Classifications

• • H—ELECTRICITY
  • H02—GENERATION; CONVERSION OR DISTRIBUTION OF ELECTRIC POWER
  • H02K—DYNAMO-ELECTRIC MACHINES
  • H02K29/00—Motors or generators having non-mechanical commutating devices, e.g. discharge tubes or semiconductor devices
  • H02K29/06—Motors or generators having non-mechanical commutating devices, e.g. discharge tubes or semiconductor devices with position sensing devices
  • H02K29/08—Motors or generators having non-mechanical commutating devices, e.g. discharge tubes or semiconductor devices with position sensing devices using magnetic effect devices, e.g. Hall-plates, magneto-resistors
• • H—ELECTRICITY
  • H02—GENERATION; CONVERSION OR DISTRIBUTION OF ELECTRIC POWER
  • H02K—DYNAMO-ELECTRIC MACHINES
  • H02K11/00—Structural association of dynamo-electric machines with electric components or with devices for shielding, monitoring or protection
  • H02K11/01—Structural association of dynamo-electric machines with electric components or with devices for shielding, monitoring or protection for shielding from electromagnetic fields, i.e. structural association with shields
  • H02K11/014—Shields associated with stationary parts, e.g. stator cores
  • H02K11/0141—Shields associated with casings, enclosures or brackets
• • H—ELECTRICITY
  • H02—GENERATION; CONVERSION OR DISTRIBUTION OF ELECTRIC POWER
  • H02K—DYNAMO-ELECTRIC MACHINES
  • H02K11/00—Structural association of dynamo-electric machines with electric components or with devices for shielding, monitoring or protection
  • H02K11/20—Structural association of dynamo-electric machines with electric components or with devices for shielding, monitoring or protection for measuring, monitoring, testing, protecting or switching
  • H02K11/21—Devices for sensing speed or position, or actuated thereby
  • H02K11/215—Magnetic effect devices, e.g. Hall-effect or magneto-resistive elements
• • H—ELECTRICITY
  • H02—GENERATION; CONVERSION OR DISTRIBUTION OF ELECTRIC POWER
  • H02K—DYNAMO-ELECTRIC MACHINES
  • H02K29/00—Motors or generators having non-mechanical commutating devices, e.g. discharge tubes or semiconductor devices
  • H02K29/06—Motors or generators having non-mechanical commutating devices, e.g. discharge tubes or semiconductor devices with position sensing devices
  • H02K29/12—Motors or generators having non-mechanical commutating devices, e.g. discharge tubes or semiconductor devices with position sensing devices using detecting coils using the machine windings as detecting coil
• • H—ELECTRICITY
  • H02—GENERATION; CONVERSION OR DISTRIBUTION OF ELECTRIC POWER
  • H02K—DYNAMO-ELECTRIC MACHINES
  • H02K11/00—Structural association of dynamo-electric machines with electric components or with devices for shielding, monitoring or protection
  • H02K11/02—Structural association of dynamo-electric machines with electric components or with devices for shielding, monitoring or protection for suppression of electromagnetic interference
  • H02K11/028—Suppressors associated with the rotor

Definitions

• Rotor comprising a magnetic rotor rotation parameter detector
• the present invention relates to an electric vehicle machine
• the present invention relates to a rotor comprising a magnetic encoder located at one end of a rotor shaft as well as to an electric machine comprising such a rotor.
• the electrical machine comprises a control unit which receives, from a vehicle engine control unit, an alternator setpoint and controls the electrical supply of a coil of the rotor as a function of the angular speed of the rotor.
• a magnetic detector of rotor rotation parameters such as the
• angular position of the rotor generally comprises a magnetic encoder movable in rotation with the rotor, and at least one magnetic field sensor, fixed and located on the support of the machine.
• the magnetic encoder produces a magnetic field which is detected by at least one field sensor
• the magnetic rotor rotation parameters detector transforms this magnetic field detection into a signal corresponding to rotation parameters, such as the angular position of the rotor.
