Method for determining the relative angular position between two components and sensor system and method for manufacturing a magnetic element

Abstract

The invention relates to a method for determining the relative angular position between two components about an axis of rotation (A) using a magnetized body (10) in the form of an angular sector curved about the axis of rotation (A), characterized in that a magnetization plane (PM) of the magnetized body is parallel to the axis of rotation (A). The invention relates to a sensor system comprising such a magnetized body and to a method for producing such a magnetized body.

Description

Technical Field

[0001] The invention relates to a method for determining the relative angular position of a first component relative to a second component about a rotation axis, said method advantageously being implemented using a magnetic position sensor. The invention also relates to a method for manufacturing a magnetic body for the aforementioned method and for the aforementioned sensor system. Background Art

[0002] The technical advantages of magnetic sensor systems are well known. They can be produced at relatively low cost, they do not experience significant mechanical wear, and they are almost insensitive to moisture and non-magnetic dirt (dust, oil, etc.). Due to these advantages, magnetic sensor systems are often used in automotive applications.

[0003] The magnetic angular position sensor system comprises at least one magnetized body having a permanent magnetization and at least one magnetic field measurement cell, the sensor system being arranged to measure a relative position of the measurement cell with respect to the magnetized body about a rotation axis.

[0004] In practical applications, the mechanism to be monitored comprises a first part and a second part that are rotationally movable relative to each other. The magnetized body is made fastened to the first part, or integrated in the first part, while the one or more measuring units are made fastened to the second part of the mechanism, and the sensor system allows the relative position of the two parts of the mechanism to be determined.

[0005] In some cases, it is desirable to be able to measure relative position over angular travel.

[0006] Typically, in applications in the automotive field, the sensor system is used to determine the angular position of a control lever of an automatic gearbox. According to another application, the sensor system can be used to determine the angular position of an output member of an actuator, for example for a parking brake actuator. The present invention aims to solve problems associated with the practical implementation of sensor systems, which are typically intended to be integrated in confined spaces with limited available volume and in which ferromagnetic components are typically present in the vicinity of the sensor system, which may reduce the accuracy of the determination of the angular position.

[0007] Document EP-2.212.652 discloses a method in which a sensor system is implemented by using a combination of radial and tangential components of a magnetic field generated by a magnetized body. In this method, a first component is provided with a magnetized body in the form of a cylindrical ring of revolution around an axis of rotation and having at any point of the magnetized body a magnetization whose magnetization vector is:

[0008] parallel to the fixed magnetization plane of the magnetized body, and

[0009] There is a continuously variable direction in the magnetization plane that varies with the position of a point of the magnetized body in the magnetization plane along a direction perpendicular to the axis of rotation.

[0010] The second component is equipped with:

[0011] a first measuring unit at a first measuring point, delivering two electrical signals representing respectively a primary component and a secondary component of a magnetic field generated by a magnetized body in the measuring plane at the measuring point of the unit under consideration,

[0012] The second measuring unit at the second measuring point delivers two electrical signals representing respectively the primary component and the secondary component of the magnetic field generated by the magnetized body in the measuring plane at the measuring point of the unit under consideration.

[0013] The method determines a value representative of the relative angular position between two components by determining an angle whose tangent is a function of the differential composition of the components measured by the two units for a given relative angular position.

[0014] However, achieving the magnetization necessary for operation of the method on a magnet that is bent about the main axis is complex to implement in an industrial environment.

[0015] Document WO2007099238 describes a sensor using a magnetization that varies along the stroke. However, in the case of a rotary sensor with a rigid permanent magnet, such a magnetization requires a magnetizing head with a complex and often difficult to realize geometry.

[0016] Other solutions with a changing magnetization direction for producing linear sensors are proposed in documents DE102012111653, US6545463, EP0997706. The teachings of these documents cannot be directly transferred to angular position sensors, because it is difficult to achieve the proposed magnetization strength and the magnetic field in the sensor may be too weak, especially for cheap permanent magnets (such as ferrites).

[0017] US8022694 proposes a magnetization and a magnetizing head for producing it. However, this solution does not allow to optimize the magnetization angle obtained in the volume of the magnet, and in addition, within the thickness required for this application, the magnetization of a sufficiently powerful magnet would require very large currents and therefore expensive electronics that cannot even be manufactured.

[0018] Document EP 2 488 830 of the applicant proposes a magnetized body for an angular position sensor, the magnetization angle of which varies depending on the rotational position, but the magnetization plane is perpendicular to the rotational axis. Summary of the invention

[0019] The present invention aims to define a method for determining the relative angular position between two components which allows the use of a sensor system which is easier to manufacture on an industrial scale.

[0020] For this purpose, the invention proposes a method for determining the relative angular position of a first component relative to a second component over an angular travel about an axis of rotation, wherein:

[0021] The first component is provided with a magnetized body in the shape of an angular curved sector around the axis of rotation, the angular sector comprising several consecutive angular portions or a single angular portion around the axis of rotation, the magnetized body having at any point of at least one angular portion of the magnetized body a magnetization whose magnetization vector:

[0022] a fixed magnetization plane parallel to said angular portion of the magnetized body, and

[0023] having a continuously variable direction in the magnetization plane that varies with the position of a point of the magnetized body in the magnetization plane along a direction perpendicular to the axis of rotation;

[0024] the second part being equipped with at least a first measuring unit at a first measuring point, delivering two electrical signals representing respectively a primary component and a secondary component of a magnetic field generated by a magnetized body in the measuring plane at the measuring point of the unit under consideration,

[0025] For a given relative angular position, the method determines a value representative of the relative angular position between the two components as a function of the component measured by the measuring unit.

[0026] The method is characterized in that the magnetization plane of the magnetized body is parallel to the axis of rotation.

[0027] Based on other features of the method according to the invention, individually or in combination:

[0028] The magnetized body may comprise a single angular portion, the magnetized body then having at any point of the magnetized body a magnetization whose magnetization vector:

[0029] a single fixed magnetization plane parallel to the magnetized body, and

[0030] It has a continuously variable direction in the magnetization plane that varies with the position of a point of the magnetized body in the magnetization plane along a direction perpendicular to the axis of rotation (A).

[0031] The magnetization plane may be perpendicular to a radius originating from the axis of rotation. The magnetization plane may in particular be perpendicular to a radius originating from the axis of rotation and included in the angular extent of the magnetized body around the axis of rotation. The magnetization plane may more particularly be perpendicular to a radius originating from the axis of rotation and oriented along a bisector of the angular extent or extent of the magnetized body.

[0032] The magnetized body may comprise at least a first angular portion and at least a second angular portion different from each other around the axis of rotation, the magnetized body then having a magnetization whose magnetization vector:

[0033] At any point of the first angular portion of the magnetized body, parallel to the first fixed magnetization plane,

[0034] at any point of the second angular portion of the magnetized body, parallel to the second fixed magnetization plane, and

[0035] In the considered magnetization plane there is a continuously variable direction that varies with the position of the point of the considered angular portion of the magnetized body in the considered magnetization plane along a direction perpendicular to the axis of rotation.

[0036] For each angular portion, the magnetization plane may be perpendicular to a radius originating from the axis of rotation and included in the angular range of the angular portion under consideration.

[0037] The second component can be equipped with a second measurement unit at a second measurement point, delivering two electrical signals representing respectively the main component and the secondary component of the magnetic field generated by the magnetized body in the measurement plane at the measurement point of the unit under consideration, and for a given relative angular position, the method makes it possible to determine the value representative of the relative angular position between the two components by determining a raw angle, the tangent of which is a function of the difference of the components measured by the two units.

[0038] The first measurement unit and the second measurement unit may be arranged on the second component such that primary measurement axes of the first measurement unit and the second measurement unit are parallel to each other, and such that secondary measurement axes of the first measurement unit and the second measurement unit are parallel to each other;

[0039] For a given relative angular position, the method can determine a value representative of the relative angular position between the two components by determining an original angle whose tangent is a function of the ratio between the difference of the secondary component on the one hand and the primary component on the other hand measured by the two units.

[0040] The first measurement point of the first measurement unit and the second measurement point of the second unit may be arranged at an equal distance from the rotation axis and may be arranged in positions spaced at a non-zero fixed angle around the rotation axis.

[0041] The first measurement point of the first measurement unit and the second measurement point of the second unit may be arranged in positions spaced apart at a non-zero fixed angle around the rotation axis and strictly less than 90 degrees (preferably less than 30 degrees, more preferably less than or equal to 20 degrees around the rotation axis).

[0042] The first measuring unit and the second measuring unit can be arranged on the second component so that a primary measuring axis of the first measuring unit and the second measuring unit or a secondary measuring axis of the first measuring unit and the second measuring unit is oriented along the direction of a bisector of an angular deviation between two measuring points measured around the rotation axis in a plane perpendicular to the rotation axis.

[0043] The first measuring point of the first measuring unit and, where appropriate, the second measuring point of the second unit can be arranged at a distance from the rotation axis that is smaller than the radius of the outer cylindrical surface of the magnetized body while being offset from the magnetized body in the direction of the rotation axis.

[0044] The magnetized body may have the shape of a segment of a tubular sector, which is a cylinder rotated about a main axis.

[0045] The magnetized body may have the shape of a segment of an angular sector of a disk, said shape being a cylinder of revolution about a main axis of rotation.

[0046] The magnetized body may have the shape of an angular sector of 180 degrees or less around the axis of rotation.

[0047] The measuring plane of the measuring unit may be parallel to the axis of rotation.

[0048] The invention also relates to a sensor system for determining the relative angular position of a first component with respect to a second component over an angular travel about an axis of rotation, the system comprising:

[0049] A magnetized body in the shape of a curved angular sector around a main axis parallel to the axis of rotation, said angular sector comprising several consecutive angular portions or a single angular portion around the main axis, and having at any point of at least one angular portion of the magnetized body a magnetization whose magnetization vector:

[0050] a fixed magnetization plane parallel to said angular portion of the magnetized body, and

[0051] having a continuously variable direction in the magnetization plane that varies with the position of a point of the magnetized body in the magnetization plane along a direction perpendicular to the axis of rotation;

[0052] a first measuring unit at a first measuring point, delivering two electrical signals representing respectively a primary component and a secondary component of a magnetic field generated by a magnetized body in the measuring plane at the measuring point of the unit under consideration,

[0053] The second measuring unit at the second measuring point delivers two electrical signals representing respectively the primary component and the secondary component of the magnetic field generated by the magnetized body in the measuring plane at the measuring point of the unit under consideration.

