Incremental magnetic encoder

Abstract

Incremental Magnetic Encoder The present invention relates to an incremental magnetic encoder (10) comprising a fixed body and a moving body. One of the bodies, referred to as the first body (21), comprises: - a first toothed component extending along a longitudinal direction and a circumferential direction, one of said directions corresponding to a first encoding direction; the other body, referred to as the second body (22), comprises: - a second toothed component defining a tooth made of magnetic or ferromagnetic material and arranged opposite teeth of the first toothed component; - a pair of magnetic coils configured to measure each change in inductance between the first toothed component and the second toothed component, to quantify each movement of the moving body along the first encoding direction. Figure for the abstract: Figure 2

Description

Title of the invention: Incremental magnetic encoder FIELD OF INVENTION

[0001] The present invention relates to an incremental magnetic encoder.

[0002] More particularly, the present invention relates to an encoder capable of providing binary logic signals representing increments of the relative position of two elements of the encoder, the two elements being movable relative to each other. Advantageously, such an encoder is applicable in the aeronautical field, for example in an aircraft cockpit.

[0003] Typically, in an application for aeronautical equipment, an angular and / or linear encoder can be used to indicate to an autopilot computer an altitude or speed setpoint that the operator selects by pressing a control button on the encoder. The reliability of the encoder and the information it provides is therefore an essential element of the encoder. The typical requirements for an aeronautical encoder may include one or more of the following: compactness, the ability to perform multiple rotations and / or linear travel, incrementing and detenting capabilities, etc. In order to be certified, the aeronautical encoder must also be able to meet high DAL (Design Assurance Level) safety standards, particularly DAL A.

[0004] In particular, with regard to compactness, an encoder typically has a control button with a diameter between 10 and 100 mm and a length between 5 and 50 mm (typically 0.16 mm x 1.16 mm) and a body with a diameter between 10 and 100 mm and a length between 5 and 100 mm (typically 0.25 mm x 1.50 mm) concealed behind the mounting panel or fixed in front of it. In the latter case, the button encompasses the encoder body, which is fixed to the panel, and allows it to be placed around, or even slightly overlapping, a monitor or screen.

[0005] With regard to the incrementing capability, each notch (or step) constitutes an increment of one unit of rotation or translation. The angular or linear resolution is defined per notch (or step). The number of steps per revolution is on the order of 1 to 32 steps (typically 12 steps). The number of steps in translation is from 1 to 10 notches (typically 1 notch in each direction to obtain a "push / pull" button with a stable state between the two notches).

[0006] To detect the direction of rotational and / or translational movement, the encoder generally has at least two detectors (one for rotation and one for translation) physically offset from each other (typically by an odd number of quarter steps). These two detectors allow the rotational and / or translational movement to be encoded using two bits. Thus, the encoding produces the successive values The following values ​​are used: 00, 01, 11, 10 when the encoder rotates and / or translates in one direction, and the following successive values: 00, 10, 11, 01 when the encoder rotates and / or translates in the opposite direction. It is therefore possible to determine not only the occurrence of a rotational and / or translational increment (a change of state in one of the bits) but also the direction of rotation (by comparing a detected state with the immediately preceding state).

[0007] Regarding the detenting capacity of the encoders, the passage of the encoded detent generally results in tactile feedback that an operator must feel when maneuvering the device. The angular detenting torque can, for example, be on the order of 1 to 700 mN.m (typically 12 mN.m) and the linear detenting force on the order of 0.5 to 20 N (typically 6 N).

[0008] The most complex encoders have rotational and translational encoding and detenting. Rotational encoding and detenting must not be blocked by translational encoding and detenting. In this case, rotational and translational detection and detenting must be able to be used simultaneously without loss of performance. For example, to enter a speed, the driver must simultaneously push the encoder button and turn it to the desired value.

[0009] Finally, in certain cases, to secure the encoder and in particular to guarantee its DAL security level (for example DAL A), the detection (or encoding) functions are at least doubled. STATE OF THE ART

[0010] To meet the aforementioned needs, the encoders used in aeronautical applications are often based on opto-mechanical solutions (optical detection and mechanical detenting) or electromechanical solutions (detection by electrical contact and mechanical detenting) and sometimes magneto-mechanical solutions (magnetic detection and mechanical detenting) or opto-magnetic solutions or even purely magnetic solutions.

[0011] For example, opto-mechanical encoders are described in documents FR 2937129 and FR 2954491. According to these documents, rotational and / or translational detection (encoding) is performed by an optical encoder, while maintaining a stable position (ratcheting) is ensured mechanically by at least one ball pressurized by a spring on a ball track (or cam). Even though these recent innovations meet the needs described above and aim to simplify their implementation, these opto-mechanical and electromechanical encoders remain complex assemblies made up of numerous high-precision parts.

[0012] More generally, current mechanically driven solutions generate friction (e.g., ball against cam) and wear, which limits the lifespan of the device, particularly when plastic parts are used. In encoders In electromechanical systems, detection and detenting are sometimes linked by at least one common mechanical part that serves both as a click and as a detection mechanism via an electrical contact. This contact is often subject to wear and fretting corrosion, thus limiting the device's lifespan. Furthermore, in optomechanical and sometimes electromechanical devices, detection and detenting are decoupled, meaning they result from different solutions and / or phenomena and are physically separated. This decoupling increases the number of parts and, consequently, the risk of misalignment between detection and detenting. In the case of complex and secure encoders, the number of parts is even greater. To ensure good performance and reliability, modern complex encoders require high-precision, and therefore more expensive, components.