• the magnetic encoder therefore makes it possible to transmit information from
• the magnetic encoder can be a permanent magnet or an electromagnet comprising a face having at least one South pole and at least one North pole opposite the magnetic field sensor which detects the orientation of the magnetic field in function of the south pole or the north pole and converts this orientation information into rotation position parameters.
• the magnetic encoder can also include several magnets or several electromagnets which allow each pass in front of a magnetic field sensor to detect a magnetic field to determine a parameter of rotation of the rotor.
• the rotor of an electric motor vehicle machine such as a
• alternator or alternator-starter comprises a rotor shaft.
• the rotor shaft is made of magnetic steel.
• the rotor further includes an electric coil mounted on the rotor shaft. When the coil is energized, it produces a magnetic field in the axis of the rotor.
• the magnetic encoder of the magnetic rotor rotation parameter detector at the end of the shaft, that is to say at one end of the rotor shaft.
• the magnetic encoder is located at one end of the rotor shaft close to the electronic control unit of the electric machine.
• part of the magnetic field of the rotor coil is not channeled by the magnetic circuit of the rotor but is axially guided by the rotor shaft and disturbs the magnetic field of the magnetic encoder carried by the shaft rotor.
• the detection sensor detects both a magnetic field produced by the magnetic encoder and that produced by the rotor coil.
• the magnetic field of the rotor coil can combine with the magnetic field of the encoder and modify its characteristics such as the level of induction and / or the spatial orientation of the magnetic field vectors.
• the accuracy of the rotor rotation parameters is then affected by the use of a measurement of a global magnetic field and not of the magnetic field produced by the encoder only.
• One solution is to move the magnetic encoder away from the end of the rotor shaft made of magnetic material so that the magnetic field of the rotor coil disturbs the magnetic encoder less.
• a pad made of non-magnetic material to fix the encoder in this case a magnet in the form of a crown or ring at the end of the rotor shaft, having a space between the rotor shaft and the encoder.
• the non-magnetic pad therefore crosses the center of the encoder and the magnetic sensor is located opposite the non-magnetic pad.
• such a magnetic disc directly guides the magnetic field of the rotor in the crown-shaped encoder and therefore changes its magnetic field.
• the magnetic disc picks up a more or less significant part of its useful flux, which can lower the level of reading induction at the level of the sensor.
• the invention therefore relates to a rotor of a rotary electrical machine comprising: a rotor shaft comprising an axis of rotation and a fixing portion having a radial end surface and a peripheral fixing surface extending from the surface of radial end, a magnetic encoder device for a magnetic detector of rotor rotation parameters, the magnetic encoder device being fixed to the fixing portion and comprising a support comprising a partition wall made of non-magnetic material, and a magnetic encoder fixed to the support , the partition wall of the support separating the magnetic encoder from the rotor shaft.
• the partition wall of the support has an external radial surface and a recess, the recess having a bottom and an internal peripheral surface surrounding the peripheral surface for fixing the rotor shaft.
• non-magnetic material is meant that the material is of the type
• such a fixing portion has the advantage of being a simple means of fixing the magnetic encoder device to the rotor shaft.
• the fact of mounting the support around the rotor shaft to form a fixing portion of the magnetic encoder device allows the support of the magnetic encoder device to have a larger volume than in the case of a rod and therefore better resistance to deformation by centrifugal force in the event of imbalance.
• the rotor shaft has a metallic material of the steel type having a hardness sufficient to enable the fixing portion with very little risk of it being deformed by centrifugal force or when mounting the magnetic encoder device.
• the support made of non-magnetic material includes a hollow which surrounds the fixing portion makes it possible to increase the rigidity of the magnetic encoder device and therefore to better resist deformation by centrifugal force.
• the rotor of the invention makes it possible to improve, in a simple and
• the rotor according to the invention may also have one or more of the characteristics below, considered individually or in all technically possible combinations.
• the rotor shaft includes a shoulder having a radial surface, the peripheral fixing surface extending from the radial surface of the shoulder to the radial end surface.
• Shoulder means that the diameter of the peripheral fixing surface is smaller than the external diameter of the shaft before the shoulder.
• the shoulder reduces the radial size of the rotor.