[0054] The sensor system is characterized in that the magnetization plane of the magnetized body is parallel to the axis of rotation.

[0055] Based on other features of the system according to the invention, individually or in combination:

[0056] The magnetized body may comprise a single angular portion, the magnetized body having at any point of the magnetized body a magnetization whose magnetization vector:

[0057] a single fixed magnetization plane parallel to the magnetized body, and

[0058] There is a continuously variable direction in the magnetization plane that varies with the position of a point of the magnetized body in the magnetization plane along a direction perpendicular to the main axis.

[0059] The magnetization plane may be perpendicular to a radius originating from the main axis. The magnetization plane may in particular be perpendicular to a radius originating from the axis of rotation and included in the angular range of the magnetized body around the axis of rotation. The magnetization plane may more particularly be perpendicular to a radius originating from the axis of rotation and oriented along a bisector of the angular range or angular range of the magnetized body.

[0060] The magnetized body may comprise at least a first angular portion and at least a second angular portion different from each other around the main axis, the magnetized body then having a magnetization whose magnetization vector:

[0061] At any point of the first angular portion of the magnetized body, parallel to the first fixed magnetization plane,

[0062] at any point of the second angular portion of the magnetized body, parallel to the second fixed magnetization plane, and

[0063] It has a continuously variable direction in the considered magnetization plane that varies with the position of a point of the considered angular portion of the magnetized body in the considered magnetization plane along a direction perpendicular to the main axis (A′).

[0064] For each angular portion, the magnetization plane may in particular be perpendicular to the radius originating from the main axis and comprised in the angular range of the angular portion under consideration.

[0065] The system may comprise a second measuring unit at a second measuring point, delivering two electrical signals representing respectively a primary component and a secondary component of a magnetic field generated by a magnetized body in the measuring plane at the measuring point of the unit under consideration, and the sensor system may determine, for a given relative angular position, a value representative of the relative angular position between the two parts by determining an original angle whose tangent is a function of the difference of said components measured by the two units.

[0066] The first measuring unit and the second measuring unit may be arranged such that primary measuring axes of the first measuring unit and the second measuring unit are parallel to each other and such that secondary measuring axes of the first measuring unit and the second measuring unit are parallel to each other.

[0067] The system may comprise a calculation unit programmed to determine, for a given relative angular position, a value representative of the relative angular position between the two components by determining an original angle whose tangent is a function of the ratio between the difference of the secondary component on the one hand and the difference of the primary component on the other hand measured by the two units.

[0068] The first measurement point of the first measurement unit and the second measurement point of the second unit may be arranged at an equal distance from the rotation axis and in positions spaced apart by a non-zero fixed angle.

[0069] The first measurement point of the first measurement unit and the second measurement point of the second unit may be arranged in positions spaced apart at a non-zero fixed angle and strictly less than 90 degrees around the rotation axis (preferably less than 30 degrees, more preferably less than or equal to 20 degrees around the rotation axis).

[0070] The first measuring point of the first measuring unit and, where appropriate, the second measuring point of the second unit can be arranged at a distance from the rotation axis that is smaller than the radius of the outer cylindrical envelope surface of the magnetized body while being offset from the magnetized body in the direction of the rotation axis (A).

[0071] The first measuring unit and the second measuring unit may be arranged such that a primary measuring axis of the first measuring unit and the second measuring unit or a secondary measuring axis of the first measuring unit and the second measuring unit is oriented along the direction of a bisector of an angular deviation between two measuring points, the angular deviation being measured around the rotation axis in a plane perpendicular to the rotation axis.

[0072] The magnetized body may have the shape of a segment of a tubular sector, which is a cylinder rotated about an axis of rotation, or the magnetized body may have the shape of a segment of an angular sector of a disk, which is a cylinder rotated about an axis of rotation.

[0073] The magnetized body may have the shape of an angular sector having an angular extent greater than 60 degrees, preferably greater than 80 degrees, or even equal to 360 degrees around the axis of rotation.

[0074] The magnetized body may have the shape of an angular sector of a cylinder rotated about a main axis.

[0075] The main axis may coincide with the axis of rotation.

[0076] The measuring plane of the measuring unit may be parallel to the axis of rotation.

[0077] The invention also relates to a method for manufacturing a magnetizable body for use in a system for determining the relative angular position of a first component relative to a second component about an axis of rotation, the method comprising: providing a body of magnetizable material having the shape of a curved angular sector and having an angular extent about a main axis, wherein the angular sector comprises several consecutive angular portions or a single angular portion about the main axis.

[0078] The method is characterized in that it comprises, for at least a first angular portion of the magnetized body:

[0079] a first network of parallel electric conductors is arranged in the vicinity of a first angular portion of the body of magnetizable material, said first network comprising bundles of several parallel electric conductors having an orientation perpendicular to the main axis and parallel to a first directrix radius originating from the main axis and included in the angular extent of the considered first angular portion of the magnetizable body, said bundles being laterally offset from each other along an offset direction perpendicular to their orientation and perpendicular to the main axis;

[0080] The flow of electric current in the bundles of electric conductors, the direction of the current flow being defined in a fixed reference system relative to the magnetized body, being the same in all the conductors of the same bundle and being opposite in two adjacent bundles, thereby forming one or several output bundles and one or several input bundles, in which the current flows in a first direction and in which the current flows in a second direction opposite to the first direction, the current flowing in the bundles being able to generate a magnetizing magnetic field around the network and in the magnetizable material body suitable for magnetizing the magnetizable material body.

[0081] Based on other features of the method according to the invention, individually or in combination:

[0082] The first network of parallel electrical conductors may extend facing a first portion of the body of magnetisable material, said first portion being a single portion covering an angular extent of the body of magnetisable material.

[0083] The first directrix radius may be oriented along a line that bisects the angular extent of the body of magnetizable material.

[0084] A first network of parallel electric conductors may extend facing a first portion of the body of magnetizable material, and a second network of parallel electric conductors may extend facing a second portion of the body of magnetizable material different from the first portion, the bundle of parallel electric conductors of the second network being oriented along a second orientation perpendicular to the main axis and parallel to a second directrix radius originating from the main axis and included in the angular range of the second angular portion under consideration.

[0085] The electrical conductor of the bundle may be formed by a segment of at least one winding of wire, along which at least a conductor of the output bundle, a connecting segment, a conductor of the input bundle, a further connecting segment and a further conductor of the output bundle repeatedly follow one another. BRIEF DESCRIPTION OF THE DRAWINGS

[0086] Various other characteristics emerge from the following description given with reference to the accompanying drawings which show, by way of non-limiting example, embodiments of the object of the invention:

[0087] Figure 1A is a schematic perspective view showing one embodiment of a sensor system for implementing the present invention and comprising a single measuring unit;

[0088] Figure 1B is with Figure 1A A similar view shows an embodiment of a sensor system for implementing the invention and comprising two measuring units;

[0089] Figure 2A yes Figure 1B a schematic top view of the system in a plane perpendicular to the axis of rotation in the direction of the axis of rotation in a position referred to as a reference position of the magnetized body relative to the measuring unit;

[0090] Figure 2B is with Figure 2A Similar views for any position of the magnetized body relative to the measuring unit;

[0091] Figure 3 yes Figure 1B A schematic front view of the system along a radial direction perpendicular to the rotation axis;

[0092] Figure 4 yes Figure 1B A schematic cross-sectional view of the system along a plane containing the axis of rotation;

[0093] Figure 5 yes Figure 1B The system is along the radial direction perpendicular to the rotation axis and Figure 3 a similar schematic elevational view showing more particularly the magnetization of the magnetized body;

[0094] Figure 5A yes Figure 5 an enlarged view of a portion of;

[0095] Figure 6 is along the direction of the rotation axis Figure 2A A similar schematic top view showing a magnetization method for producing a magnetized body for implementing a sensor system according to the invention;

[0096] Figure 7 is a schematic front view along a radial direction perpendicular to the rotation axis, showing a magnetization method for manufacturing a magnetized body for implementing the sensor system of the present invention;

[0097] Figure 8 The steps of the method according to the present invention are shown;

[0098] Fig. 9 A variation of the magnetized body is shown;

[0099] Fig.10 and Fig.11 is with Figure 7 A similar view showing a variant of a magnetizing head for manufacturing a magnetizing body for implementing a sensor system according to the invention;

[0100] Fig. 12A and Fig. 12B shows the results obtained by simulation for a configuration with a single measuring unit, respectively showing the components By and BZ of the magnetic field on the one hand and the original angle or magnetic angle on the other hand which can be derived from these components as a function of the angular position of the two components;

[0101] Fig.13A and Fig. 13B shows, for a configuration with two measuring units, results obtained by simulation, respectively showing the values ​​of the magnetic field at each of the two measuring points representing the difference of the first component on the one hand and of the second component on the other hand, and the original angle or magnetic angle on the other hand which can be derived from these components as a function of the angular position of the two components; and

[0102] Fig.14A variant of the invention is shown to obtain a magnetized body comprising a first angular portion and a second angular portion different from each other, each of which has its own magnetization plane. DETAILED DESCRIPTION

[0103] The drawing shows an exemplary embodiment of a magnetic position sensor system 1 which allows the method according to the invention for determining a relative angular position to be implemented.

[0104] In these first embodiments, the sensor system 1 is designed to determine the relative position of two components 14, 16 which may be moved relative to each other along a rotational movement axis A on the one hand. In the example, there are no other relative displacement axes. It is assumed that there is no relative movement of the two components 14, 16 in a radial direction relative to the rotational axis A. Thus, the sensor system 1 can be used, for example, to detect the position of an automatic gearbox control lever, the sensor system being arranged, for example, at the hinge axis of the lever.