[0013] We also know of document FR 2370350 which describes a rotary magnetic encoder with moving magnets in which the detenting and encoding are based on the magnetic phenomenon. However, the encoder in this document is only rotary and uses moving magnets which are exposed to risks of friction and jamming.

[0014] In summary, electromechanical solutions present the highest risk of fatigue, both in the detenting and encoding stages, because they generate the most friction. Furthermore, the electrical encoding is susceptible to fretting corrosion. These drawbacks reduce reliability and limit the device's lifespan.

[0015] Opto-mechanical and magneto-mechanical solutions retain the risk of fatigue at the level of the mechanical notching.

[0016] Opto-magnetic solutions use different contactless phenomena. These solutions are more cumbersome if a more complex (example: rotary encoder with "push / pull") and secure encoder is desired.

[0017] French patent FR 3135791 is now known, proposing a purely magnetic solution for implementing coding along one of the chosen directions, for example, the direction of translation and the direction of rotation, while ensuring detenting along the same direction. According to this patent, the coding and detenting are created by the same magnetic effect between the moving and fixed bodies. Thus, this patent resolves all the aforementioned problems. However, the solution proposed in this patent can still be improved, particularly in terms of size and reliability. Summary of the invention

[0018] The present invention aims to provide an incremental encoder that meets all the aforementioned needs, while improving the solution proposed in particular by document FR 3135791, especially in terms of size and reliability.

[0019] To this end, the invention relates to an incremental magnetic encoder defining an encoder axis and comprising a fixed body and a movable body relative to the fixed body along at least one first encoding direction;

[0020] one of the bodies, called the first body, comprising:

[0021] - a first toothed component extending along a longitudinal direction coincident with the encoder axis and a circumferential direction perpendicular to the longitudinal direction, one of said directions corresponding to the first coding direction, the first toothed component defining a plurality of teeth made of magnetic or ferromagnetic material and arranged according to the first coding direction;

[0022] the other body, called the second body, comprising:

[0023] - a second toothed component extending along the longitudinal direction and the circumferential direction, the second toothed component defining a tooth made of magnetic or ferromagnetic material and arranged opposite the teeth of the first toothed component during each movement of the moving body along the first coding direction;

[0024] - at least one pair of magnetic coils configured to measure each variation of inductance between the first toothed component and the second toothed component, to quantify each movement of the moving body according to the first coding direction.

[0025] Equipped with these features, the encoder according to the invention makes it possible to implement encoding along at least one of the chosen directions, for example, the direction of translation and the direction of rotation, without the use of a specific sensor. Indeed, according to the invention, the use of teeth made of magnetic or ferromagnetic material makes it possible to vary the inductance during the movement of the moving body relative to the fixed body. This variation is detectable by the magnetic coils, which thus perform the function of the magnetic sensors conventionally used in encoders operating on the magnetic effect. The magnetic coils can also be used to perform an additional function, such as a torque and / or detent force. Thus, the number and size of the internal components of the encoder can be significantly reduced.

[0026] Furthermore, the respective arrangement of the moving and fixed bodies can be chosen so as to minimize their mechanical contact. For example, the detailed elements of the fixed and moving bodies described above have no mechanical contact with each other. Thus, these elements operate without friction and without premature mechanical wear. This ensures the encoder's reliability in use and significantly extends its lifespan, even when plastic parts are used. Furthermore, these components are limited in number, allowing for easy placement within their respective housings. This makes encoder assembly particularly simple and reduces the risk of jamming or misalignment between different parts.

[0027] According to other advantageous embodiments of the invention, the magnetic encoder comprises one or more of the following features, taken individually or in all technically possible combinations:

[0028] - the teeth of the first toothed component are arranged according to the first coding direction according to a constant step;

[0029] - the first coding direction corresponds to the circumferential direction;

[0030] - the second toothed component comprises a plurality of teeth arranged according to the circumferential direction in relation to the teeth of the first toothed component in a synchronous or out-of-phase manner;

[0031] - the moving body is mobile relative to the fixed body according in addition to a second coding direction perpendicular to the first coding direction;

[0032] - the first toothed component further defines a plurality of teeth made of magnetic or ferromagnetic material and arranged according to the second coding direction;

[0033] - the second toothed component defines a tooth made of magnetic material or ferromagnetic and arranged opposite the teeth of the first toothed component during each movement of the moving body along the second coding direction;

[0034] - at least one pair of magnetic coils is configured to measure each variation of inductance between the first toothed component and the second toothed component, to quantify each movement of the moving body according to the second coding direction;

[0035] - wherein the first toothed component comprises a plurality of gears arranged along the encoder axis;

[0036] - the gears are spaced apart to form a plurality of teeth according to the encoder axis;

[0037] - the second toothed component comprises at least one toothed wheel arranged in coaxially with at least one toothed wheel of the first toothed component at least in a rest position of the encoder;

[0038] - the encoder comprises a plurality of magnetic coils arranged in such a way circumferential on the toothed wheel of the second toothed component;

[0039] - each magnetic coil extends around a pair of teeth formed by the wheel toothed of the second toothed component;