• the magnetic encoder device further comprises a magnetic field shield formed of a magnetic material and being disposed between a portion of the support and the rotor shaft.
• the shield allows to deflect outward, field lines
• deflecting outwards we mean deflecting at least part of the magnetic field away from the axis of rotation.
• the shield comprises a radial wall located between the partition wall of the support and the radial surface of the shoulder, and an opening having an internal peripheral surface in contact with the peripheral surface for fixing the shaft. rotor.
• the non-magnetic support with the shield allows to deflect, radially outward, the axial magnetic field passing through the rotor shaft, to prevent the latter from disturbing the magnetic field of the magnetic detector.
• the fact that the shield is in contact with the fixing portion of the shaft makes it possible to deflect lines of magnetic fields passing through this portion towards the outside.
• a maximum external radius of the encoder of the magnetic encoder is less than a maximum external radius of the shield of the shield.
• the maximum shield radius greater than the maximum encoder radius causes the shield to extend radially beyond the encoder. This reduces or eliminates the fact that the axial magnetic field from the rotor coil passes through the encoder and thus improves the efficiency of the encoder.
• the magnetic encoder device is
• the opening or the recess includes a thread
• the magnetic encoder device comprises a tapping and the fixing portion is screwed into the tapping of the magnetic encoder device.
• the thread can be in the hollow of the support or the opening of the shield. This allows easy assembly and disassembly in the event of a fault with the magnetic encoder device.
• the shield comprises an enclosure
• peripheral extending axially from the radial wall, the peripheral enclosure being arranged between the peripheral surface of the hollow of the partition wall and the peripheral fixing surface.
• fixing portion to improve the deflection effect of the magnetic field lines coming from the rotor coil passing through the fixing portion using this portion for fixing the support of the magnetic encoder device.
• the internal peripheral surface of the hollow and the enclosure is configured to provide the internal peripheral surface of the hollow and the enclosure
• the device of the opening can be for example tubular and the fixing portion can have a cylindrical shape.
• the internal peripheral surface of the hollow of the partition wall is in contact with the peripheral fixing surface. This allows for a simpler form of the shield.
• the magnetic shield is made of steel
• the non-magnetic material of the support is
• diamagnetic such as plastic or paramagnetic such as de
• the shield comprises a protective bottom, said bottom being located between the bottom of the recess and the radial end surface of the shaft.
• the opening of the shield is sandwiched between the bottom of the recess and the radial end surface of the shaft. This ensures direct contact between the bottom of the shield opening and the radial portion.
• the bottom of the hollow of the partition wall is opposite the radial end surface of the fixing portion. This allows for a simpler form of the shield.
• the bottom of the hollow of the partition wall is in abutment against the radial end surface of the fixing portion.
• the shield is sandwiched between the external radial surface of the non-magnetic support and the radial surface of the shoulder. This makes it possible to have contact with the radial surface of the shoulder to guide the lines of magnetic fields.
• the rotor includes a clearance between the radial end surface of the shoulder and the bottom of the recess.
• the distance between the magnetic encoder and the radial shoulder surface is increased, making it possible to reduce the field lines passing through the encoder.
• the support comprises a retaining wall extending from the partition wall and surrounding the encoder, the partition wall and the retaining wall forming a housing in which is located the encoder.
• the retaining wall retains the magnet against centrifugal force.
• the encoder is glued or
• the shield comprises a protective wall extending around the retaining wall. This protects the encoder by axially guiding the field lines outside the housing.
• the protective wall and the shield radial wall are formed by two separate parts. This allows you to simply make the shield.
• the shield is in one piece. This simplifies assembly.
• the maximum radius of the shield is greater than a maximum outside radius of the radial surface of the shoulder.
• the rotor comprises a manifold comprising a fixing body made of electrical insulating material fixed on the rotor shaft.
• the shield further comprises a surface in contact with the fixing body of the collector. This allows the collector to be used to protect the shield against pathogens, for example against water including iodine which can cause corrosion of the shield.
• the fixing portion of the shaft comprises an axial hole opening out on the radial end surface.