[0105] The sensor system 1 comprises, on the one hand, a A magnetized body 10, and at least one magnetic field measuring unit 11, 12. In some embodiments, two measuring units 11, 12 will be provided. In practical applications, the magnetized body 10 is intended to be fixed to a first part 14 of a mechanism (e.g. a rotary hinge axis of a lever, a steering column or an output shaft of an actuator), the first part of the mechanism being movable relative to a second part 16 of the mechanism (e.g. a fixed part of the vehicle structure or a supporting part of the sensor system 1).

[0106] The sensor 1 is provided to determine the relative angular position of the magnetized body 10 relative to a measuring unit or relative to a plurality of measuring units 11, 12 about the rotation axis A. Thus, it is possible to determine the relative angular position of the magnetized body 10 relative to a measuring unit or relative to a plurality of measuring units 11, 12 about the rotation axis A. The relative movement between the magnetized body 10 and the measuring units 11, 12 is described in the example considered, which is a simple rotation, the basis vector and is contained in a plane perpendicular to the rotation axis A, the origin 0 is a point on the rotation axis A, and the basis vectors and The directions of are arbitrary but orthogonal to each other. Therefore, the basis vectors parallel to the axis of rotation A. In this reference system, for example, we can consider the basis vector and The direction of is associated with the second part 16 carrying the measuring units 11, 12. In the example shown, the radial basis vector is oriented so that it originates from the rotation axis A and is along the radial basis vector The oriented radius passes through the measuring point of the unit, in a two-unit system arbitrarily through the measuring point of the first measuring unit 11. In this reference system, the first component 14 is movable and the second component 16 is fixed, but this is arbitrary as long as only a relative movement between the two components 14, 16 is taken into account.

[0107] The magnetized body 10 has a geometry in the shape of a curved angular sector about a main axis A′ which in the sensor system is preferably parallel to the axis of rotation A. Preferably, the main axis A′ coincides with the axis of rotation A.

[0108] In the example shown, the magnetized body 10 has a geometry in the shape of an angular sector, which is a cylinder around the main axis A', that is to say a volume formed by a straight generatrix parallel to the main axis A', following a closed curve, in an angular sector around the main axis A'. More specifically, in the case of the example shown, it can be provided that the magnetized body 10 has a geometry in the shape of an angular sector, which is a cylinder rotated around the main axis A'. In some examples, the magnetized body 10 more specifically has the shape of a segment of a tubular sector, which is a cylinder rotated around the main axis A'. The magnetized body can also have the shape of a segment of an angular sector of a disk, which is a cylinder rotated around the main axis of rotation A', thus in the form of a "portion of a pie chart".

[0109] In the example shown, the magnetized body 10 has an angular range of less than 360 degrees around the main axis A'. Then, an "annular sector" geometry is presented, which has the shape of a segment of a tubular sector, which is a cylinder rotated around the main axis A', which is angularly bounded around the main axis A' by two side faces 9 parallel to the main axis A'. The angular range of the magnetized body 10 is preferably greater than the relative angular stroke, along which it is expected that the positions of the two components 14, 16 can be determined. However, in some cases, it is possible to have a magnetized body with an angular range less than or equal to the relative angular stroke. In some of the examples shown, the magnetized body 10 is in the shape of a tubular segment, which is a cylinder rotated around the main axis A', having an angular range included in the angular range of 70 to 100 degrees. However, the angular sector can have an angular range including an angular range of 20 to 120 degrees around the main axis A', or even an angular range greater than 120 degrees, until close to or equal to 180 degrees.

[0110] Fig. 9 1 to 3 show another possible example of the geometry of the magnetized body 10. In this case, in top view, the magnetized body has a central portion 13 with the same geometry as in FIGS. Figure 4The magnetized body 10 has the same geometry as the magnetized body 10, that is, the geometry of a cylinder rotated around the main axis A'. However, in this variant, the central part 13 is extended at each end of its angular range by straight end segments 15, which extend it on either side by extending tangentially around the main axis A' on the extension of the central part 13 starting from the angular end of the central part 13. In the example, these straight end segments have the same section as the central part. In this example, the edges of the straight end segments 15 are chamfered to have a quarter-circle chamfer. Overall, the magnetized body 10 also has the shape of a curved angular sector around its main axis A'.

[0111] In the example shown, the magnetized body 10 is made in one piece extending over the entire angular extent. However, it can be made of several magnetized body elements which are arranged side by side along the angular extent.

[0112] exist Figure 1A or Figure 1B In the example of the magnetized body 10 is arranged on the shaft 14, at a distance from the longitudinal ends of the shaft, so that a segment of the shaft 14 is located on each side of the magnetized body 10. However, a configuration can be provided in which the magnetized body is arranged at the shaft end, at its longitudinal ends. In this case, the magnetized body can have the geometry of a disk or an angular disk sector.

[0113] Of course, the magnetized body 10 has a thickness in a radial direction relative to the rotation axis A. In some applications, this thickness may be comprised within a range of 2 to 20 mm, even within a range of 3 to 15 mm, even within a range of 5 to 12 mm.

[0114] The magnetized body 10 has a front envelope surface 3. Figure 1A to Figure 1B In the example shown, the front envelope surface is an outer cylindrical surface of rotation of the magnetized body. In general, in particular for applications for measuring the angular position of a gear lever, the magnetized body may have an outer radius corresponding to the radius of the front envelope surface 3, which may be comprised in the range of 10 mm to 45 mm. For other applications, larger or smaller diameters may be realized.

[0115] The magnetized body 10 is delimited in the axial direction by two end faces 5, 7. Preferably, at least one of these end faces (here for example the flat surface which will be arbitrarily considered to be the upper surface 5) is a flat surface extending along a plane perpendicular to the main axis A' and therefore, in the sensor system 1, perpendicular to the axis of rotation A. In the example shown, the two opposite upper end faces 5 and the lower end face 7 of the magnetized body 10 are flat surfaces, each of which is contained in a plane perpendicular to the main axis A'.

[0116] The axial dimension of the magnetized body 10 between its two end faces 5 , 7 is, for example, comprised in the range of 2 to 12 mm.

[0117] In the method, preferably, the magnetized body 10 is arranged so that its main axis A' coincides with the axis of rotation A of the relative movement between the first part 14 and the second part 16. However, radial offsets between these two axes are possible, either spontaneously or due to mounting errors, for example due to geometrical tolerances of the components of the mechanism or its components.

[0118] During the relative displacement between the measuring units 11, 12 on the one hand and the magnetized body 10 on the other hand, the measuring units 11, 12 move relatively facing one of the end faces 5, 7 of the magnetized body 10. In this example, it is the upper end face 5. In this example, during the relative displacement between the magnetized body 10 and the measuring units 11, 12, the air gap distance "e" between the measuring units 11, 12 and the end face 5 of the magnetized body 10 remains constant along the axial direction of the rotation axis A. However, it is not excluded that the air gap distance may vary over at least a part of the operating area range.

[0119] The relative angular position determination using the sensor system 1 is performed for any relative angular position between the measuring units 11 , 12 and the magnetized body 10 which varies between two different extreme relative angular positions about the rotation axis A, whose angular deviation about the rotation axis A determines the relative angular travel.

[0120] Figures 1A to 13B The example of considers a magnetizing body 10 having the shape of an angular sector comprising a single angular portion, covering the entire angular extent of the magnetizing body 10 around the main axis A′ and having the same magnetization plane over this entire angular extent of the magnetizing body 10 .

[0121] In this case, if Figure 5 As more particularly shown in FIG. 1 , at any magnetization point of the magnetized body 10, the magnetization vector of the material constituting the magnetized body 10 is

[0122] parallel to a fixed magnetization plane PM of the magnetized body, which is parallel to the main axis A′ of the magnetized body and, therefore, in the sensor system 1 , to the axis of rotation A, and

[0123] In the magnetization plane PM it has a continuously variable direction that varies with the position of the considered point P of the magnetized body in the direction Y perpendicular to the main axis in the magnetization plane PM.

[0124] The magnetization plane PM is a fixed plane relative to the magnetization body. Figures 1A to 13BIn the example shown, the magnetization plane PM is perpendicular to the bisector of the angular range of the magnet. More generally, the magnetization plane PM can be perpendicular to the radius of the main axis A' originating from the angular sector of the magnetized body 10, which radius is included in the angular range of the magnetized body around the main axis A'. This radius originating from the main axis A' can be included in a limited range around the orientation of the bisector of the angular range of the magnet, and the magnetization plane PM can be perpendicular to the main axis. This limited range is, for example, a range of 15 degrees centered on the orientation of the bisector of the angular range of the magnet.

[0125] In the application of the sensor system, it can be provided that the magnetization plane is preferably perpendicular to a radius originating from the rotation axis A and oriented along the bisector of the angular extent of the magnetized body. More generally, the magnetization plane PM can be perpendicular to a radius originating from the rotation axis, which radius is included in the angular extent of the magnetized body around the rotation axis.

[0126] Fig.14 The example of considers a magnetized body having the shape of an angular sector comprising at least a first angular portion 10.1 and at least a second angular portion 10.2 different from each other around the main axis A', each angular portion having its own magnetization plane PM1, PM2.

[0127] In this case, the magnetized body has a magnetization whose magnetization vector is:

[0128] at any point of the first angular portion 10 . 1 of the magnetized body 10 , parallel to the first fixed magnetization plane PM1 ;

[0129] at any point of the second angular portion of the magnetized body, parallel to the second fixed magnetization plane PM2; and

[0130] In the considered magnetization plane there is a continuously variable direction that varies with the position of the point of the considered angular portion of the magnetized body along a direction perpendicular to the main axis A′.

[0131] In this case, it is then considered that different angular portions of the magnetized body each correspond to an associated magnetization plane.

[0132] It can be provided that, for each angular portion, the magnetization plane PM is perpendicular to the radius originating from the main axis A′ and included in the angular range of the angular portion under consideration.