[0040] - the second toothed component comprises at least two toothed wheels arranged along the encoder axis;

[0041] - at least one magnetic coil is disposed between said toothed wheels of the second toothed component and extends around the encoder axis;

[0042] - the encoder comprising at least two first toothed components arranged along the encoder axis and at least two second toothed components arranged coaxially with the first toothed components;

[0043] - each first toothed component comprises at least one toothed wheel;

[0044] - the gears corresponding to primary components different ones are out of phase by a predetermined angle;

[0045] - the magnetic coils are configured to be energized during the operation of the encoder, to create a torque or a notching force between the first toothed component and the second toothed component during each respective movement of these components along the first coding direction and / or a second coding direction;

[0046] - the magnetic coils are configured to be powered according to a context of use of the encoder or to generate haptic feedback;

[0047] - the number of notches along a coding direction is determined by the number of teeth of the first toothed component or of the second toothed component according to this coding direction;

[0048] - the encoder further comprises one or more permanent magnets arranged to strengthen the torque and / or the engagement force and / or generate a torque and / or a return force. DESCRIPTION OF THE FIGURES

[0049] These features and advantages of the invention will become apparent from the following description, given solely by way of example and not limitation, and made with reference to the accompanying drawings, in which: - [Fig.1] [Fig.1] is a schematic perspective view of a magnetic encoder according to a first embodiment of the invention, the encoder being partially fixed behind a panel forming a dashboard; - [Fig.2] [Fig.2] is an exploded perspective view of the encoder of [Fig.1], the encoder comprising a fixed body including a stator and a moving body including a rotor; - [Fig.3] [Fig.3] presents a partial view of a section along the longitudinal plane III of [Fig.1]; - [Fig.4] [Fig.4] is an exploded perspective view of the stator and rotor of [Fig.2]; - [Fig.5] [Fig.6] Figures 5 and 6 are detailed views of the rotor of [Fig.2]; - [Fig.7] [Fig.7] is a perspective view of an element of the stator of [Fig.2]; - [Fig.8] [Fig.8] is a diagram explaining the operation of the element in [Fig.7]; - [Fig.9] [Fig.9] is a view analogous to that of [Fig.3] showing optional features of the encoder of [Fig.1]; - [Fig. 10] [Fig. 10] is a view similar to that of [Fig. 3] showing a magnetic encoder according to a second embodiment of the invention, the encoder comprising a fixed body including a stator and a moving body including a rotor; - [Fig. 11] [Fig. 11] is an exploded perspective view of the stator and rotor of [Fig. 10]; and - [Fig. 12] [Fig. 13] Figures 12 and 13 are detailed views of the rotor of [Fig. 10]; - [Fig. 14] [Fig. 14] is a perspective view of an element of the stator of [Fig. 10]; - [Fig. 15] [Fig. 15] is a view analogous to that of [Fig. 3] showing optional features of the encoder of [Fig. 10]; and - [Fig. 16] [Fig. 16] is a schematic view of a pair of gear wheels according to an embodiment other than those described in relation to the previous figures. DETAILED DESCRIPTION OF THE INVENTION

[0050] Figure 1 illustrates an incremental magnetic encoder 10 according to a first embodiment of the invention. Preferably, the encoder 10 is mounted in a cockpit for piloting an aircraft.

[0051] The term "aircraft" means any flying machine, such as an airplane, helicopter, or drone, for example. Such an aircraft can be piloted directly from within it. In such a case, the cockpit is advantageously located inside the aircraft. According to another embodiment, such an aircraft is remotely controlled. In such a case, the cockpit is located at a distance from the aircraft and includes, for example, a ground station. In all cases, the aircraft is configured to be piloted by an operator, for example, a pilot, from the cockpit located inside the aircraft.

[0052] According to the invention, the encoder 10 allows the operator to control at least one avionics function. For example, such an encoder 10 can be used by the operator to control an avionics system and is part of a control system for such an avionics system. Alternatively, the encoder 10 is part of a control system for several avionics systems. For example, the encoder 10 according to the invention is part of a system called a "Flight Control Unit" (FCU) or "Integrated Standby Instrument System" (ISIS) or "Closer Control Device" (CCD) or "Keyboard Cursor Control Device" (KCCD), etc.

[0053] In the example of [Fig. 1], the encoder 10 is partially integrated into a panel 12. This panel 12 forms, for example, an instrument panel in the aircraft cockpit for one of the aforementioned control systems. In the example of [Fig. 1], the encoder 10 is arranged partly in the front portion 12A of the panel 12 and partly in the rear portion 12B of this panel 12. In particular, in the example of [Fig. 1], the front portion 12A of the panel 12 faces the operator, while the rear portion 12B of this panel faces the interior of the instrument panel. Of course, other arrangements of the encoder 10 relative to the panel 12 or to any other mounting means are also possible. In particular, according to another possible embodiment (not illustrated), the encoder 10 is disposed entirely in the front part 12A of the panel 12.

[0054] With reference to [Fig.2], the encoder 10 comprises a movable body 21, also called in the example of this figure first body, and a fixed body 22, also called in the example of this figure second body.

[0055] The movable body 21 includes a button 31 and a rotor 33.