• the hole guides the lines of the magnetic field in the axis towards the outside of the radial end surface and towards the peripheral fixing surface.
• the hole includes a surface that widens from the peripheral inner surface to the radial end surface. This flared shape improves the guidance of the magnetic field to the part of the radial end surface farthest from the axis of rotation.
• the shield is molded with the support.
• the encoder is a magnet comprising a free face having a south polarization and a north polarization, the free face being the free end of the encoding device.
• the encoder comprises a
• the encoder is a track made of magnetic material making it possible to guide a magnetic field coming from the magnetic detector towards the sensor.
• the encoder is an electromagnet.
• the invention also relates to an electric machine comprising a rotor according to the invention or comprising one or more combined characteristics of the various embodiments described, a machine support supporting the rotor, a magnetic detector for rotor rotation parameters comprising the encoder device and in addition at least one magnetic field sensor facing the encoder for sensing the magnetic field of the encoder.
• the magnetic field sensor is fixed to the machine support.
• the magnetic field sensor is a hall effect sensor or a magneto-resistive sensor.
• the magnetic detector for rotor rotation parameters comprises three magnetic field sensors.
• the machine comprises an alternator mode for a motor vehicle comprising an electric machine as described above.
• the magnetic field shield is formed integrally with the tree.
• the invention also relates to an alternator-starter for a motor vehicle comprising an electric machine as described above further comprising an engine mode for starting the engine or relieving the torque of the engine.
• the invention also relates to a reversible machine or an electric motor for a motor vehicle comprising an electric machine as described above capable, in addition to supplying torque to the heat engine.
• FIG. 1a shows a block diagram of an axial section of a half of an electric machine comprising a rotor according to a first example of a first embodiment.
• FIG. 1b shows part of a rear portion of a rotor shaft of the rotor according to the first example of the first embodiment.
• Figure 1 c shows a block diagram of an axial section of a portion of a rear portion of a rotor of Figure 1 a.
• FIG. 2 shows a block diagram of an axial section of a portion of the rear portion of a rotor according to a second example of the first embodiment.
• FIG. 3a] and [ Figure 3b] each represent a front view of a shield of a rotor according to different examples of the first embodiment.
• FIG. 4 shows a block diagram of an axial section of a portion of the rear portion of a rotor according to a first example of a second embodiment.
• FIG. 5 shows a block diagram of an axial section of a portion of the rear portion of a rotor according to a second example of a second embodiment.
• FIG. 6 shows a block diagram of an axial section of a portion of the rear portion of a rotor according to a first example of a third embodiment.
• Figure 7 shows a block diagram of an axial section of a portion of the rear portion of a rotor according to a first example of a fourth embodiment.
• FIG. 8 shows a block diagram of an axial section of a portion of the rear portion of a rotor according to a fifth embodiment.
• FIG. 1a shows a block diagram of an axial section of one half of an electric machine M comprising a rotor A according to a first example of a first embodiment.
• the electric machine M in particular a rotary electric machine, can be an alternator or an alternator-starter or a reversible machine or an electric motor for a motor vehicle.
• the electric machine M comprises a machine support S supporting a stator comprising a sheet metal package T and a coil B wound in the sheet metal package T.
• the electric machine M also comprises a front bearing Pa and a rear bearing Pr, in this case ball bearings, each fitted into the machine support S.
• the rotor A comprises a rotor shaft 1 comprising an axis of rotation X.
• the rotor shaft 1 includes an outer periphery, in this case in the form of a cylinder.
• the rotor shaft 1 comprises two support portions comprising a part of the external periphery.
• Each support portion is located in the front bearing Pa and the rear bearing Pr to make the rotor A free to rotate relative to the machine support S.
• the front bearing Pa and the rear bearing Pr allow the machine support S to support the rotor A.
• these two support portions are each mounted in an inner ring of the corresponding bearing.
• the rotor shaft 1 further comprises a front radial end surface 11 'and a rear radial end surface 11, a central portion between the support portion of the front bearing Pa and the support portion of the rear bearing Pr, a front portion between its front radial end face and the front bearing and a rear portion between its rear end surface 11 and the rear bearing Pr.