[0133] By stipulating that the magnetization vector is parallel to the fixed magnetization plane, it can be understood that at each point of the magnetized body or the associated annular portion of the magnetized body, the magnetization vector is parallel to the plane. Therefore, the magnetization plane is a theoretical plane that indicates the orientation of the vector for all points of the magnetized body or the associated annular portion of the magnetized body. In the field of magnetic fields (especially the field of magnetization intensity of the magnetized body), the concept of parallelism must be explained with reference to conventional technology. On the one hand, it is known that the magnetization intensity is affected by edge effects, which can locally change the magnetization intensity near the outer surface of the magnetized body. At these points, the magnetization vector may not be strictly parallel to the magnetization plane as a theoretical plane. Similarly, it is known that homogeneity defects of magnetic materials can locally affect the magnetization intensity. Therefore, the magnetization plane must be understood as representing the magnetization intensity at each point of the magnetized body or the associated annular portion of the magnetized body, considered as a whole, while mainly considering points that are not affected by edge effects or obviously undesirable homogeneity defects, therefore especially points at the core of the magnetized body or the associated annular portion of the magnetized body.

[0134] The examples shown have shown the case where the magnetization plane is strictly parallel to the rotation axis A and / or the main axis A'. It is understood that the concept of a magnetization plane being strictly parallel or parallel to the rotation axis A and / or the main axis A' must also be evaluated here with reference to conventional techniques in the field of magnetic fields, in particular in the field of the magnetization intensity of the magnetized body. It should also be evaluated in comparison with the prior art, in which the magnetization plane is perpendicular to the rotation axis A and / or the main axis A'. It must also be evaluated with reference to the advantages and benefits of the invention, in particular the simplicity of manufacturing of the magnetized body and, as will be seen below, the compactness of the sensor system made of such a magnetized body in the radial direction relative to the rotation axis A and / or the main axis A'.

[0135] Furthermore, within the meaning of the present invention, a magnetization plane is considered strictly parallel to the axis under consideration if it forms an angle of less than 5 degrees with the axis of rotation A and / or the main axis A'. It is considered parallel to the axis under consideration if it forms an angle of inclination with the axis of rotation A and / or the main axis A' of less than 30 degrees, preferably less than 20 degrees. Under these conditions, the magnetization plane PM, PM1, PM2 of the magnetized body is considered parallel to the axis of rotation A and / or the main axis A'.

[0136] For the following description, an orthogonal reference system can be defined in:

[0137] The origin O' is a point of the main axis A', preferably the center of the magnetized body 10 along the direction of the main axis A',

[0138] Basis Vector and The directions of are arbitrary but are orthogonal to each other and are contained in a plane perpendicular to the main axis A' (and therefore perpendicular to the axis of rotation A),

[0139] Basis Vector is parallel to the main axis A' and can therefore be related to the basis vectors of the reference system of the second component 16 coincide.

[0140] This reference system is related to the magnetized body 10, so the basis vector and The direction of is related to the magnetized body 10. In the following example, the center O' of the reference system related to the magnetized body can coincide with the center O of the reference system related to the second component 16.

[0141] For convenience, the case is described more particularly in which the magnetized body comprises a single magnetized plane for its entire angular extent and in which this magnetized plane is perpendicular to the bisector of the angular extent of the magnetized body 10 around the main axis A'. In this case, it is advantageous to use the direction of the bisector of the angular extent of the magnetized body 10 around the main axis A' as the basis vector In this case, the magnetization plane PM is perpendicular to the basis vector direction, and any parallel plane PMi is represented by the vector The direction of the Figure 5A As shown, in a given plane PMi parallel to the magnetization plane, a point P(x i ,y,z) can be thus represented by its coordinates (x i ,y,z) definition, the value xi is the same for all points in a given plane PMi. In such a plane, the magnetization vector Its coordinates (m y ,m z ) or by its relative position to the basis vectors The orientation of the magnetization vector P can be defined by With basis vector The angle between yz The angle a yz The point P(x i ,y,z) is the orientation of the magnetization vector.

[0142] Magnetization vector has a continuously variable direction in the plane PMi that varies with the position of the considered point P of the magnetized body in the magnetization plane PMi along the direction Y perpendicular to the main axis. In this way, the function a yz(y) is a continuously varying function within the segment of the magnetized body contained in the plane PMi under consideration, since y varies with the point along the basis vector If there is a single angular portion covering the entire angular range and associated with a single magnetization plane, the property is valid over the entire range of the magnetized body; if there are several different angular portions, each corresponding to a magnetization plane, the property is valid within the considered angular portion.

[0143] Preferably, within the angular portion of the magnetized body 10 around the main axis A', corresponding to the magnetization plane under consideration, the orientation vector The orientation of has different values ​​for any position along the axis Y. Therefore, within the angular portion of the magnetized body 10 around the main axis A', the orientation vector The orientation of changes within an angular range of less than 360 degrees. On the other hand, in order to improve the accuracy of determining the angular position, it is preferred to use a magnetized body in which the orientation vector The orientation of changes continuously within a range of more than 180 degrees (preferably, more than 270 degrees) but less than 360 degrees.

[0144] Preferably, for a point of the considered angular portion of the magnetized body contained in the plane PMi, the magnetization vector All points with a given position in the magnetization plane PMi along the direction Y perpendicular to the main axis have a constant or almost constant direction. In this way, for a given value of y within the range of the segment of the magnetized body contained in the plane PMi considered, the function a yz (z) relative to a yz (y) is a constant or nearly constant function. However, the function a yz Variations of (z) are permitted. Such variations will preferably be included between angles of 0 and 30 degrees.

[0145] In some embodiments, the direction of the magnetization vector follows the direction of the considered point in the magnetization volume along the basis vector The function a varies linearly or almost linearly with the position in the direction of yz (z) is a continuous linear or almost linear function in the plane PMi considered.

[0146] exist Figure 5 and Figure 5A In the case of , if Ts refers to the spatial period of the variation, that is, two points (whose magnetization vectors have the same direction) are along the basis vector The distance between the two directions, expressed in units of coordinate y, varies linearly and depends only on the magnetic angle a in the direction y. yzThe expression for (z) will be written as:

[0147]

[0148] Preferably, in particular by implementing the magnetization method described below, the magnetization vector It will be constant or almost constant along the direction perpendicular to the magnetization plane PM.

[0149] For the case where the magnetized body comprises a single magnetized plane throughout its angular extent, in the reference system associated with the magnetized body 10 In this case, the expression for the magnetization vector will be:

[0150]

[0151] In actual implementation, function a yz (y) can be nonlinear and can also be used to:

[0152] Managing the edge effects of the magnetic field produced by the magnets;

[0153] Imposing the desired linear or (inversely) non-linear response of the sensor system.

[0154] In fact, a method is also proposed for producing a magnetized body for a system for determining relative angular positions, in particular for implementing the method according to the invention.

[0155] In the method, a body of magnetizable material having a shape as defined above is provided. The magnetizable material is in particular a ferromagnetic material, in particular a hard ferromagnetic, ferrimagnetic or antiferromagnetic material, which is capable of forming a permanent magnet after controlled magnetization. Such materials include alloys, such as alloys of neodymium, iron and boron (Nd2Fe14B), alloys of samarium and cobalt (SmCo5 and Sm2Co17), ferrite, and AlNiCo.

[0156] First of all, it is necessary to focus on the case where the magnetized body comprises a single magnetized plane over its entire angular extent. Figure 6 and Figure 7 As shown, a network 20 of parallel electric conductors 22 is arranged in the vicinity of the body 10 of magnetizable material, said network comprising several bundles 24 of parallel electric conductors, each bundle oriented along an axis perpendicular to the main axis A'. In a plane perpendicular to the main axis A, the orientation of the electric conductors (hereinafter referred to as magnetized conductors 22) is preferably included in an angular range defined by two radii R1 and R2 originating from the main axis A' and passing around it through an angular end of the magnetized body (thus, in the example shown, through the side 9).

[0157] The orientation of the magnetized conductor 22 will determine the preferred relative angular position of the magnetized body 10 with respect to the measuring unit 10, 11, the accuracy of the angular position obtained by the sensor system 1 being theoretically the best one. This position corresponds to the angular position on the magnetized body 10 defined by the radius originating from the main axis A' and having the orientation of the magnetized conductor 22. Moving away from the reference position increases the risk of reducing the measurement accuracy. In order to obtain the best accuracy over the entire angular travel of the sensor system 1, it may be of interest that the preferred angular position is arranged at half of the angular travel. In this case, it may be provided that the orientation of the magnetized conductor corresponds to the orientation of the bisector of the angular range of the magnetized body 10, or at least it is included in a limited range of orientations around the bisector. This limited range is, for example, a range of 15 degrees centered on the orientation of the bisector.

[0158] In a reference frame associated with a magnet, a "bundle 24 of magnetized conductors 22" refers to a group of magnetized conductors in which current flows in the same direction at a given time and the group of magnetized conductors is not separated by magnetized conductors 22 in which current flows in another direction. A bundle 24 may include a single magnetized conductor 22, or preferably, a plurality of magnetized conductors 22, for example, a bundle 24 includes a range of 4 to 40 magnetized conductors 22. Different bundles 24 may include different numbers of magnetized conductors 22.

[0159] In a bundle 24, some or all magnetized conductors 22 may adjoin one another. In this case, provision may be made that the magnetized conductors 22 are electrically insulated from one another, for example by an insulating sleeve. Conversely, one or several magnetized conductors 22 of a bundle 24 may be laterally spaced apart from other magnetized conductors of the same bundle 24, or all magnetized conductors 22 may be spaced apart from one another. A bundle 24 may include an outer envelope surrounding the magnetized conductors 22 of the bundle, which outer envelope is made, for example, of an electrically insulating material.

[0160] exist Figure 6 and Figure 7 In the example of FIG. 4 , four beams 24 have been shown. In two beams 24, the current flows in a first direction depending on the orientation of the magnetized conductors, while in the other two beams, the current flows in a second direction opposite to the first direction.

[0161] Preferably, the magnetized conductor 22 consists of a wire or a rod made of a conductive material (eg copper) extending according to an orientation.