[0056] The button 31 protrudes from the panel 12 and is arranged in the front portion 12A of this panel 12. The button 31 is movable in translation along an X-axis encoder and in rotation about the X-axis encoder. More specifically, the button 31 is movable in a first coding direction Cl, which in this example corresponds to the direction of rotation about the X-axis encoder, and a second coding direction C2, which in this example corresponds to the direction of translation along the X-axis encoder. Advantageously, the button 31 is movable in each direction along each coding direction Cl, C2. In particular, in the direction of rotation, the button 31 is movable in rotation in both clockwise and counterclockwise directions, and in the direction of translation, the button 31 is movable towards the instrument panel and towards the operator. Advantageously, the button 31 defines in particular a button surface 34 which is intended to be oriented towards the operator.This surface 34 therefore represents an external surface of the button 31 which is visible to the operator and can be grasped by the operator.

[0057] The rotor 33 extends along the encoder axis X so as to form a fixed connection at one of its ends with the button 31. Thus, just like the button 31, The rotor 33 is movable along the first coding direction Cl and along the second coding direction C2 in each of the aforementioned directions of movement. The rotor 33 receives functional internal elements from the moving body 21, which will be explained in more detail later.

[0058] The fixed body 22 comprises a stator 41 and a flange 43.

[0059] The flange 43 is, for example, disposed in a hole 35 through the panel 12 and allows support for the button 31 and the rotor 33. In the example of [Fig.2], the flange 43 is fixed to the panel 12 while remaining in the rear part 12B of it, using for example screws accessible from the front part 12B of the panel 12.

[0060] The stator 41 receives and / or includes functional internal elements of the fixed body 22 that are intended to cooperate with the functional internal elements of the moving body 21, as will be explained in more detail later. In particular, and as will become apparent later, the functional internal elements of the fixed body 22 are held at a distance from those of the moving body 21 by the stator 41. To achieve this, the stator 41 is configured to receive at least partially the rotor 33 with the functional internal elements of the moving body 21 carried by this rotor 33. According to another embodiment (not illustrated), the rotor 33 is configured to receive at least partially the stator 41 with the corresponding functional internal elements. This mode is usable, for example, when the encoder 10 is located entirely within the front portion 12A of the panel 12.

[0061] The stator 41 is, for example, connected to the moving body 21 via a movable linkage in each encoding direction. This linkage can, for example, be formed at each end of the rotor 33 and have plain bearings, for example polymer bearings or sintered bronze bearings. These bearings preferably have flanges to serve as mechanical stops in both directions of movement of the rotor 33 around the encoder axis X. In another example, these bearings are rolling element bearings such as ball bushings. Figure 3 shows, in particular, the bearings 37 connecting the rotor 33 to the second body 22. In the example in this figure, the bearings 37 connect one end of the rotor 33 directly to the stator 41 and the other end of the rotor 33 to the stator 41 via the flange 43. In this example, the flange 43 is configured to cooperate with the stator 41 in order to fix it to the panel 12.The stator 41 can be made up of several parts stacked along the X-axis of the encoder.

[0062] Furthermore, a cover can be provided to protect all the components of the encoder 10 which are arranged in the rear part 12B of the panel 12

[0063] In the example of Figure 4 illustrating in more detail the functional internal elements of the fixed body 22 and the moving body 21, the rotor 33 has for example a cylindrical shaft 45 extending along the encoder axis X.

[0064] With reference to Figures 4 to 6, the internal functional elements of the moving body 21 comprise at least two rotor toothed components 51, 52. Each of these components 51, 52 is fixed to the shaft 45 along the encoder axis X and remains spaced from the other component 51, 52 by a distance d. In some embodiments, the rotor toothed components 51, 52 are fixed to the shaft 45 by means of a spacer 53 and a circlip or retaining ring. The anti-rotation of the components 51, 52 can be ensured by keys or pins. The shaft 45 and the spacer 53 are preferably made of a non-magnetic material (e.g., bronze alloy) to avoid magnetic leakage.

[0065] Each of the rotor toothed components 51, 52 is made of a magnetic or ferromagnetic material and comprises a plurality of gears 57 arranged along the encoder axis X. The gears 57 of each rotor toothed component 51, 52 are, for example, spaced along this axis X by the same distance, for example substantially equal to or less than the spacing distance d between the rotor toothed components 51, 52. All the gears 57, for example, have substantially the same thickness. Thus, along the X encoder axis, the gear wheels 57 have a toothed longitudinal profile defined by a pitch PI characterized by the thickness of the wheels 57, the spacing between these wheels 57 and the height of each tooth in a longitudinal section passing through the center of these wheels 57. Advantageously, the wheels 57 have the same height of each tooth in each longitudinal section passing through the center of these wheels 57.

[0066] Each gear 57 also forms a plurality of teeth arranged circumferentially outwards from the gear, for example, with the same angular pitch P2. Each gear 57 comprises, for example, the same number of teeth arranged circumferentially. These teeth are, for example, of the same dimensions. Thus, each gear 57 forms the same circumferential toothed profile. In the example of [Fig. 6], the number of teeth on each gear 57 is 32. This forms an angular pitch P2 of 11.25°.