• the radial end surface is a surface extending in one direction radial and being located at an axial end of the rotor shaft.
• the rotor A is in this case a claw rotor, but could be another type of rotor.
• the rotor A therefore comprises two claw bodies AG of magnetic material, in this case ferromagnetic alloy, mounted tightly on the external periphery of the central portion of the rotor shaft 1.
• the rotor A further comprises a coil AB wound between the two claw bodies AG.
• the rotor A comprises a collector 2 surrounding a part of the rear portion of the rotor shaft 1.
• the collector 2 comprises a fixing body 20, made of insulating material.
• the fixing body 20 is fixed on the outer periphery of the rotor shaft 1, in this case the outer periphery of the rear portion of the rotor shaft 1.
• the collector 2 further comprises electrical tracks, in this case in this example two copper rings, mounted on the fixing body 20. These tracks are electrically connected to the coil AB to power it.
• the electric machine further comprises a brush holder S2 comprising brushes, in this case two brushes, each brush being in contact with one of the tracks to supply the coil AB.
• FIG. 1b shows a part of the rear portion of the rotor shaft 1 of the rotor A with a portion of the fixing body 20 of the manifold 2.
• the rotor shaft 1 further comprises on its rear portion, a shoulder 12 comprising a radial surface 120.
• the rear portion comprises a fixing portion 13 extending from the shoulder to the radial end surface 11.
• the fixing portion 13 comprises a peripheral fixing surface 130 s' extending from the radial surface 120 of the shoulder to the radial end surface 11.
• the electric machine M further comprises a magnetic detector of
• rotor rotation parameters D surrounded in [ Figure 1 a] by a dotted rectangle, comprising a magnetic encoder device 3 mounted on the rotor shaft 1 and a magnetic position sensor 5 mounted on the machine support S.
• the machine electric M further comprises an electronic control unit U fixed to the machine support S.
• the electronic control unit U is connected to the magnetic position sensor 5 to receive signals according to the rotation of the magnetic encoder device 3.
• the unit electronic control unit U therefore comprises a means for calculating rotation parameters, thus making it possible to calculate rotation parameters, such as the position, the speed and the direction of rotation of the rotor A with respect to the machine support S.
• the rotor A therefore comprises, in a part of its rear portion, the magnetic encoder device 3 fixed to the fixing portion 13 of the rear portion of the rotor shaft 1.
• FIG. 1 c shows the part of the rear portion of the rotor comprising the magnetic encoder device 3.
• the encoder device 3 comprises a support 32 comprising a partition wall 321, made of non-magnetic material, for example plastic.
• the support 32 is in one piece and is made of plastic.
• the partition wall 321 includes a radial surface external 3210 and a recess, the recess having an internal peripheral surface 3213 surrounding the peripheral fixing surface 130 and a bottom 3211.
• the magnetic encoder device 3 further comprises a magnetic field shield 31, made of magnetic material, for example steel
• the shield 31 comprises a radial wall 310 situated between the partition wall 321 of the support and the radial surface 120 of the shoulder 12.
• the shield 31 comprises an opening comprising an internal peripheral surface 313 in contact with the peripheral fixing surface 130 of rotor shaft 1.
• Figure 1 shows, in addition according to a block diagram, magnetic field lines H1, H2, H3 from the coil AB passing through the rotor shaft 1 and the machine support S.
• the coil produces an infinity of field lines passing through the rotor shaft.
• the coil AB produces other types of magnetic field lines, for example between the claw bodies AG and the package of stator plates T which are not shown.
• the rotor shaft 1 made of magnetic material and leave on either side of the rotor shaft 1 by means of these two faces of radial ends 11 and 11 ’.
• the magnetic field lines are closer to each other than those on the side of the radial end face 11 ’.
• the shield 31 therefore makes it possible to guide the magnetic field lines exiting from the rear radial end face 11 towards the outside, that is to say radially towards the machine support S.
• the shield 31 allows limit the magnetic field through the encoder 33.
• the magnetic field sensor 5 can therefore measure a magnetic field produced by the encoder 33 more precisely. This improves the reliability of the encoder 33.
