (7a and 7b) are in state 1, generating a superposition of both forces previously described at notches 36 and 18 over a complete rotation. Curve (72) corresponds to the force obtained when the two magnets (7a and 7b) are in state 2, generating no force during rotation.

[0073] Of course, the curves obtained are only illustrative of the possible forces and other profiles can be obtained by adjusting the amplitude of the magnetization of magnet (7a) relative to magnet (7b).

[0074] Active Stop Device The invention also relates to a stopping device which can be activated at any point of the relative movement.

[0075] Generally speaking, the stopping device comprises: a first structure (100) made of a ferromagnetic material; - a second structure (200) moving relative to said first structure (100), said second structure (200) comprising at least one ferromagnetic body (210), having at least one housing (220, 221) and supporting at least one coil (250) capable of changing the magnetization state of said ferromagnetic body (210); at least one braking element (310, 320) comprising a permanent magnet (350);

[0076] The housings (220, 221) are on opposite sides of the first structure (100) and together with the first structure (100) form a magnetic gap (300) in which the damping elements (310, 320) are housed, the position of the damping elements (310, 320) within the housings (220, 221) depending on the magnetization state of the ferromagnetic material (210).

[0077] It is specified that the damping elements (310, 320) are solid materials, except for the magnetorheological fluid, and require a complex structure, particularly with a sealed housing.

[0078] In an alternative embodiment, a first magnetization state of the ferromagnetic body (210) induces mechanical contact between one of the damping elements (310, 320) and the first structure (100), which damping element prevents a movement of the first structure (100) in a direction of movement according to one degree of freedom, the second magnetization state of the ferromagnetic material (210) induces mechanical contact of a complementary damping element (320, 310) with the first structure (100), said damping element preventing a movement of said first structure (100) in the opposite direction of movement according to the same degree of freedom; The third magnetization state of the ferromagnetic material (210) induces there to be no mechanical contact between the damping elements (310, 320) and the first structure (100), which is free to move according to this same degree of freedom.

[0079] In an alternative embodiment, the first magnetization state of the ferromagnetic material (210) induces mechanical contact of two damping elements (310, 320) with the first structure (100), said damping elements preventing the movement of said first structure (100) in both directions of movement having degrees of freedom; The second magnetization state of the ferromagnetic material (210) induces there to be no mechanical contact between the damping elements (310, 320) and the first structure (100), which is free to move according to this same degree of freedom.

[0080] Among various alternative embodiments, contact of the braking elements (310, 320) with the first magnetized structure (100) prevents movement of said first structure (100) by friction, by a hard stop, or by an elastic stop.

[0081] The magnets (350, 351) of the braking elements (310, 320) necessarily have a coercive force, typically 600 kA / m and in all cases greater than 100 kA / m. For their part, permanence is not really of concern. Thus, the whole range of magnets extending from ferrite to sintered neodymium magnets may be suitable, chosen as a function of the mechanical strength required by the magnet in question.

[0082] The first structure (100) is made of a ferromagnetic material to improve the circulation of the flow in the damping elements (310, 320) and to improve the contact between the damping elements and the first structure (100). However, this first structure (100) may be made of a non-magnetic material when the desired damping performance is lower, for example to reduce its weight.

[0083] First example of active stopping According to a first embodiment, we propose a monostable device in the free position.

[0084] In this embodiment, shown in Fig. 12a in a rotated version, the ferromagnetic body (210) is made of a soft ferromagnetic material that has zero magnetization in the absence of a current supply to the coil (250). The housings (220, 221) have an asymmetric partially cylindrical shape and are each capable of receiving a cylindrical damping element (310, 320).

[0085] The braking elements (310, 320) comprise cylindrical magnets (350, 351) that pass through and are fixed relative to the second structure (200) and have eccentric axial pivots (360, 361) that allow only one degree of freedom in the rotation of the magnets (350, 351) about the eccentric axial pivots (360, 361). Eccentric rotation in one direction allows the braking elements (310, 320) to come into contact with the first structure (100) or eccentric rotation in the opposite direction allows the braking elements (310, 320) to be inserted into their housings (220, 221).

[0086] When the braking elements (310, 320) are in contact with the first structure (100), a movement of the first structure (100) in one direction may result in blocking of the first structure (100) by abutment of the braking elements (310, 320) due to eccentric rotation. A movement of the first structure (100) following a movement in the opposite direction allows the release of the blocking by abutment, if necessary, and the remaining movement is only braked by the braking elements (310, 320).