[0067] In the example of [Fig.5], each rotor toothed component 51, 52 comprises three gear wheels 57. Thus, each rotor toothed component 51, 52 comprises a central wheel and a pair of peripheral wheels. Furthermore, within the same rotor toothed component 51, 52, the gears 57 are advantageously arranged synchronously, i.e., in phase, along the encoder axis X. In other words, in this case, each tooth of a gear 57 is aligned along the encoder axis X with another tooth of an adjacent gear 57 within the same rotor toothed component 51, 52. Conversely, between the different rotor toothed components 51, 52, the gears 57 are phase-shifted by a predetermined phase angle θ, as can be seen in [Fig. 6]. This predetermined angle θ is for example a proportion of the angular step P2. This proportion is for example equal to Thus, in the example of [Fig.6], this angle q> can be approximately equal to 2.8125°.

[0068] Returning to the description of [Fig. 4], the internal functional elements of the fixed body 22 comprise a stator toothed component 61, 62 for each rotor toothed component 51, 52 and fastening means 64 for fixing the stator toothed components 61, 62 to form the stator 41 as explained previously. In particular, the fastening means 64 make it possible to fix each of the stator toothed components 61, 62 in a fixed position opposite its corresponding rotor toothed component 51, 52, at least in a rest position of the encoder 10.

[0069] In the example of [Fig.4], the fixing means 64 include a spacing flange 67 allowing the stator toothed components 61, 62 to be separated along the encoder axis X according for example to the distance d and one or more fixing flanges 68 analogous to the flange 43 as described previously. The fastening means 64 further include a plurality of longitudinal screws (or threaded rods with nuts) 69 extending along the encoder axis X for assembling the mounting flanges 68, the spacer flange 67 and each of the stator toothed components 61, 62 along the encoder axis X. For this purpose, each flange 67, 68 and each stator toothed component 61, 62 may define opposing holes allowing the passage of one of the longitudinal screws 69. The mounting flanges 68 may be made of a non-magnetic material such as aluminum or plastic.The flange 67 is advantageously made of a magnetic or ferromagnetic material because the magnetic flux, identified in [Fig.3], passes through it to go from part 61 to part 62. Of course, the fastening means 64 can be implemented in any other suitable form.

[0070] The stator toothed components 61, 62 are, for example, substantially similar to each other. The passage of the screws or threaded rods 69 through the corresponding holes thus ensures alignment of the stator teeth 61, 62. Therefore, hereafter, only the stator toothed component 61 will be described in detail with reference to [Fig. 7].

[0071] Thus, as illustrated on the left side of [Fig. 7], the stator gear component 61 comprises a central gear 71 and a pair of peripheral gears 72 adjacent to the opposite sides of the central gear 71 along the encoder axis X. As can be seen on the right side of [Fig. 7], the central gear 71 defines a plurality of teeth 74 arranged towards the inside of this gear 71. The teeth 74 are grouped to form pairs. These pairs are arranged circumferentially and are spaced from each other uniformly by the same angular pitch P3 along the circumferential direction. In particular, in the example of the [Fig. 7], the central wheel 71 defines 8 pairs of teeth 74 arranged homogeneously along the circumferential direction. Each pair of teeth 74 is formed of two teeth extending along the encoder axis X and separated from each other by a cavity 75 also extending along the encoder axis X. Thus, the central wheel 71 defines a circumferential toothed profile.

[0072] Each pair of teeth 74 is configured to receive a magnetic coil 80 such that the windings of this magnetic coil 80 extend around this pair of teeth 74, that is, around a radial axis connecting the center of the central wheel 71 with its periphery. To achieve this, the pairs of teeth 74 define gaps 77 between them. Each gap 77 is configured to receive two halves of magnetic coils 80 extending around the adjacent pairs of teeth 74 without these coils touching each other. Thus, in the example of [Fig. 7], 8 magnetic coils arranged in the circumferential direction are shown. According to some embodiments, the magnetic coils 80 can be immersed in a fluid. Each magnetic coil 80 can have a winding of wire, for example, enameled copper.

[0073] The peripheral wheels 72 are arranged on either side of the central wheel 71 so as to isolate the protruding ends of the magnetic coils 80 from the outer part of the stator 41. In other words, the thickness of the assembly of the peripheral wheels 72 and the central wheel 71 corresponds substantially to the longitudinal extension of the magnetic coils 80.

[0074] Each of the central wheel 71 and peripheral wheel 72 is advantageously formed by a stack of plates or sheets made of a magnetic or ferromagnetic material. This reduces eddy currents to optimize performance and reduce consumption, thus achieving better efficiency.

[0075] The stator toothed components 61, 62 are configured to be at least partially opposite the rotor toothed components 51, 52 during each movement of the rotor 33 along each coding direction Cl, C2. In particular, for example in a rest position, the central wheels 71 of the stator gears 61, 62 are arranged opposite the corresponding central wheels 57 of the rotor gears 51, 52. In a "push" or "pull" position of the rotor 33, the central wheels 71 of the stator gears 61, 62 are arranged opposite the corresponding peripheral wheels 57 of the rotor gears 51, 52. In each of these positions, the central wheels 71 of the stator gears 61, 62 are therefore arranged opposite the gears 57 of the rotor gears 51, 52. The same is true when the rotor 33 is rotated relative to the stator 4L

[0076] Thus, each central wheel 71 of the stator gear components 61, 62 is designed to cooperate magnetically with one of the gears 57 of the rotor gear components 51, 52 depending on the longitudinal position of the rotor 33. Furthermore, the circumferential tooth profiles of these wheels 71, 57 are synchronized. In other words, in such a case, each tooth of the rotor gear component(s) 51, 52 is in the same phase with its corresponding tooth of the stator gear component 61, 62.