• Figure 3a shows the shield 31 seen from the front.
• the shield 31 is mounted tightly on the fixing portion 13, for example by fitting.
• the shield 31 ’secured to the fixing portion 13 is shown seen from the front before plastic deformation of the magnetic material of the shield 31’.
• the shield 31 ’ is fixed to the rotor shaft 1 by being mounted tight on the fixing portion 13 by deformation of material at its opening.
• the shield 31 includes, in the opening, triangular teeth. The top of each tooth has a smaller radius than the radius of the fixing portion 13 and the bottom, between two teeth, has a larger diameter than that of the fixing portion 13.
• the teeth are plastically deformed allowing a tight mounting and therefore in particular a good contact between the shield 31 'and the fixing portion 13.
• the magnetic encoder device 3 further comprises an encoder
• the partition wall 321 is located between the encoder 33 and the rotor shaft 1.
• the support 32 may include a retaining wall 322 surrounding the encoder 33.
• the partition wall 321 and the retaining wall 322 form a housing in which the encoder is located.
• the encoder 33 is, in this case, a magnet of which only the northern part is shown in [Figure 1a] since it represents only half of the rotor A.
• the encoder 33 therefore comprises a face radial comprising the north pole and the south pole visible in [ Figure 1 c].
• only the north pole is opposite the magnetic sensor 5, but if the rotor A rotates by half a turn, the south pole would be in front of the magnetic sensor 5.
• the electric machine M may include several magnetic sensors 5 facing the radial face of the encoder 33 to have better precision of the angular position of the rotor A.
• the encoder 33 could also be a track comprising several magnets distributed angularly or include coils and a core of material ferromagnetic. The encoder 33 is therefore the active magnetic part of the encoder device 3.
• the encoder 33 has a maximum radius, called the maximum encoder radius R33, relative to the axis of rotation X.
• the maximum encoder radius R33 is therefore the largest radius of the encoder 33.
• the shield 31 includes a maximum radius, called in the following radius
• maximum shield R31 larger than the maximum encoder radius R33.
• the maximum shield radius R31 is also greater than the radius of the rear part of the shaft 1.
• the opening of the shield 31 is open and the bottom 321 1 of the hollow is opposite the radial end surface 11 of the fixing portion 13.
• the fixing portion 13 passes through the opening of the shield 31 and the hollow of the support 32.
• the rotor comprises a clearance between the surface of radial end 11 of the fixing portion 13 and the bottom 3211 and on the other hand the radial wall 310 is sandwiched between the radial surface 120 of the shoulder 12 and the external radial surface 3210 of the support 32.
• the rotor is identical to the first example except that the bottom 3211 of the hollow of the support 32 is in contact with the radial end surface 11 of the shaft 1.
• the magnetic encoder device 3 is different from the previous example in that a clearance is formed between the shield 31 and the partition wall 321 of the support 32. This makes it possible to have contact between the radial surface of the shoulder and the shield.
• the support 32 is made of non-magnetic steel, for example aluminum, and comes from a folded and perforated plate to form the hollow.
• the external radial surface 3210 of the partition wall 321 is in contact with the radial wall 310 of the shield and a clearance is formed between the radial surface 120 of the shoulder 12 and the radial wall 310 of the shield 31. This makes it possible to be able to mount the magnetic encoder device 3 on the rotor shaft 1 in a single step.
• the shield 31 has the shape of a washer, in
• flat washer a washer comprising an opening opening axially and formed of the radial wall 310 between its internal radius corresponding to the opening and its external radius.
• the maximum shield radius R31 therefore corresponds here to the external radius.
• the shield 31 B comprises a protective wall 312 surrounding the retaining wall 322.
• the retaining wall 322 and the protective wall 312 are tubular.
• the shield 31 B is formed in two parts, on the one hand the radial wall 310 in the form of a washer identical to that of the first embodiment and on the other hand the protective wall 312.
• the radial wall 310 and the protective wall 312 are two separate parts and the rotor includes a clearance between these two walls.