[0087] The position of the damping elements (310, 320) within the housings (220, 221) depends not only on the magnetic field generated by the magnets (350, 351) of the damping elements (310, 320), but also on the magnetic state of the ferromagnetic body (210). In the example of Fig. 12a, the ferromagnetic body (210) can have three distinct magnetization states as a function of the current flowing through the coil (250): - Either there is no current passing through the coil and the magnetization state is zero; - or the coil passes a positive current greater than the threshold current, which results in a magnetization state called "positive magnetization"; or the coil has a current of the same intensity passing through it but flowing in the opposite direction, which results in a "negative magnetization" state.

[0088] The housing (220, 221) of the ferromagnetic body (210) is bounded by asymmetric pole tips (260, 261, 262, 263), which in the illustrated example are asymmetric and carefully dimensioned to provide a specific position of the braking element as a function of the magnetization state of the ferromagnetic body (210).

[0089] When the ferromagnetic body (210) is in a zero magnetization state, a force is exerted on the braking elements (310, 320) that attracts the braking elements (310, 320) into the housing, caused by the magnetic field generated by the magnets (350, 351) of the braking elements (310, 320) looping through the pole tips (260, 261, 262, 263) within the ferromagnetic body (210). When the ferromagnetic body (210) is in a positive or negative magnetization state, the magnetic field it generates loops back from one housing (220, 221) to the other housing, then exerts a force on the braking elements (310, 320) to align its magnetic field with the magnetic field of the ferromagnetic body (210).

[0090] Along the magnetization direction of the magnets (350, 351) or the position of the pivot (360, 361) in the eccentric axis direction, the damping element is in contact with the first structure (100) in the positive magnetization state of the ferromagnetic material (210) and is attracted into its housing (220, 221) in the case of negative magnetization, and vice versa.

[0091] Thus, as shown in FIG. 12a, if the two magnets (350 and 351) have opposite behavior when the magnetization state of the ferromagnetic material (210) is not zero, we obtain, in the case of positive magnetization, blocking of movement in a first direction by one of the braking elements (310, 320) and free movement in the opposite direction, and, in the case of negative magnetization, free movement without the first direction and blocking in the opposite direction by the second braking element (320, 310).

[0092] Figure 12b shows the torques obtained on the two braking elements (310, 320) around their pivot points as a function of the supply current to the coil (250) when the braking elements (310, 320) each allow blocking in the opposite direction, as explained in the previous paragraph. It should be noted that at zero power supply current, the two frictional parts (310, 320), each of them inserted in its housing (220, 221), have opposite torques that make it possible to obtain free rotation of the first structure (100) relative to the second structure (200).

[0093] However, this is not a limitation of the invention, and if the two magnets (350 and 351) have identical behavior as a function of the magnetization state of the ferromagnetic material (210), we obtain blocking in both directions for a given magnetization, and free movement for the opposite magnetization.

[0094] In a preferred embodiment, the first structure (100) has a portion made of a soft ferromagnetic material to facilitate looping of the magnetic flux generated by the ferromagnetic body (210) and therefore maximizing the force exerted on the damping elements (310, 320), although this is not a limitation of the invention.

[0095] Finally, this embodiment has a braking element (310) integrating a magnet (350) integrated in a ferrule (351), which is optional and may have several functions such as improving the coefficient of friction or improving the mechanical strength. Similarly, the rotational guidance of the friction element (310), here supported directly by the magnet (350), can be achieved by another integral part of the friction element (310) having other mechanical properties.

[0096] Modification of ferromagnetic material (210) An alternative embodiment of the ferromagnetic body is shown in Fig. 13a. This alternative embodiment differs from the previous one in that the ferromagnetic body (230) is not a monolithic body but an assembly of several ferromagnetic elements, and in that the stopping device has a stable stopping state, i.e. a state in which there is no power supply current to the coil (250). In this embodiment, the ferromagnetic body (210) comprises a permanent magnet (215) surrounded by a coil (250) and embedded between two magnetic flux conductors (211, 212) of soft ferromagnetic material each having a housing (220, 221).