[0077] The magnetic coils 80 are configured to be energized so as to create a torque and / or a notching force during the movement of the rotor 33 relative to the stator 41 and / or to detect and quantify each movement of the rotor 33 relative to the stator 41.

[0078] In particular, to create a detenting torque and / or force, the magnetic coils 80 can be supplied with a constant current so that two groups of coils 80 form opposite polarities, as illustrated in the left-hand part of [Fig. 8]. This detenting power supply can be switched off or reduced (standby mode) when the encoder 10 is not in use in order to avoid unnecessary energy consumption during rest phases. Furthermore, this device also allows the coil supply to be varied to modify the detenting according to the context of encoder use (for example, high torque during fine adjustment and very low torque, such as a potentiometer, during coarse adjustment) or to generate haptic feedback (for example: vibrating in the direction C1 and / or the direction C2 in the event of an operating error or an excessively long waiting time, or to confirm an input...).

[0079] The supply method illustrated on the left side of [Fig.8] creates a magnetic flux, referred to as long flux. Alternatively, it is possible to supply the magnetic coils 80 according to a short flux supply method on two adjacent magnetic coils 80, as shown in the right side of [Fig.8].

[0080] The number of teeth in each encoding direction is defined according to the corresponding longitudinal / circumferential toothed profiles. In particular, in the longitudinal direction, the number of teeth is defined by the longitudinal toothed profile of the rotor 33. In the example shown in the figures, this number is equal to 3, which ensures the "push" and "pull" functionalities of the encoder 10. In the circumferential direction, the number of teeth is defined by the corresponding circumferential toothed profiles. When these profiles are synchronized, the number of circumferential teeth is defined by the maximum number of teeth in these profiles (i.e., of the rotor or stator). Thus, in the example shown in the figures, the number of circumferential teeth is equal to 32, given that the circumferential toothed profile of each gear 57 of the components Rotor teeth 51, 52 define 32 teeth. When the circumferential toothed profiles are out of phase (i.e. when the teeth of one wheel are out of phase with the teeth of another wheel arranged opposite this first wheel), the number of teeth can be multiplied by a factor m corresponding to the number of different phases defined by these circumferential profiles.

[0081] An example of phase-shifted circumferential toothed profiles is illustrated in [Fig. 16]. In this example, a gear 85 mounted on the rotor 33 has 10 regularly spaced teeth and a gear 86 mounted on the stator 41 has 6 pairs of regularly spaced teeth and forms three different phases opposite the teeth of the rotor 10. In such a case, the number of circumferential teeth is equal to 30.

[0082] To quantify each movement of the rotor 33 relative to the stator 41, the magnetic coils 80 are configured to detect variations in inductance created by the mutual movement of the teeth of the different gears. Advantageously, the number of these variations detectable by the magnetic coils 80 corresponds to the number of teeth along each coding direction. Furthermore, the presence of several rotor and stator toothed components (two in the example shown in the figures) makes it possible to perform two detections in each coding direction and to determine the direction of movement along each coding direction. In particular, the detection of the direction of rotation is made possible by the phase shift of the gears 57 between the different rotor toothed components. In addition, a specific longitudinal profile can be used to detect the direction of movement along the longitudinal direction.

[0083] To ensure the detection of inductance variations, according to one embodiment, the magnetic coils 80 are supplied with test signals consisting of periodic currents of specific shape, phase, and frequency (at higher frequencies, in the 1 kHz - 1 MHz range). These signals are superimposed on the coil supply current, which is controlled at a low frequency, and on the DC current that produces the periodic torque / force peaks of the detent mechanism. The position of the rotor 33 can thus be determined by specific signal processing.

[0084] In some embodiments, the encoder 10 may further include additional detenting means that are independent of the magnetic coils 80 as explained above. These may, for example, be passive means consisting of one or more permanent magnets. Figure 9 illustrates various examples of such additional detenting means.

[0085] Thus, in example A of this [Fig. 9], at least one permanent magnet 90 is added between the rotor toothed components 51, 52 to increase the teething forces and torques in translation and rotation. The width of the permanent magnet 90 can be doubled to form a permanent magnet 92 as shown in example B of the same [Fig. 9].

[0086] Furthermore, in examples A and B of this [Fig. 9], an additional translational detenting device 91 is added. This device 91 significantly increases the translational force and provides a return force to the central position to avoid the use of a spring or to generate stable translational positions. This device 91 is preferably passive (no additional winding) and consists of one or more permanent magnets. The profiles of the teeth and / or magnets can be specific to ensure a force profile with improved tactile feedback. This added device is made with magnetic or ferromagnetic parts to ensure magnetic closure loops. The detenting device 91 can consist of a magnet 91 added opposite it in a toothed system (2 teeth on the rotor and 2 teeth on the stator are equivalent to the flanges 68 but made of magnetic or ferromagnetic material).This magnetic return system eliminates the need for a return spring in the central position.

[0087] In example C of [Fig.9], a permanent magnet 93 is added between the stator toothed components 61, 62. In addition, in this example, the detent device as explained previously may include a plurality of magnets 94 with alternating magnetic poles may be added to the stator 41 and the rotor 33 in their part between one of the rotor toothed components 51, 52 and the bearings 37 to form 1 to 3 stable positions and magnetic returns (as in the previous case) and avoid the use of a mechanical spring.