• the radial wall 310 in this example is in contact with the radial surface 120 of the shoulder 12 of the rotor shaft 1.
• the radial wall 310 is in contact with the wall of protection 312 or in contact with the partition wall 321.
• the protective wall 312 can be forcibly mounted on the support 32, in particular on the retaining wall 322 or molded by the support 32 in the case where the support is made of plastic.
• the protective wall 312 further surrounds the partition wall 321 but could only surround the retaining wall 322. In this case the protective wall 312 extends beyond the partition wall 321.
• FIG. 5 A second example of this second embodiment is shown in [ Figure 5]
• the shield 31 B ’ is in one piece, so the two walls are made of material.
• the shield 31 B ′ therefore has a radial wall 310 and a protective wall 312 which extends from the radial wall 310, in this case the outer end of the radial wall 310.
• the side wall 310 of the shield 31 B ’ is in contact with the radial surface 120 of the shoulder.
• the shield 31 C further comprises a peripheral enclosure 311 extending from the radial wall 310.
• the peripheral enclosure 311 allows the shield 31 to be fixed around the fixing portion 13.
• the peripheral enclosure 31 1 and the radial wall 310 are in one piece.
• the peripheral surface 313 of the opening of the shield 31 therefore extends in the radial wall 310 and in the peripheral enclosure 311.
• the shield 31 C comes from a ferromagnetic plate perforated and folded to form the opening and the peripheral enclosure 311.
• peripheral 31 1 is sandwiched between the internal peripheral surface 3213 of the hollow of the partition wall 321 and the peripheral fixing surface 130 of the fixing portion 13.
• the peripheral fixing surface 130, the internal peripheral surface 3213 of the hollow of the partition wall 321 and the peripheral enclosure 31 1 are cylindrical.
• the peripheral surface of the hollow of the support 32 is no longer in contact with the shaft 1.
• the bottom 321 1 of the hollow is in contact with the radial end surface 1 1 and there is a clearance between the shield 31 C and the radial surface 120 of the shoulder 12.
• the clearance is between the bottom 321 1 of the hollow and the radial end surface 1 1.
• the shield 31 C can be molded by the support 32.
• a fourth embodiment of the rotor will now be described. It is identical to the third embodiment except as regards the shield 31 D.
• the shield 31 D has a protective wall 312 as in the second example of the second embodiment.
• the shield 31 D therefore comprises a peripheral enclosure 31 1 fixed around the fixing portion 13 as in the third embodiment.
• the bottom 321 1 of the hollow is in contact with the radial end surface 1 1 but according to another implementation, there could be a clearance between the radial end surface 1 1 and the bottom 321 1 of the hollow.
• the shield comes from a magnetic metal plate such as steel comprising iron and is perforated and folded to form the protective wall 312, the side wall 310 and the peripheral enclosure 31 1.
• a fifth embodiment of the rotor will now be described. It is identical to the fourth embodiment except with regard to the shield 31 E.
• the opening of the shield 31 E includes a protective bottom 31 11 unlike the embodiments in which the opening is open.
• the shield 31 E therefore comprises in this example a protective wall 312 surrounding the retaining wall 322 and the partition wall 321 of the support 32, a radial wall 310 between the partition wall and the radial surface 120 of the shoulder 12, a peripheral enclosure 31 1 fixed on the peripheral fixing surface 130 and a protective base 3111 extending of the peripheral enclosure 311.
• the shield 31 E is identical to that of the third example except in that it comprises a protective bottom 3111 and is devoid of the protective portion 312 .
• the fixing portion 13 comprises an axial hole 134 opening onto the radial end surface 11.
• the hole 134 comprises a bottom, in this case cone-shaped, a cylindrical surface extending along the axis X and a flaring surface from the cylindrical surface towards the radial end surface 11, in this case a conical surface whose largest radius opens onto the radial end surface 11.
• the protective bottom 31 11 of the shield 1 1 therefore plugs the hole 134.
• the hole 134 makes it possible to guide the waves towards the enclosure 311 of the shield 31 E.
• the fixing portion 13 is devoid of the hole 134.