[0162] The beams 24 are laterally offset from each other along an offset direction which is perpendicular to their orientation and perpendicular to the main axis A'. This offset direction is parallel to the magnetization plane to be created. Figure 7 , Fig.10 and Fig.11In the example shown, the beams 24 are aligned along the offset direction. However, some beams 24 may additionally be offset from other beams along a direction perpendicular to the magnetization plane to be created. They are preferably arranged in the immediate vicinity of the body of magnetizable material, preferably in the immediate vicinity of the end face (thus the upper end face 5 in the illustration) to which the measuring units 11, 12 are to be arranged in the sensor system 1.

[0163] Typically, the beam is positioned less than 10 mm from the end face or less than 5 mm from the end face.

[0164] Said method naturally involves the flow of an electric current in the bundles of magnetized conductors 22 , the direction of which, at a given time (eg the time of maximum current intensity), is the same in all magnetized conductors 22 of the same bundle 24 , and is opposite in two adjacent bundles 24 .

[0165] Therefore, through the flow of this current, one or several output beams 24 and one or several input beams 24 can be distinguished, wherein the one or several output beams form a group of output beams, wherein, at a given time (for example, the time when the current intensity is maximum), the current flows along a first direction, and the one or several input beams form a group of input beams, wherein, at the same given time, the current flows along a second direction opposite to the first direction.

[0166] In this way, the current flowing in the beam 24 is able to generate around the network 20 and therefore in the body of magnetizable material a magnetizing magnetic field suitable for magnetizing the body of magnetizable material. In particular, this current must have a maximum sufficient intensity value. By arranging the beam 24 perpendicular to the main axis A' and by alternating the output beam and the input beam, a magnetic field suitable for imparting a magnetization intensity as described above to the body made of magnetizable material can be generated.

[0167] In particular, the magnetic field generated by the network of magnetized conductors is preferably capable of magnetically saturating the magnetizable material at any point thereof.Once so magnetized, the body made of magnetizable material can be used as a body of magnetic material 10 in the method and sensor system 1 according to the invention.

[0168] To this end, in particular the following parameters can be adjusted:

[0169] the intensity of the current in the bundle and therefore in the conductor, especially taking into account the maximum intensity;

[0170] Conductor bundle density;

[0171] relative positioning of bundles and conductors in the bundles;

[0172] the number of conductors in each bundle;

[0173] the distance of the beam relative to the body of magnetizable material (in particular relative to the front envelope surface 3 of the magnet, and relative to the upper end surface) along the main axis;

[0174] wait.

[0175] exist Figure 7 In the example of , the network of conductors comprises two output beams and two input beams arranged alternately. Within the limits defined by the side 9 of the magnetized body 10, the first output beam and the first input beam are symmetrically arranged on either side of a symmetry plane of the magnetized body containing the main axis A'. Outside the limits defined by the side 9 of the magnetized body, the second output beam and the second input beam are symmetrically arranged on either side of a symmetry plane of the magnetized body containing the main axis A'.

[0176] exist Fig.10 In the example of , the network of conductors comprises only one output and one input bundle, which are arranged symmetrically on either side of a symmetry plane of the magnetized body containing the main axis A'. In the example, they are arranged within the limits defined by the side faces 9 of the magnetized body.

[0177] exist Fig.11 In the example of , the network of conductors comprises one output beam and two input beams. The opposite configuration is possible, i.e. there may be one input beam and two output beams. A single beam (here the output beam) is arranged on a symmetry plane of the magnetized body containing the main axis A'. Two beams (here the two input beams) along the same direction are symmetrically arranged on either side of the symmetry plane of the magnetized body containing the main axis A'. In the example, they are arranged at the limits defined by the side 9 of the magnetized body.

[0178] It should be noted that the different bundles 24 do not necessarily comprise the same number of conductors. For example, the number of conductors in each bundle 24 may decrease when moving away from the plane of symmetry of the magnetized body containing the main axis A'.

[0179] In output bundle groups 24 on the one hand and input bundle groups 24 on the other hand, provision can be made that several bundles 24 or all bundles 24 are powered in parallel. Likewise, in a given bundle 24, provision can be made that several magnetized conductors 22 or all magnetized conductors 22 are powered in parallel.

[0180] Preferably, however, provision will be made that several or all bundles 24, including output and input bundles, are electrically connected in series. Provision will be made that several or all magnetizing conductors 22, including output and input magnetizing conductors, are electrically connected in series to form one or several magnetizing coils.

[0181] Thus, it can be provided that the magnetized conductors 22 of a bundle are formed by a segment of at least one coil winding for a conductor, along which the magnetized conductor 22 of at least one output bundle, a connecting segment, a magnetized conductor 22 of an input bundle, a further connecting segment and a further magnetized conductor 22 of an output bundle follow one another repeatedly. Thus, within a network, all magnetized conductors 22 can be combined together into a single coil winding, two coil windings or more than two coil windings.

[0182] In another embodiment (not shown), the network of conductors may be formed by a grid comprising a first rod connected to a first potential, located on one side of a body made of magnetizable material, and a second rod connected to a second potential, located on the other side of the body made of magnetizable material. Each conductor of the network may then take the form of a linear segment, the length of which will correspond to the distance between the rods, each conductor extending between two rods and connected by its two ends to a first connecting rod and a second connecting rod, respectively.

[0183] The magnetized conductor 22 has a length according to its orientation, which extends between two supply heads, which can be constituted, for example, by connecting segments in the framework of a winding, or by connecting rods in the framework of a bundle formed by a grid. In the supply heads, currents can flow in a direction transverse or substantially transverse to the orientation of the conductors. It is desirable to limit the magnetic influence of these currents in order to limit the disturbance of the magnetization of the body of magnetizable material, and it is therefore desirable for the magnetized conductor to have a sufficient length to achieve this purpose. Therefore, according to the orientation of the magnetized conductor 22, the magnetized conductor 22 will have a length greater than the extent of the body of magnetizable material.

[0184] Fig.14 Schematically shown is a method for manufacturing a magnetized body comprising a first angular portion 10.1 and at least a second angular portion 10.2 different from each other around a main axis A', the magnetized body having a magnetization whose magnetization vector is such that:

[0185] At any point of the first angular portion 10 . 1 of the magnetized body 10 , the magnetization vector is parallel to the first fixed magnetization plane PM1 ,

[0186] At any point of the second angular portion 10.2 of the magnetized body, the magnetization vector is parallel to the second fixed magnetization plane PM2, and

[0187] In the magnetization plane PM1 , PM2 under consideration the magnetization vector has a continuously variable direction that varies with the position of the point of the magnetized body of the angular portion under consideration in the magnetization plane under consideration along a direction perpendicular to the main axis A′.

[0188] To this end, the method provides a first network 20.1 of parallel electric conductors extending facing a first portion of the body of magnetizable material. The first network comprises several bundles 24.1 of parallel electric conductors 22 having an orientation X1 perpendicular to the main axis A' and parallel to a first directrix radius originating from the main axis A' and included in the angular extent of the considered first angular portion 10.1 of the magnetizable body.

[0189] The first network includes at least one output bundle and at least one input bundle.

[0190] A second network 20.2 of parallel electric conductors is also provided, which extends facing a second portion of the body of magnetizable material different from the first portion. The bundles 24.2 of parallel electric conductors 22 of the second network 20.2 are oriented along a second orientation X2, which is perpendicular to the main axis (A') and parallel to a second directrix radius originating from the main axis (A') and included in the angular range of the second angular portion 10.2 under consideration.

[0191] The second network has at least one output bundle and at least one input bundle.

[0192] By producing different magnetization planes in the two angular sections, it is possible to obtain optimal accuracy over the entire angular travel of the sensor system 1, in particular for sensor systems with magnetized bodies with a large angular range. In order to further optimize the accuracy, it can be provided that the orientation of the magnetized conductors in each network 20.1, 20.2 corresponds to the orientation of the bisector of the angular range of the respective angular section 10.1, 10.2 of the magnetized body 10, or at least it is included in a limited range of orientations around the bisector. This limited range is, for example, a range of 15 degrees angularly centered on the orientation of the bisector.

[0193] Of course, the principle of having several magnetization planes (as mentioned above Fig.14 As described above, having two different magnetization planes for two different angular sections, can be varied to have three, four or more different magnetization planes for the same number of angular sections.

[0194] As mentioned above, in the example shown, the sensor system 1 may comprise a single measuring unit, or may comprise at least two measuring units. In the case of two measuring units, the measuring points C1 and C2 of the first unit 11 and the second unit 12 are preferably arranged in the same plane perpendicular to the axis of rotation A, axially offset relative to the upper end face 5 of the magnetized body 10 in the direction of the axis of rotation A. In the sensor system 1, the unit 11 or each of the two measuring units 11, 12 determines at the respective measuring points C1, C2 a value representative of the orientation of the magnetic field B generated by the magnetized body 10 at these measuring points C1, C2. Each measuring unit 11, 12 transmits at least two electrical signals (for example digital and / or analog signals) representing respectively the main component and the secondary component of a vector (said vector representing the magnetic field B induced by the magnetized body 10 at the measuring point of the unit under consideration), said main component and secondary component respectively along the main measuring axes AP1, AP2 and along the secondary measuring axes AS1, AS2, the main measuring axes and the secondary measuring axes being orthogonal to each other and contained in a plane parallel to the axis of rotation A. Of course, the invention covers embodiments making it possible to implement measurement cells with higher capacity, for example delivering more than two signals and / or signals representing for example more than two components of a vector representing the magnetic field B induced by the magnetized body 10 at the measurement point of the cell under consideration.

[0195] In the example that will be described in more detail below, for the determination of the relative angular position, it will be possible to use only two electrical signals representing respectively the primary and secondary components of the vector representing the magnetic field B induced by the magnetized body 10 at the measurement point of the cell under consideration, even if the cell used is capable of giving three components. These two components therefore define a two-dimensional measurement plane for each cell.

[0196] In an exemplary embodiment comprising a single measuring unit 11, as Figure 1A As shown, the main measurement axis AP1 is preferably parallel to the rotation axis A and perpendicular to the radial basis vector So parallel to the basis vector It is therefore tangential with respect to the rotation about the rotation axis A. Otherwise, preferably, the measurement plane is perpendicular to the radial basis vector The radial basis vectors form radii originating from the axis A and passing through the measurement points.