[0097] The ferromagnetic body optionally incorporates a magnetically saturable isthmus (213) that directly connects the two magnetic flux conductors (211, 212).

[0098] The permanent magnet (215) has a low coercivity, i.e. a semi-permanent or AlNiCo type magnet material, typically with a permanence of 1.2 Tesla and a typical coercivity of 50 kA / m, in any case less than 100 kA / m. The magnetization direction is along the largest dimension of the permanent magnet (215). The low coercivity of the permanent magnet (215) is necessary in order to easily adjust the amplitude and direction of its magnetization by means of a coil located around it, which is done with limited energy and allows the use of the permanent magnet (215) in integrated devices without the use of powerful and expensive electronics. To adjust the polarity direction and / or amplitude of the magnetization of the low coercivity magnet, a current is applied to the coil (250), for example in the form of a direct current or an electric pulse provided by discharging a capacitor.

[0099] Depending on the amplitude and direction of the magnetization of the permanent magnet (250), the inventors can obtain in a stable manner, i.e., in the absence of current in the coil (250), the positive and negative magnetization states of the ferromagnetic material (210) described in the previous embodiment.

[0100] The isthmus (213) has a small cross section so as to allow direct looping of part of the magnetic flux of the permanent magnet (215). Direct looping is understood to mean a loop between the two poles of the magnet, a magnetic flux channeling, made integrally in the soft ferromagnetic part. The cross section of this isthmus (213) is intentionally limited so that the magnetic flux of the permanent magnet (250) can only be looped back up to a given magnetization level, which is, for example, 10 times lower than the saturation level of the permanent magnet (215). As long as the isthmus is not magnetically saturated, the ferromagnetic body (210) has a zero magnetization state, which makes it possible to extend the magnetization range of the permanent magnet (250) in which the ferromagnetic body (210) is in this state, in order to advantageously overcome the difficulty of obtaining a complete demagnetization of the permanent magnet (250).

[0101] Figure 13b shows the torque obtainable on the two braking elements (310, 320) as a function of the level of magnetization of the permanent magnet (215) when each of the braking elements (310, 320) allows blocking in one direction, as explained in the previous paragraph. The effect of the magnetic isthmus is shown by the presence of a torque plateau up to a certain amplitude of magnetization of the permanent magnet (215). It is noted that at low magnetization levels, the two friction parts (310, 320), each of them inserted in its housing (220, 221), have an opposite torque that allows obtaining free rotation of the first structure (100) relative to the second structure (200).

[0102] Alternative examples of braking elements (310, 320) An alternative embodiment of the damping elements is shown in Fig. 14. In this embodiment, the housing (220, 221) of the ferromagnetic body (210) has a notch shape and the pole tips (260, 261, 262, 263) are symmetrical. The damping elements (310, 320) then have a shape complementary to the housing (220, 221) in their proximal parts and engage more or less deeply with clearance, creating a sliding connection together. In their proximal parts, the damping elements (310, 320) have an asymmetric curved shape so as to abut each of the damping elements (310, 320) in only one direction when the damping elements (310, 320) are brought into contact with the first structure (100).

[0103] Alternative stopping device for braking element (310) An alternative embodiment of the stop is shown in Figure 15. This embodiment differs from the previous embodiment in that it has a linear relative displacement between the first structure (100) and the second structure (200) and in that it comprises only one braking element (310) located in a housing (220) defined by two pole tips (260, 261) extending the ferromagnetic body (210) on either side of the coil (250). Depending on the magnetization state of the ferromagnetic body (210), the braking element (310) either being attracted by the magnetic pole tip (260, 261) and being pushed by the second pole tip (261, 260), in case of positive magnetization this produces a stop in the direction of relative movement between the first structure (100) and the second abutment structure (200) of the friction part (310) and a rotation accompanied by friction in the opposite direction; or attracted by a first pole tip (260, 261) and pushed back by a second pole tip, in case of negative magnetization this creates a stop in the opposite relative movement direction of the first and second structures, or in the case of zero magnetization, it is attracted by both pole tips (260, 261), which leaves a relative displacement between the first and second structures in both directions.

[0104] Of course, this stationary version is not limited to linear movement and can be adapted by one skilled in the art for use with rotational devices.

[0105] Alternative Index Stop Embodiments An alternative embodiment of the stop is shown in Figures 16a, 16b and 17. This embodiment differs from the embodiment shown in Figure 13a in that the first structure (100) is located inside the second structure and has periodically spaced notches (110) that can accommodate braking elements (310).