• the fixing portion 13 comprises a hole 134 opening axially on the radial end surface 11.
• the hole 134 may include the surface flaring from the axis towards the radial end surface 1 1.
• the magnetic field coming from the coil AB of the rotor A passing through the fixing portion 13 of the rotor shaft 1 is guided towards the outside of the rotor by passing through the side wall 310 of the shield 31.
• the assembly of the fixing portion 13 with the support 32 can be done according to several alternatives, whatever the embodiment described above.
• the internal peripheral surface 3213 of the recess in the partition wall 321 has teeth extending axially.
• the support 32 is for example molded from plastic. These teeth allow the support 32 to be fixed on the smooth peripheral surface 130 of the fixing portion.
• the teeth are distributed equidistantly on the internal peripheral surface of the hollow 3213 in order to ensure optimal centering between the support 32 and the rotor shaft 1.
• teeth can be hollowed out in order to control the fitting force and the deformation of the material, as well as to guarantee a constant thickness of molding. This morphology of teeth allows their deformation during
• a non-magnetic insert can also be provided at the internal peripheral surface 3213 of the hollow.
• a non-magnetic metallic insert is for example composed of aluminum or stainless steel 304 or 316L in a plastic support 32. Such a solution improves the holding
• the assembly of the fixing portion 13 to the support 32 can be made by shrinking to ensure a level of clamping between the fixing portion 13 and the support 32 sufficient for a robust mechanical resistance to vibrations and rotation of the device.
• Such a solution makes it possible to reduce the cost of the part, and makes it possible to ensure assembly without the risk of damaging the support 32 and to simplify the structure of the shaft 1.
• the peripheral surface of the fixing portion 130 and the surface internal periphery of the hollow 3213 are smooth.
• the rise in temperature of the support 32 makes it possible to temporarily increase the internal diameter of the hollow, for assembly with the fixing portion 13. Then the return to ambient temperature of the support 32 In such an embodiment, the temperature is controlled so as not to generate a
• the support 32 is a plastic molded part which incorporates a fixing system composed of two cylindrical clips positioned at 180 ° relative to each other and snapping into a groove machined on the surface peripheral of the fixing portion 13, without knurling, the support 32 also includes an anti-rotation device consisting of two tongues, angularly offset by 90 ° relative to the clips and fitting into the grooves of the fixing portion 13, and a centering mechanism comprising a 4mm ball pressed into the frustoconical housing formed at the end of the fixing portion 13 by a cylindrical compression spring.
• This assembly generates at the same time a prestress aimed at exerting traction of the clip heads against the internal peripheral surface of the hollow 3213.
• the ball can be replaced by a centering pin, of generally cylindrical shape with a conical end, which is positioned in the central through hole of the shaft end, during assembly of the encoder .
• An elastic washer can also replace the compression spring.
• the encoder can be held in the support 32 either by gluing or by overmolding a closure wall covering its upper face opposite the Hall effect sensor.
• opening diametrically is practiced in the shaft in an axis
• a pin is fitted into the bore described above to ensure stops in translation and in rotation.
• the pin can be a cylindrical pin with or without a tapped hole to facilitate its extraction, a grooved pin.
• the pin can be replaced by a cylindrical key or a round transverse key (tangential).
• the outside diameter of the pin is approximately three times smaller than that of the drive shaft.
• the magnet shape thus obtained makes it possible to reference the direction of easy magnetization of the magnet in order to ensure optimal magnetization of the magnet.
• the shaft may not have a shoulder and the shield and support may be mounted directly on the outer diameter of the shaft.

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• Transmission And Conversion Of Sensor Element Output (AREA)
• Motor Or Generator Frames (AREA)

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• 2018
  • 2018-12-11 FR FR1872723A patent/FR3089714B1/fr active Active
• 2019
  • 2019-12-11 CN CN201980081502.2A patent/CN113243074A/zh active Pending
  • 2019-12-11 WO PCT/EP2019/084637 patent/WO2020120572A1/fr unknown
  • 2019-12-11 EP EP19816350.3A patent/EP3895290A1/de not_active Withdrawn

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