[0197] exist Figure 1B In the exemplary embodiment shown, comprising two units 11, 12, the measuring planes of the two measuring units 11, 12 are parallel to each other and even coincide. For this purpose, the main measuring axes AP1, AP2 of the two measuring units 11, 12 are chosen to be contained in the same plane parallel to the rotation axis A and therefore in the same plane as that defined by the base vectors and Furthermore, in the exemplary embodiment comprising two units 11, 12, the main measuring axes AP1, AP2 of the two measuring units 11, 12 are parallel to each other and to the axis of rotation A and thus to the base vector Otherwise, the measuring planes of the measuring units 11 , 12 are preferably parallel to the axis of rotation A.

[0198] Furthermore, in both examples, for a reference position between the first component 14 and the second component 16 (that is to say, for a reference position between the magnetized body 10 and the cells 11, 12), the measurement unit or the measurement plane of each of the measurement units 11, 12 may be parallel to the magnetization plane of the magnetized body 10. This reference position is preferably included in the angular travel between the first component 14 and the second component 16, that is to say, in the relative angular travel between the magnetized body 10 and the cells 11, 12.

[0199] exist Figure 1A In the exemplary embodiment shown, comprising a single unit 11, it has been provided that, in the case of the use of the above-described magnetization method, the reference position for which the measuring plane of the unit is strictly parallel to the magnetization plane corresponds to a position in which, during the magnetization of the magnetized body, the measuring unit 10 is arranged facing a preferred position determined by the orientation of the electrical conductor. Figure 1B In the exemplary embodiment shown, comprising two units 11, 12, a reference position has been provided, for which the measuring plane of the unit is strictly parallel to the magnetization plane, corresponding to a position in which, during magnetization of the magnetized body, the measuring units 10, 11 are arranged symmetrically with respect to a preferred position determined by the orientation of the electrical conductor, when using the above-described magnetization method.

[0200] In the two examples shown, the reference position, for which the measuring plane of the unit is strictly parallel to the magnetization plane, is set at half the angular travel. Figure 2A It is shown more specifically in FIG. 1 that for an exemplary embodiment comprising two units 11, 12, it can be provided that the reference position is included in a limited range around the bisector of the angular stroke. The limited range is, for example, a range of 15 degrees centered on the orientation of the bisector. In other variants, the reference position can correspond to one end of the angular stroke.

[0201] In an exemplary embodiment comprising a single unit 11 , the first measuring point C1 of the first measuring unit 11 is arranged at a distance R from the rotation axis A. Preferably for the entire angular travel of the sensor system, this distance is such that the measuring point C1 is arranged facing the upper end face 5 of the magnetized body.

[0202] In an exemplary embodiment comprising two units 11 , 12 , a first measuring point C1 of the first measuring unit 11 and a second measuring point C2 of the second measuring unit are arranged at an equal distance R from the rotation axis A. Preferably, this distance is such that the measuring points C1 and C2 are also arranged facing the upper end face 5 of the magnetized body for the entire angular travel of the sensor system.

[0203] In both cases, therefore, the measuring point of the measuring unit can be arranged at a distance R from the axis of rotation A which is smaller than the radius of the front envelope surface 3 of the magnetized body, which radius forms the outer radius of the magnetized body.

[0204] This arrangement is particularly advantageous since it allows the spatial requirement of the sensor system in the radial direction relative to the axis of rotation A to be limited.

[0205] Advantageously, in a system of two units, as shown, two measuring points can be arranged in positions spaced apart by a non-zero fixed angle 2δ around the axis of rotation A, said non-zero fixed angle being strictly less than an angle of 90 degrees. Preferably, this spacing angle 2δ is included in the range of 1.5 to 30 degrees, corresponding to a distance between the two measuring points, said distance being included, for example, between 1 mm and 5 mm. The measuring points C1 and C2 of the first unit 11 and the second unit 12 are different points, which are spaced apart from each other around the axis of rotation A. The minimum distance between the two measuring points must be such that the representative values ​​of the magnetic field generated by the magnetized body at these two points differ by a deviation which is greater than the resolving power of the measuring unit. In other words, the first measuring unit and the second measuring unit must not deliver the same value of the vector representing the magnetic field, due to their respective measurements at these two points.

[0206] Furthermore, in this example, the first measuring unit 11 and the second measuring unit 12 are preferably arranged on the second component 16 such that the primary measuring axes AP1, AP2 of the first measuring unit 11 and the second measuring unit 12 are parallel to each other, and such that the secondary measuring axes AS1, AS2 of the first measuring unit 11 and the second measuring unit are parallel to each other. In other words, the two measuring units 11, 12 (in particular their measuring elements) are arranged parallel to each other. Preferably, for each unit, one of the primary measuring axes AP1, AP2 or the secondary measuring axes AS1, AS2 is parallel to the rotation axis A.

[0207] In the example shown, the primary measuring axes AP1, AP2 of the first measuring unit 11 and the second measuring unit 12 are oriented vectorially in the same way, and the secondary measuring axes AS1, AS2 of the first measuring unit and the second measuring unit are also oriented vectorially in the same way. In other words, the two measuring units 11, 12 (in particular their magnetosensitive elements) are arranged in the same way. However, the primary measuring axes AP1, AP2 of the first measuring unit 11 and the second measuring unit 12 and / or the secondary measuring axes AS1, AS2 of the first measuring unit and the second measuring unit can be oriented vectorially along two opposite paths in the same direction. In this case, however, it will be necessary to express the algebraic values ​​of the primary and secondary components in the same way on the same vector basis, and therefore to take into account the opposite value of one of the two algebraic values ​​delivered by the units.

[0208] As in the illustrated exemplary embodiment comprising two units 11, 12, the first measuring unit 11 and the second measuring unit 12 may be arranged on the second component 16 such that a primary measuring axis of the first measuring unit and the second measuring unit or a secondary measuring axis of the first measuring unit and the second measuring unit is:

[0209] Oriented perpendicularly to the direction of the bisector of the angular deviation between the two measuring points C1 , C2 measured about the axis of rotation A in a plane perpendicular to the axis of rotation A,

[0210] Oriented perpendicularly to the axis of rotation A.

[0211] Therefore, if Figure 2B As shown in more detail in FIG. 1 , it can be provided that the first measuring unit 11 and the second measuring unit 12 are arranged on the second component 16 such that the main measuring axes AP1 , AP2 of the first measuring unit 11 and the second measuring unit 12 are oriented as follows:

[0212] perpendicular to the direction of the bisector of the angular deviation 2δ between the two measuring points C1 , C2 , the angular deviation being measured about the axis of rotation in a plane perpendicular to the axis of rotation A, and

[0213] Perpendicular to the axis of rotation A.

[0214] Therefore, Figures 2 to Figure 4 The main measurement axes AP1, AP2 of the first and second measurement units are shown by the distance from the base vector The angle is determined by the radial basis vector The orientation of the radial basis vector is chosen to pass through the measurement point C1 of the first unit. It should be noted that this angle δ corresponds to half of the angular deviation 2δ between the two measurement points C1, C2 measured around the rotation axis A in a plane perpendicular to the rotation axis A. In addition, the secondary measurement axes AS1, AS2 of the first and second measurement units are along the basis vectors However, other orientations are also possible.

[0215] There are many commercially available units that allow these measurements to be obtained.

[0216] Thus, an example of a unit that can be used in the present invention may implement the component "MLX90365 Triaxis position sensor IC", which is sold by Melexis NV, Rozendaalstraat 12, B-8900 Ieper, Belgium, and which is described in detail in the following document: "MLX90365 Triaxis position sensor IC data", revision 5.8, dated 11.01.2016. Other references of the same manufacturer may also be used, such as reference MLX90333 or MLX90364.

[0217] This type of measuring unit 11, 12 ensures the measurement of the magnetic field at a single point by minimizing the number of integrated circuits and simplifying the production by reducing the number of components (each of which introduces tolerances related to mounting uncertainties). Depending on the spatial resolution of the position measurement delivered by the sensor, the concept of measurement at a single point can be evaluated. Each measuring unit 11, 12 can, for example, include a magnetosensitive unit generally composed of at least two magnetosensitive elements, which are very close to each other until they are considered to be at the same point, and whose output may be used by the calculation unit of the measuring unit. Very often, the magnetosensitive unit and the calculation unit are part of the same electronic component, which allows to reduce costs and improve the reliability of the sensor. It is conceivable to integrate the two measuring units 11, 12 into the same electronic component, which may include a calculation unit common to the two units. However, within the framework of the invention, it can be provided that the two units are equipped with a communication unit for transmitting information to a remote calculation unit, the communication unit being housed, for example, in an electronic control unit (ECU) or a computer.

[0218] With this type of unit, at each measurement point C1, C2, at least two components By, Bz of the vector representing the magnetic field B generated by the magnetized body 10 in an orthogonal reference system can be obtained. The two reference systems have different origins at the measurement points C1, C2 considered, respectively, but have the same basis vectors. Naturally, the unit transmits electrical signals representing the components of the vector of the magnetic field B along the main measurement axis AP1 and along the secondary measurement axis AS1. The first unit 11 allows in particular to obtain, in the measurement plane, along the main measurement axis AP1, a first main component By1 representing the vector of the magnetic field B at the point C1, and along the secondary measurement axis AS1, a first secondary component Bz1 representing the vector of the magnetic field B generated by the magnetized body at the point C1. The second unit 12 allows in particular to obtain, in the measurement plane, along the main measurement axis AP2, a second main component By2 representing the vector of the magnetic field B at the point C2, and along the secondary measurement axis AS2, a second secondary component Bz2 representing the vector of the magnetic field B generated by the magnetized body at the point C2. By simple trigonometric calculations, these components can be expressed in terms of and / or Indicated in.

[0219] It will be noted that if the measuring plane is not strictly parallel to the magnetization plane, the unit will be measured in projection. This lack of parallelism is found due to the relative rotation of the magnetized body with respect to the unit. This lack of parallelism may also be caused by an inclination between the measuring plane and the magnetization plane around an axis, the axis being perpendicular to the axis of rotation and / or the main axis A' and perpendicular to the radius originating from this axis. This inclination is equal to the difference in inclination between the measuring plane and the magnetization plane relative to the axis of rotation and / or the main axis A'. In the present invention, if the inclination difference is less than 30 degrees, preferably less than 20 degrees, this inclination difference has almost no effect. In this case, it can be considered that the measuring plane and the magnetization plane are parallel. In the present invention, if the inclination difference is less than 5 degrees, this inclination difference will be negligible, in which case it can be considered that the measuring plane and the magnetization plane are strictly parallel.