[0106] These embodiments have the particularity of a central through recess (305), making it possible to produce a cylindrical housing with a rotating ring or a button surrounding an instrument with a cylindrical body, for example a watch.

[0107] They also make it possible to place within or behind the central recess (305) a display screen for displaying indications representing the state of the buttons or the state of the functions controlled by the buttons.

[0108] The stop is no longer made by abutment, but is generated by fitting the braking element (310) into one of the notches (110). This embodiment also differs from the previous embodiment in that it does not make it possible to obtain a stop at any relative position of the first structure (100) with respect to the second structure (200), but at an indexed position corresponding to the periodicity of the notches (110). This embodiment also differs in that the braking element (310) systematically performs the stop in both directions of relative movement of said first and second structures. Finally, this embodiment differs from the previous embodiment in that the different magnetic states of the ferromagnetic body (210) are obtained by cooperation of two magnets (215, 216) and a coil (250) that at least partially surrounds the magnet (215). The magnet (215) has a low coercive force of less than 100 kA / m so that its amplitude and its magnetization direction can be easily adjusted by supplying the coil (250) with electricity. The second magnet (216) has a strong coercive force of greater than 100 kA / m, so that its magnetization is not altered when electricity is supplied to the coil (250).

[0109] Figure 16a shows this stopping device in a ferromagnetic (201) magnetic state that allows free relative rotation of both structures (100, 200), and Figure 16b has the stopping device in a ferromagnetic (201) magnetic state that allows the brake element (310) to engage with the notch (110) of the first structure.

[0110] Finally, even though the device has indexed stop positions, the magnetic state of the ferromagnetic material (210) can be changed at any relative position of the first structure (100) and the second structure (200), resulting in friction of the braking element (310) on the outer periphery of the first structure (100) until the braking element (310) engages with the notch (110).

[0111] Figure 17 shows the integration of this stop alternative in an indexing device according to the invention. A first structure (100) then has teeth (2) which cooperate with teeth (11) defining periodic notches (110) of a second structure (200). This second structure then has a low coercivity third magnet (7) partially surrounded by a second coil (8), the magnetization state of the second structure being: - a periodic variation mode of forces during the relative movement of the two structures (100, 200); -Free rotation mode during relative movement of the two structures; - a stop mode in which the two structures can no longer move relative to each other; and - a stop mode in which the supply of one or the other of the coils (8, 250) can be modified to produce

[0112] Example Applications The haptic control device according to the invention is intended in particular to complement a display screen (304), an example of which is shown in Fig. 18. A toothed structure (11) is associated with the screen (304), the structure (100) being driven by a peripheral ring (308). A recessed central portion (305) of the control device (307) allows a screen (306) to be accommodated therein in order to display information, for example the volume level, in the center of the device. In an alternative version, the toothed structure is directly bonded to the surface of the screen (304), the screen (306) being the part of the screen (304) that is visible through the recessed central portion (305) of the control device.

[0113] The present application makes it possible to create dynamic man-machine interfaces (MMIs) that combine the flexibility of a display screen, and in particular a touch screen, with the precision of mechanical buttons, persistent functional interaction between the display and the various control modes, tactility through the screen, or tactility through the control device.

[0114] This solution is particularly suitable for centralized MMIs in automobiles, e.g. electric vehicles, which control a large number of functions related to vehicle operation, comfort and infotainment functions. Certain functions, especially techniques, are important, e.g. driving modes (sport, economy, etc.) and simply sliding a finger on a touch screen does not give a satisfying sensation. Therefore, the haptic feedback of the device according to the invention is more appropriate.

[0115] For other functions, such as temperature regulation, it is desirable to be able to quickly reach the fine adjustment region, in which case the indexing flexibility allowed by the present invention allows for dynamic adjustment of rotational pitch.

[0116] A similar application relates to domestic appliances, for example glass ceramic or induction cooking plates, where controlling the indexing of control buttons arranged on the plate is advantageously visible through a central recess of textual or graphic information, making it possible to extend the control of the plate.

[0117] Another application is in the control of audiovisual equipment, allowing the same buttons with controlled indexing to be used to control sound level, channel or station selection.