[0088] Figures 10 to 15 illustrate an incremental magnetic encoder 110 according to a second embodiment of the invention. This encoder 110 is substantially similar to the one described above and is particularly intended to be integrated at least partially into the panel 12, as illustrated in [Fig. 1].

[0089] Furthermore, as illustrated in [Fig. 10], the encoder 110 defines a rotor 133 and a stator 141 analogous to those described previously. Only characteristics differentiating from the first embodiment of these elements will be explained below.

[0090] In particular, with reference to Figures 11 to 13, the rotor 133 defines a plurality of rotor toothed components 151 to 154 (four in the example shown in the figures) arranged along the encoder axis X. Each rotor toothed component 151 to 154 comprises a pair of gears 157 spaced apart by a gap 158 of thickness dl. Each gear 157 is, for example, analogous to the gear 57 of the rotor toothed components 51, 52 described in relation to the first embodiment. In particular, each gear 157 can define the same number of teeth as the gear 57 described previously. The gears 157 of the same rotor toothed component 151 to 154 are synchronized (i.e., their teeth are aligned along the encoder axis X), and the gears 157 of toothed components The adjacent rotors 151 to 154 are phase-shifted by a predetermined phase angle. This phase angle can be substantially equal to the phase angle θ described in relation to the first embodiment.

[0091] As can be seen in [Fig. 11], the stator 141 comprises a stator toothed component 161 to 164 for each rotor toothed component 151 to 154 and means 165 for securing these stator toothed components 161 to 164. The securing means 165 are, for example, substantially similar to those described previously and include, in particular, flanges, screws, etc. The stator toothed components 161 to 164 can thus be aligned along the encoder axis X.

[0092] The stator toothed components 161 to 164 are arranged side by side along the encoder axis X to receive the respective rotor toothed components 151 to 154 when the encoder 110 is in its rest position. These stator toothed components 161 to 164 are, for example, substantially similar to each other, and only the stator toothed component 161 will be described in detail with reference to [Fig. 14].

[0093] Thus, as illustrated in [Fig.14], the stator toothed component 161 comprises a magnetic coil 180 and a pair of peripheral gears 172 arranged axially with the magnetic coil 180, trapping this magnetic coil 180 between them.

[0094] Each peripheral gear 172 is intended to be arranged opposite one of the gears 157 of the rotor gear components 151 to 154. In addition, in the example of the figures, each peripheral gear 172 is in phase with each gear 157 of the rotor gear components 151 to 154 and defines, for example, the same number of teeth.

[0095] The magnetic coil 180 defines a winding around the encoder shaft X extending between the peripheral gears 172. This coil 180 is intended to be positioned opposite one of the spaces 158 of the rotor gear components 151 to 154. Its thickness is therefore substantially equal to dl.

[0096] As in the previous embodiment, the magnetic coils 180 are configured to be powered so as to create a torque and / or a notching force during the movement of the rotor 133 relative to the stator 141 and / or to detect and quantify each movement of the rotor 133 relative to the stator 141, and this according to each coding direction.

[0097] In particular, according to this embodiment, only one detection is performed by each coding direction. This detection can be implemented in a manner analogous to that explained previously. Furthermore, the direction of rotation can be determined by means of the phase angle θ between the gears 157 of the different rotor toothed components 151 to 154. The direction of movement along the axis of X encoder can be determined by using a specific toothed longitudinal profile along this X axis and / or the detections made by the different magnetic coils 180 taking into account their respective positions along the X encoder axis.

[0098] Regarding the detent torques, a specific power supply for the magnetic coils 180 allows for the creation of 32 detents in the circumferential direction and up to 4 detents in the longitudinal direction. This power supply for the detent can be deactivated or reduced (standby mode) when the encoder 110 is not in use in order to avoid unnecessary energy consumption during rest phases. Furthermore, this device also allows the coil power supply to be varied to modify the detents according to the context of encoder use (for example, high torque during fine adjustment and very low torque, such as a potentiometer, during coarse adjustment) or to generate haptic feedback (for example: vibrating in the Cl and / or C2 directions in the event of an operating error or an excessively long waiting time, or to confirm an input...).

[0099] Finally, as in the previous case, in certain embodiments, the encoder 110 may further include additional detenting means that are independent of the magnetic coils 180 as explained previously. These may, for example, be passive means consisting of one or more permanent magnets. Figure 15 illustrates various examples of such additional detenting means.

[0100] Thus, in Example A of this [Fig. 15], a permanent magnet 190 is added in each space 158 formed between a pair of gears 157 of the rotor toothed components 151 to 154, to increase the teething forces and torques in translation and rotation. Furthermore, a magnet 191 can be added opposite it in a toothed system (2 teeth on the rotor and 2 teeth on the stator are equivalent to the flanges 68 but made of magnetic or ferromagnetic material). This is to create axial teething and return forces to the stable push / pull position. This avoids the use of a mechanical spring.