[0220] Within the framework of the invention, it is provided to determine a value representative of the relative angular position of the two components 14, 16 over an angular stroke about the axis of rotation (A). This angular position can be determined by the radial basis vectors associated with the first component 14 (e.g., arbitrarily selected as the one passing through the measurement unit or the measurement point of the first measurement unit, depending on the number of units) and the basis vectors associated with the second component The angle θ between them is represented by .

[0221] like Figure 8 As shown, it should therefore be understood that the method 100 according to the invention comprises a step 110 of providing the first component 14 with a magnetized body 10 , as described above.

[0222] A differential approach to implementing the two units is described in more detail here.

[0223] The method comprises a step 120 of equipping the second component 16 with a first measuring unit 11 at a first measuring point C1 and equipping the second component with a second measuring unit 12 at a second measuring point C2 according to the above-described manner.

[0224] In the method, each measuring unit transmits 130 at least two electrical signals representing respectively a primary component By1, By2 and a secondary component Bz1, Bz2 of a vector representing the magnetic field B(1), B(2) generated by the magnetized body 10 at the measuring point C1, C2 of the unit under consideration, respectively along the primary measuring axes AP1, AP2 and along the secondary measuring axes AS1, AS2, the primary and secondary measuring axes forming a measuring plane parallel to the axis of rotation A.

[0225] In the method, the first measurement unit 11 and the second measurement unit 12 may be arranged on the second component 16 such that the primary measurement axes AP1, AP2 of the first measurement unit and the second measurement unit are parallel to each other (preferably vector-oriented in the same way), and such that the secondary measurement axes AS1, AS2 of the first measurement unit and the second measurement unit are parallel to each other (preferably vector-oriented in the same way). In other words, the measurement planes of the two units are parallel. If this is not the case, a change of reference frame will be operated to represent the components in the same reference.

[0226] By using a sensor system 1 with two measuring units as described above, the above-described steps of the method will be advantageously implemented.

[0227] In step 150, the method determines a value representing the relative angular position θ between the two components by determining 140 an original angle "gamma", the tangent of which is a function of the differential composition of the components By1, By2, Bz1, Bz2 determined by the unit. This original angle "gamma" is equal to or represents the angular orientation of the magnetic field vector generated by the magnetized body at the measurement point. This original angle is sometimes referred to as the "magnetic angle". The differential composition can in particular be an algebraic ratio between a value representing the difference of the first components By1, By2, which may be weighted, on the one hand, and a value representing the difference of the second components Bz1, Bz2, which may be weighted, on the other hand.

[0228] According to one embodiment of the difference method, an original angle is calculated whose tangent is a function of the ratio between the difference of the secondary component on the one hand and the primary component on the other hand measured by the two units 11 , 12 for a given relative angular position.

[0229] Thus, the method comprises one or more calculation steps which may be implemented in a calculation unit which is integrated into the sensor system 1 or remotely, for example in an electronic control unit or a computer. The calculation unit typically comprises one or several memory modules, at least one processor, a data input / output module and possibly a communication module. The calculation steps of the method are typically implemented by a computer program comprising corresponding instructions and stored in a memory module.

[0230] Therefore, in this example, a value ΔB is calculated. y , which represents the difference between the first principal component By1 and the second principal component By2 measured at points C1 and C2, respectively. In general, this difference can be written in the form of a function (e.g., a linear or affine function):

[0231] ΔB y =f y (By1-By2)

[0232] For example, it may have:

[0233] ΔB y =a y *(By1-By2)+c y

[0234] In the simplest way, it can have:

[0235] ΔB y = By1 - By2 (1)

[0236] Likewise, a value ΔB is calculated z , which represents the difference between the first secondary component Bz1 and the second secondary component Bz2 measured at points C1 and C2, respectively. In general, this difference can be written in the form of a function (e.g., a linear or affine function):

[0237] ΔB z =f z (Bz1-Bz2)

[0238] For example, it may have:

[0239] ΔB z =a z *(Bz1-Bz2)+c y

[0240] In the simplest way, it can have:

[0241] ΔB z = Bz1 - Bz2 (2)

[0242] In this case, the invention provides for determining the original angle gamma as a circular arc whose tangent represents the ratio between the difference of the secondary component on the one hand and the difference of the primary component on the other hand, which ratio may be the ratio ΔB z / ΔB z , or the inverse ratio ΔB y / ΔB z Depending on the ratio chosen, you will obtain the original angle gamma or the remaining angle (90°-gamma), from which you can easily return to the desired original angle.

[0243] Therefore, the value of this original angle gamma can be written as a function:

[0244] gamma = Arctan{f[ΔB z / ΔB y ]} or gamma = Arctan{f[ΔB y / ΔB z ]}

[0245] That is, for example:

[0246] gamma = Arctan{f[f z (Bz1-Bz2) / f y (By1-By2)]}

[0247] In this equation, the function f can be considered as a filter function of the measured value. In the simplest way, it can be:

[0248] gamma = Arctan {K yz x [(Bz1 - Bz2) / (By1 - By2)]} (3)

[0249] Among them, K xy is the theoretically calculated value of the angle of the magnetic field in the measurement plane of the unit, which is equal to 1, but sometimes it is advantageous to use another value to compensate for measurement deviations.

[0250] In one embodiment with a single unit, the original angle can be obtained very easily, for example in the following form:

[0251] gamma = Arctan{K yz x[(Bz1-Bz2) / (By1-By2)]}

[0252] The original angle corresponds to the magnetic field orientation at the measuring point, or represents the magnetic field orientation at the measuring point. Due to the fact that the magnetization intensity of the magnetized body is variable as described above, the magnetic field generated by the magnetized body outside the magnetized body also has a variable orientation. By ensuring that the orientation of the magnetic field vector at the measuring point on the relative angular travel of the two components 14, 16 changes over an angular range of less than 360 degrees, the relationship between the original angle and the relative angular position between the two components can be determined, which can be a one-to-one relationship if possible. This relationship can be determined, for example, by calculation, by simulation or by learning.

[0253] To illustrate Figure 5 The operation of the sensor shown in Fig. 12A , Fig. 12B as well as Fig.13A and Fig. 13B The signals that can be obtained with this sensor are shown in . These results were obtained by simulation.

[0254] The figures show the simple field signal and the differential field signal over a travel of 65 degrees, respectively, for a configuration with one measuring unit and for a configuration with two measuring units, for an angular position sensor with the following parameters:

[0255] Internal radius of the body: 15.5mm

[0256] Magnetized outer radius: 21.5mm

[0257] Measuring radius: 18.5mm

[0258] Angular range of magnetization: 78°

[0259] Thickness of magnet: 4mm

[0260] Measuring air gap: 1.7mm.

[0261] Fig. 12A Represents the signals By and Bz measured by the measuring unit at a point in the middle of the rotational travel. Fig. 12B Indicates that through Fig. 12A The angle is obtained by calculating the arc tangent of the ratio By / Bz from the signal.

[0262] Fig.13A = represents the differential signals By2-By1 and Bz2-Bz1 obtained from the magnetic field components at points C1 and C2, which are on either side of the middle of the rotation stroke in the tangential direction (that is, at Figure 2A and Figure 2B ) are 0.95 mm apart. Fig. 13B Indicates that through Fig.13AThe angle is obtained by calculating the arc tangent of the ratio (Bz2-Bz1) / (By2-By1) of the differential signal.

[0263] The advantage of implementing a single unit based measurement is that it is simple and generally requires less effort to have a sufficient measuring field (magnetic field).

[0264] Methods based on two cells operating in differential mode have the advantage of being more robust with respect to external magnetic fields, however, it may be difficult to obtain a sufficient measurement signal (magnetic field difference).

[0265] The invention allows obtaining a varying magnetic field over the travel of the sensor, which increases the accuracy of the sensor and generally offers the possibility of using differential methods.

[0266] The invention is not limited to the examples described and represented, since various modifications are possible without departing from its framework.

Claims

1. A method for determining the relative angular position of a first component (14) relative to a second component (16) over an angular travel about an axis of rotation (A), wherein: The first component is provided with a magnetized body (10) in the shape of a curved angular sector about the rotation axis (A), the angular sector comprising several consecutive angular portions or a single angular portion about the rotation axis (A), the magnetized body having a magnetization at any point of at least one angular portion of the magnetized body, the magnetization vector of which is: a fixed magnetization plane parallel to the corner portion of the magnetized body, and having a continuously variable direction in the magnetization plane that varies with the position of a point of the magnetized body in the magnetization plane along a direction perpendicular to the rotation axis (A); The second component is equipped with at least a first measuring unit (11) at a first measuring point (C1) which transmits two electrical signals representing respectively a primary component (By1) and a secondary component (Bz1) of a magnetic field generated by the magnetized body (10) in the measuring plane at the first measuring point (C1) of the unit under consideration, For a given relative angular position (θ), the method determines a value (θ) representative of the relative angular position between the two components as a function of the component measured by the first measurement unit (11); Characterized in that the magnetization plane (PM) of the magnetized body is parallel to the rotation axis (A).

2. The method according to claim 1, characterized in that The magnetized body (10) comprises a single angular portion, the magnetized body having a magnetization at any point of the magnetized body, the magnetization vector of the magnetization being: a single fixed magnetization plane parallel to the magnetized body, and In the magnetization plane there is a continuously variable direction that varies with the position of a point of the magnetized body along a direction perpendicular to the axis of rotation (A).

3. The method according to claim 2, characterized in that The magnetization plane (PM) is perpendicular to a radius originating from the rotation axis (A) and included in the angular extent of the magnetized body about the main axis (A′), said radius being oriented along a bisector of the angular extent or angular travel of the magnetized body.