[0118] Another function concerns recording the most frequent positions for each of the usage modes in order to control the operating modes corresponding to the user's personalized habits. To this end, the computer periodically records the state of the control device, in particular the energized state of the coil (250) and the positions of the control buttons, in order to determine the frequent combinations.

[0119] Alternative Embodiments According to an alternative embodiment, the electrical signal delivered by the position sensor (10) is derived to provide a signal representative of the speed of movement of the control member. The signal thus processed makes it possible to dynamically adjust the forces as a function of the dynamics of the member's motion, for example by decreasing the pitch of the notches to increase their effect during slower speeds of motion in order to improve the accuracy of the motion, and conversely by increasing the pitch of the notches to decrease their amplitude during faster speeds of motion.

Claims

Claim 1 A control device, comprising at least one permanent magnet (5, 7; 7a, 7b; 350, 351), and a mechanically guided member, comprising a. a first ferromagnetic structure (1, 100), and b. a second ferromagnetic structure (3; 200) provided with at least one electric coil (8, 9; 250), the electric coil (8, 9; 250) being configured to change the magnetization state of the second ferromagnetic structure (3, 200) according to the direction and amplitude of a current flowing through the electric coil (8, 9; 250), and enabling relative movement between the second ferromagnetic structure (3, 200) and the first ferromagnetic structure (1, 100), wherein the control device further comprises position detection means (10) for detecting the relative position of the first ferromagnetic structure and the second ferromagnetic structure, and a control circuit for controlling a supply current to the electric coil (8, 9; 250) that varies as a function of a signal sent by the position detection means (10). The control device is characterized by the above. Claim 2 The control device according to claim 1, wherein the control circuit controls the supply current of the electric coil (8, 9; 250) as a function of a signal representing the relative position of the first ferromagnetic structure (1, 100) and the second ferromagnetic structure (3, 200). Claim 3 The control device according to claim 1, wherein the control circuit controls the supply current of the electric coil (8, 9; 250) as a function of a signal representing the speed of the relative movement of the first ferromagnetic structure (1, 100) and the second ferromagnetic structure (3, 200). Claim 4 Magnetic detection means for magnetically detecting the relative movement by means of a magnetic interaction between the first ferromagnetic structure (1) and the second ferromagnetic structure (3), wherein the at least one permanent magnet (5) is integral with the second ferromagnetic structure (3), the at least one electric coil (8, 9) for controlling the magnetization state of the second ferromagnetic structure (3) through the change in the magnetization state of the permanent magnet (5) in the direction and amplitude of the current flowing through the electric coil (8, 9), and the permanent magnet (5) is at least partially surrounded by the at least one electric coil (8, 9), and the magnetic detection means is adjusted by the magnetization state of the second ferromagnetic structure (3). The control device is characterized by the above. Claim 5 The control device according to claim 4, characterized in that the first ferromagnetic structure (1) and the second ferromagnetic structure (3) each have a plurality of radial teeth (2, 11) that cooperate to generate the magnetic determination means.

6. The control device according to claim 1, further comprising means for selecting a variable force mode from a plurality of predetermined variable force modes and delivering a signal used by the control circuit to change the supply mode of the electric coil (250).

7. The control device according to claim 6, further comprising an interface with a controlled device that delivers a signal used by the control circuit to change the supply mode of the electric coil (250).

8. The control device according to claim 1, comprising a position sensor (12) capable of measuring the position of the first ferromagnetic structure (1) to provide the supply current of the electric coil (250) to the control circuit, wherein the input signal represents the relative positions of the first ferromagnetic structure (1) and the second ferromagnetic structure (3).

9. The at least one permanent magnet is a first magnet (7) and a second magnet (5), The control device according to claim 1, characterized in that the first ferromagnetic structure (1) and the second ferromagnetic structure (3) have teeth (2), and the second ferromagnetic structure (3) consists of two toothed semi-tubular parts (4a, 4b) connected on one hand by the second magnet (5) and on the other hand by the first magnet (7).

10. The at least one permanent magnet is a first magnet (7) and a second magnet (5), The control device according to claim 1, characterized in that the magnetization directions of the first and second magnets (5, 7) are the same.

11. The magnetization state of the second ferromagnetic structure (3, 200) is changed at the relative positions of the first and second ferromagnetic structures located within a plus or minus 25% interval of the period of determination of the magnetic determination means, the interval being centered on the stable equilibrium position of the magnetic determination means. The control device according to claim 4.