[0101] Furthermore, in Examples B and C of this [Fig. 15], an additional translational detenting device 192 is added. This device 192 significantly increases the translational force and provides a return force to the central position to avoid the use of a spring or to generate stable translational positions. This device 192 is preferably passive (no additional winding) and consists of a plurality of permanent magnets. The profiles of the teeth and / or magnets can be specific to ensure a force profile with improved tactile feedback. This added device is made with magnetic or ferromagnetic parts defining alternating magnetic poles to ensure magnetic closure loops. These magnetic parts are added on the stator 141 and the rotor 133 in their part between the rotor toothed component 151 and the bearings 37. This device with magnetic return avoids the use of a return spring in the central position.

[0102] In example C of [Fig. 15], a permanent magnet 193 is added between the carcasses of each magnetic coil 180.

Claims

Demands

1. Incremental magnetic encoder (10; 110) defining an encoder axis (X) and comprising a fixed body and a movable body relative to the fixed body along at least one first encoding direction (Cl); one of the bodies, called the first body (21), comprising: - a first toothed component (51; 151) extending along a longitudinal direction coinciding with the encoder axis (X) and a circumferential direction perpendicular to the longitudinal direction, one of said directions corresponding to the first encoding direction (Cl), the first toothed component (51; 151) defining a plurality of teeth made of magnetic or ferromagnetic material and arranged along the first encoding direction (Cl); the other body, called second body (22; 122), comprising: - a second toothed component (61; 161) extending along the longitudinal and circumferential directions, the second toothed component (61;161) defining a tooth made of magnetic or ferromagnetic material and arranged opposite the teeth of the first toothed component (51; 151) during each movement of the moving body along the first coding direction (Cl); - at least one pair of magnetic coils (80; 180) configured to measure each variation of inductance between the first toothed component (51; 151) and the second toothed component (61; 161), to quantify each movement of the moving body along the first coding direction (Cl).;

2. Encoder (10; 110) according to claim 1, wherein the teeth of the first toothed component (51; 151) are arranged along the first coding direction (Cl) with a constant pitch.

3. Encoder (10; 110) according to claim 1 or 2, wherein: - the first coding direction (Cl) corresponds to the circumferential direction; - the second toothed component (61; 161) comprises a plurality of teeth arranged in the circumferential direction opposite the teeth of the first toothed component (51; 151) in a synchronous or out-of-phase manner.

4. Encoder (10; 110) according to any one of the preceding claims, wherein the moving body is movable relative to the fixed body further along a second coding direction (C2) perpendicular to the first coding direction (C1); the first toothed component (51; 151) further defining a plurality of teeth made of magnetic or ferromagnetic material and arranged along the second coding direction (C2); the second toothed component (61; 161) defining a tooth made of magnetic or ferromagnetic material and arranged opposite the teeth of the first toothed component (51; 151) during each displacement of the moving body along the second coding direction (C1); at least one pair of magnetic coils (80; 180) being configured to measure each change in inductance between the first toothed component (51; 151) and the second toothed component (61;161), to quantify each movement of the moving body according to the second coding direction (C2).;

5. Encoder (10; 110) according to any one of the preceding claims, wherein the first toothed component (51; 151) comprises a plurality of toothed wheels (57; 157) arranged along the encoder axis (X).

6. Encoder (10; 110) according to claim 5, wherein the gear wheels (57; 157) are spaced apart to form a plurality of teeth along the encoder axis (X).

7. Encoder (10; 110) according to claim 5 or 6, wherein the second toothed component (61; 161) comprises at least one toothed wheel (71; 172) arranged coaxially with at least one toothed wheel (57; 157) of the first toothed component (51; 151) at least in a rest position of the encoder (10; 110).

8. Encoder (10) according to claim 7, comprising a plurality of magnetic coils (80) arranged circumferentially on the toothed wheel (71) of the second toothed component (61); preferably, each magnetic coil (80) extending around a pair of teeth formed by the toothed wheel (71) of the second toothed component (61).

9. Encoder (110) according to claim 7, wherein: - the second toothed component (161) comprises at least two toothed wheels (172) arranged along the encoder axis (X); - at least one magnetic coil (180) is disposed between said toothed wheels (172) of the second toothed component (161) and extends around the encoder axis (X).

10. Encoder (10; 110) according to any one of the preceding claims, comprising at least two first toothed components (51; 151) arranged along the encoder axis (X) and at least two second toothed components (61; 161) arranged coaxially with the first toothed components (51; 151).

11. Encoder (10; 110) according to claim 10, wherein: - each first toothed component (51; 151) comprises at least one toothed wheel (57; 157); - the toothed wheels (51; 151) corresponding to different first toothed components (51; 151) are phase-shifted by a predetermined angle.

12. Encoder (10; 110) according to any one of the preceding claims, wherein the magnetic coils (80; 180) are configured to be energized during operation of the encoder (10; 110), to create a torque or detenting force between the first toothed component (51; 151) and the second toothed component (61; 161) during each respective movement of these components along the first encoding direction (Cl) and / or a second encoding direction (C2).

13. Encoder (10; 110) according to claim 12, wherein the magnetic coils (80; 180) are configured to be powered according to a context of use of the encoder (10; 110) or to generate haptic feedback.

14. Encoder (10; 110) according to claim 12 or 13, wherein the number of notches along a coding direction (Cl, C2) is determined by the number of teeth of the first toothed component (51; 151) or of the second toothed component (61; 161) along this coding direction (Cl, C2).

15. Encoder (10; 110) according to any one of claims 12 to 14, further comprising one or more permanent magnets arranged to enhance the torque and / or the detenting force and / or generate a torque and / or a return force.

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