4. The method according to claim 1, characterized in that: The magnetized body (10) comprises at least a first angular portion and at least a second angular portion different from each other around the rotation axis (A), the magnetized body having a magnetization whose magnetization vector: At any point of the first angular portion of the magnetized body, parallel to the first fixed magnetization plane, at any point of the second angular portion of the magnetized body, parallel to the second fixed magnetization plane, and In the considered magnetization plane, it has a continuously variable direction that varies with the position of a point of the considered angular portion of the magnetized body in the considered magnetization plane along a direction perpendicular to the rotation axis (A).

5. The method according to claim 4, characterized in that For each angular portion, the magnetization plane (PM) is perpendicular to the radius originating from the axis of rotation (A) and included in the angular range of the angular portion considered.

6. The method according to any one of claims 1 to 5, characterized in that The second component is provided with a second measuring unit (12) at a second measuring point (C2), which transmits two electrical signals representing respectively a main component (By2) and a secondary component (Bz2) of the magnetic field generated by the magnetized body (10) in the measuring plane at the second measuring point (C2) of the component under consideration, and wherein, for a given relative angular position (θ), the method determines a value (θ) representing the relative angular position between the two components by determining an original angle (gamma), the tangent of which is a function of the difference between the components measured by the first measuring unit (11) and the second measuring unit (12).

7. The method according to claim 6, characterized in that The first measuring unit (11) and the second measuring unit (12) are arranged on the second component such that their primary measuring axes (AP1) are parallel to each other and their secondary measuring axes (AS2) are parallel to each other.

8. The method according to claim 6, characterized in that The method determines a value (θ) representing the relative angular position between two components by determining an original angle (gamma), the tangent of which is a secondary component (ΔB) measured by a first measuring unit (11) and a second measuring unit (12) for a given relative angular position (θ). z ) and the other main component (ΔB y ) is a function of the ratio of the differences between them.

9. The method according to claim 6, characterized in that The first measuring point (C1) of the first measuring unit and, where appropriate, the second measuring point (C2) of the second measuring unit are arranged at a distance (R) from the rotation axis (A) while being offset from the magnetized body in the direction of the rotation axis (A), the distance being smaller than the radius of the outer cylindrical surface of the magnetized body.

10. The method according to any one of claims 1 to 5, characterized in that The magnetized body has the shape of a segment of a tubular sector, said shape being a cylinder of revolution about a main axis (A').

11. The method according to any one of claims 1 to 5, characterized in that The magnetized body (10) has the shape of a segment of an angular sector of a disk, said shape being a cylinder of revolution about a main axis (A').

12. The method according to any one of claims 1 to 5, characterized in that The measuring plane ((AP1, AS1), (AP2, AS2)) of one or more of the measuring units is parallel to the rotation axis (A).

13. A sensor system for determining the relative angular position of a first component (14) relative to a second component (16) over an angular travel about an axis of rotation (A), the system comprising: A magnetized body (10) in the shape of a curved angular sector around a main axis (A') parallel to the rotation axis (A), the angular sector comprising several consecutive angular sections or a single angular section around the main axis (A'), and the magnetized body (10) having a magnetization at any point of at least one angular section of the magnetized body, the magnetization vector of the magnetization being: a fixed magnetization plane parallel to the corner portion of the magnetized body, and having a continuously variable direction in the magnetization plane that varies with the position of a point of the magnetized body in the magnetization plane along a direction perpendicular to the rotation axis; a first measuring unit (11) at a first measuring point (C1) which delivers two electrical signals representing respectively a primary component (By1) and a secondary component (Bz1) of a magnetic field generated by the magnetized body (10) in the measuring plane at the first measuring point (C1) of the unit under consideration, a second measuring unit (12) at a second measuring point (C2) which delivers two electrical signals representing respectively a primary component (By2) and a secondary component (Bz2) of the magnetic field generated by the magnetized body (10) in the measuring plane at the second measuring point (C2) of the unit under consideration; Characterized in that the magnetization plane of the magnetized body is parallel to the rotation axis (A).

14. The sensor system according to claim 13, characterized in that The magnetized body (10) comprises a single angular portion, the magnetized body having a magnetization at any point of the magnetized body, the magnetization vector of the magnetization being: a single fixed magnetization plane parallel to the magnetized body, and It has a continuously variable direction in the magnetization plane that varies with the position of a point of the magnetized body in the magnetization plane along a direction perpendicular to the main axis (A′).

15. The sensor system according to claim 14, characterized in that The magnetization plane is perpendicular to a radius originating from the main axis (A′) and included in the angular extent of the magnetized body around the main axis (A′), the radius being oriented along a bisector of the angular extent or angular run of the magnetized body.

16. The sensor system according to claim 13, characterized in that The magnetized body (10) comprises at least a first angular portion and at least a second angular portion different from each other around the main axis (A'), the magnetized body having a magnetization whose magnetization vector is: At any point of the first angular portion of the magnetized body, parallel to the first fixed magnetization plane, at any point of the second angular portion of the magnetized body, parallel to the second fixed magnetization plane, and It has a continuously variable direction in the considered magnetization plane that varies with the position of a point of the considered angular portion of said magnetized body in the considered magnetization plane along a direction perpendicular to said main axis (A′).

17. The sensor system according to claim 16, characterized in that For each angular portion, the magnetization plane (PM) is perpendicular to the radius originating from the main axis (A′) and included in the angular range of the angular portion under consideration.

18. The sensor system according to any one of claims 13 to 17, characterized in that The system comprises a second measuring unit (12) at a second measuring point (C2) which delivers two electrical signals representing respectively a main component (By2) and a secondary component (Bz2) of a magnetic field generated by the magnetized body (10) in the measuring plane at the second measuring point (C2) of the unit under consideration, and wherein, for a given relative angular position (θ), the sensor system determines a value (θ) representing the relative angular position between the two components by determining an original angle ("gamma") whose tangent is a function of the difference between the components measured by the first measuring unit (11) and the second measuring unit (12).

19. The sensor system according to claim 18, characterized in that The first measuring unit (11) and the second measuring unit (12) are arranged so that their primary measuring axes (AP1) are parallel to each other and so that their secondary measuring axes (AP2) are parallel to each other.

20. The sensor system according to claim 18, characterized in that The system comprises a calculation unit programmed to determine a value (θ) representative of the relative angular position between the two components by determining an original angle (gamma) whose tangent is the difference (ΔB) of the secondary components measured by the first measuring unit (11) and the second measuring unit (12) for a given relative angular position (θ). z ) and the difference between the main components on the other hand (ΔB y ) is a function of the ratio between them.

21. The sensor system according to any one of claims 13 to 17, characterized in that The first measuring point (C1) of the first measuring unit and, where appropriate, the second measuring point (C2) of the second measuring unit are arranged at a distance (R) from the rotation axis (A) while being offset from the magnetized body in the direction of the rotation axis (A), the distance being smaller than the radius of the outer cylindrical surface of the magnetized body.

22. The sensor system according to any one of claims 13 to 17, characterized in that The magnetized body has the shape of a segment of a tubular sector, which is a cylinder rotated around the axis of rotation.

23. The sensor system according to any one of claims 13 to 17, characterized in that The magnetized body (10) has the shape of a segment of an angular sector of a disk, said shape being a cylinder of revolution about the axis of rotation.

24. The sensor system according to any one of claims 13 to 17, characterized in that The magnetized body (10) has the shape of an angular sector of a cylinder rotated about the main axis (A').

25. The sensor system according to any one of claims 13 to 17, characterized in that The main axis (A') coincides with the rotation axis (A).

26. The sensor system according to any one of claims 13 to 17, characterized in that The measuring plane ((AP1, AS1), (AP2, AS2)) of one or more of the measuring units is parallel to the rotation axis (A).

27. A method of manufacturing a magnetized body for use in a system for determining the relative angular position of a first component (14) relative to a second component (16) about an axis of rotation (A), the method comprising: providing a body of magnetizable material having the shape of a curved angular sector and having an angular extent around a main axis (A'), said angular sector comprising several consecutive angular portions or a single angular portion around said main axis (A'); Characterized in that the method comprises, for at least a first angular portion of the magnetized body: a first network of parallel electric conductors is arranged near a first angular portion of the body of magnetizable material, said first network comprising several bundles of parallel electric conductors, said bundles having an orientation (X1) perpendicular to said main axis and parallel to a first directrix radius originating from said main axis (A') and included in the angular extent of the considered first angular portion of said magnetizable body, said bundles being laterally offset from each other along an offset direction perpendicular to the orientation of said bundles and perpendicular to said main axis (A'); The current flows in the plurality of bundles of electrical conductors, the direction of the current flow being defined in a fixed reference system relative to the magnetizable body, being the same in all conductors of the same bundle and being opposite in two adjacent bundles, thereby forming one or several output bundles and one or several input bundles, wherein the current flows in the output bundles along a first direction and the current flows in the input bundles along a second direction opposite to the first direction, the current flowing in the bundles being capable of generating a magnetizing magnetic field around the network and in the magnetizable material body suitable for magnetizing the magnetizable material body.

28. The manufacturing method according to claim 27, characterized in that: The first network of parallel electrical conductors extends facing a first portion of the body of magnetizable material, the first portion being a single portion covering the angular extent of the body of magnetizable material.

29. The manufacturing method according to claim 27 or 28, characterized in that: The first directrix radius is oriented along a bisector of an angular extent of the body of magnetizable material.

30. The manufacturing method according to claim 27 or 28, characterized in that: The first network of parallel electric conductors extends facing a first portion of the body of magnetizable material, wherein a second network of parallel electric conductors extends facing a second portion of the body of magnetizable material different from the first portion, the plurality of parallel electric conductors of the second network being oriented along a second orientation (D2) perpendicular to the main axis (A') and parallel to a second directrix radius originating from the main axis (A') and included in the angular extent of the second angular portion under consideration.

31. The manufacturing method according to claim 27 or 28, characterized in that: The plurality of bundles of electrical conductors are formed by segments of at least one winding of a wire, along which at least a conductor of an outgoing bundle, a connecting segment, a conductor of an incoming bundle, a further connecting segment and a further conductor of the outgoing bundle repeatedly follow one another.

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