12. The magnetization state of the second ferromagnetic structure (3, 200) is changed at a relative position of the first ferromagnetic structure and the second ferromagnetic structure located within an interval of plus or minus 10% of the period of the determination by the magnetic determination means, and the interval is centered on the stable equilibrium position of the magnetic determination means. The control device according to claim 4, characterized in that.

13. An active stop part, the first ferromagnetic structure (100) that moves relative to the second ferromagnetic structure (200), At least one braking element (310), The relative movement between the first ferromagnetic structure (100) and the second ferromagnetic structure (200), a. The braking element (310), b. The second ferromagnetic structure (200), which includes a ferromagnetic body (210) at least partially surrounded by the electric coil (250), and the electric supply of the electric coil (250) changes the magnetization of the ferromagnetic body (210). An active stop part comprising at least one braking element (310) that is obstructed by the magnetic interaction between the second ferromagnetic structure (200) and the second ferromagnetic structure (200). The magnetization state of the ferromagnetic body (210) adjusts the braking force between the first ferromagnetic structure (100) and the second ferromagnetic structure (200). The control device according to claim 1, characterized in that.

14. The control device according to claim 13, characterized in that the braking element (310) can adjust the braking force between the first ferromagnetic structure (100) and the second ferromagnetic structure (200) in a single direction of the relative movement.

15. The control device according to claim 13, characterized in that the braking element (310) can adjust the braking force between the first ferromagnetic structure (100) and the second ferromagnetic structure (200) in both directions of the relative movement.

16. The ferromagnetic body (210) is made of a soft ferromagnetic material whose magnetization is zero when the supply current of the electric coil (250) does not exist, and the ferromagnetic body (210) has a partially cylindrical housing (220, 221). The control device according to any one of claims 13 to 15, characterized in that each can receive a cylindrical braking element (310, 320).

17. The control device according to claim 13, characterized in that the braking elements (310, 320) are articulated to the eccentric shaft, and by moving one of the braking elements (310, 320) in one direction, the braking element (310, 320) contacts the first ferromagnetic structure (100), or by moving it in the opposite direction, the braking element (310, 320) retracts into its housing (220, 221).

18. The control device according to claim 13, characterized in that when the braking element (310, 320) is in contact with the first ferromagnetic structure (100), the relative movement of the first ferromagnetic structure (100) in one direction causes the first ferromagnetic structure (100) to be blocked by the contact due to the eccentric rotation of the braking element (310, 320).

19. The braking element (310) prevents the relative movement between the first ferromagnetic structure (100) and the second ferromagnetic structure (200) by a. the magnetic interaction between the braking element (310) and b. the first ferromagnetic structure (100) and c. the second ferromagnetic structure (200). The control device according to claim 13 is characterized by this.

20. The control device according to claim 13 is provided with means for magnetic determination of the relative movement between the first ferromagnetic structure (100) and the second ferromagnetic structure (200). The determination means is directly integrated into the first ferromagnetic structure (100) and the second ferromagnetic structure (200), or is made using two additional ferromagnetic structures (1, 3). One of the two additional ferromagnetic structures (1, 3) is integral with the first ferromagnetic structure (100) or the second ferromagnetic structure (200), and the other of the two additional ferromagnetic structures (1, 3) is integral with the other of the first ferromagnetic structure (100) or the second ferromagnetic structure (200).

21. The control device according to claim 13, characterized in that the ferromagnetic body (210) has a permanent magnet (215) at least partially surrounded by the electric coil (250), and the amplitude of the magnetization of the permanent magnet (215) is adjusted by the electric coil (250).

22. The control device according to claim 1, characterized in that the control of the electric coil (250) is controlled by a computer associated with a memory that periodically records the state of the control device in order to determine the most frequent state.

23. A man-machine interface comprising a display screen, further comprising at least one control device having the characteristic part according to claim 1, disposed on the visual surface of the display screen.

24. The man-machine interface according to claim 23, characterized in that the control device is a fovea (305), and information determined as a function of the magnetization state of the control device is displayed in a screen zone disposed behind the fovea (305).

25. An actuator comprising a module for driving an output member, further comprising a control device having the characteristic part according to claim 1, coupled to the output member.

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