Classifications

• • B—PERFORMING OPERATIONS; TRANSPORTING
  • B64—AIRCRAFT; AVIATION; COSMONAUTICS
  • B64C—AEROPLANES; HELICOPTERS
  • B64C25/00—Alighting gear
  • B64C25/32—Alighting gear characterised by elements which contact the ground or similar surface 
  • B64C25/42—Arrangement or adaptation of brakes
• • H—ELECTRICITY
  • H02—GENERATION; CONVERSION OR DISTRIBUTION OF ELECTRIC POWER
  • H02K—DYNAMO-ELECTRIC MACHINES
  • H02K49/00—Dynamo-electric clutches; Dynamo-electric brakes
  • H02K49/02—Dynamo-electric clutches; Dynamo-electric brakes of the asynchronous induction type
  • H02K49/04—Dynamo-electric clutches; Dynamo-electric brakes of the asynchronous induction type of the eddy-current hysteresis type
  • H02K49/046—Dynamo-electric clutches; Dynamo-electric brakes of the asynchronous induction type of the eddy-current hysteresis type with an axial airgap
• • B—PERFORMING OPERATIONS; TRANSPORTING
  • B60—VEHICLES IN GENERAL
  • B60L—PROPULSION OF ELECTRICALLY-PROPELLED VEHICLES; SUPPLYING ELECTRIC POWER FOR AUXILIARY EQUIPMENT OF ELECTRICALLY-PROPELLED VEHICLES; ELECTRODYNAMIC BRAKE SYSTEMS FOR VEHICLES IN GENERAL; MAGNETIC SUSPENSION OR LEVITATION FOR VEHICLES; MONITORING OPERATING VARIABLES OF ELECTRICALLY-PROPELLED VEHICLES; ELECTRIC SAFETY DEVICES FOR ELECTRICALLY-PROPELLED VEHICLES
  • B60L15/00—Methods, circuits, or devices for controlling the traction-motor speed of electrically-propelled vehicles
  • B60L15/20—Methods, circuits, or devices for controlling the traction-motor speed of electrically-propelled vehicles for control of the vehicle or its driving motor to achieve a desired performance, e.g. speed, torque, programmed variation of speed
  • B60L15/2009—Methods, circuits, or devices for controlling the traction-motor speed of electrically-propelled vehicles for control of the vehicle or its driving motor to achieve a desired performance, e.g. speed, torque, programmed variation of speed for braking
• • B—PERFORMING OPERATIONS; TRANSPORTING
  • B60—VEHICLES IN GENERAL
  • B60L—PROPULSION OF ELECTRICALLY-PROPELLED VEHICLES; SUPPLYING ELECTRIC POWER FOR AUXILIARY EQUIPMENT OF ELECTRICALLY-PROPELLED VEHICLES; ELECTRODYNAMIC BRAKE SYSTEMS FOR VEHICLES IN GENERAL; MAGNETIC SUSPENSION OR LEVITATION FOR VEHICLES; MONITORING OPERATING VARIABLES OF ELECTRICALLY-PROPELLED VEHICLES; ELECTRIC SAFETY DEVICES FOR ELECTRICALLY-PROPELLED VEHICLES
  • B60L7/00—Electrodynamic brake systems for vehicles in general
  • B60L7/24—Electrodynamic brake systems for vehicles in general with additional mechanical or electromagnetic braking
• • B—PERFORMING OPERATIONS; TRANSPORTING
  • B60—VEHICLES IN GENERAL
  • B60L—PROPULSION OF ELECTRICALLY-PROPELLED VEHICLES; SUPPLYING ELECTRIC POWER FOR AUXILIARY EQUIPMENT OF ELECTRICALLY-PROPELLED VEHICLES; ELECTRODYNAMIC BRAKE SYSTEMS FOR VEHICLES IN GENERAL; MAGNETIC SUSPENSION OR LEVITATION FOR VEHICLES; MONITORING OPERATING VARIABLES OF ELECTRICALLY-PROPELLED VEHICLES; ELECTRIC SAFETY DEVICES FOR ELECTRICALLY-PROPELLED VEHICLES
  • B60L7/00—Electrodynamic brake systems for vehicles in general
  • B60L7/28—Eddy-current braking
• • B—PERFORMING OPERATIONS; TRANSPORTING
  • B60—VEHICLES IN GENERAL
  • B60T—VEHICLE BRAKE CONTROL SYSTEMS OR PARTS THEREOF; BRAKE CONTROL SYSTEMS OR PARTS THEREOF, IN GENERAL; ARRANGEMENT OF BRAKING ELEMENTS ON VEHICLES IN GENERAL; PORTABLE DEVICES FOR PREVENTING UNWANTED MOVEMENT OF VEHICLES; VEHICLE MODIFICATIONS TO FACILITATE COOLING OF BRAKES
  • B60T13/00—Transmitting braking action from initiating means to ultimate brake actuator with power assistance or drive; Brake systems incorporating such transmitting means, e.g. air-pressure brake systems
  • B60T13/74—Transmitting braking action from initiating means to ultimate brake actuator with power assistance or drive; Brake systems incorporating such transmitting means, e.g. air-pressure brake systems with electrical assistance or drive
  • B60T13/746—Transmitting braking action from initiating means to ultimate brake actuator with power assistance or drive; Brake systems incorporating such transmitting means, e.g. air-pressure brake systems with electrical assistance or drive and mechanical transmission of the braking action
• • B—PERFORMING OPERATIONS; TRANSPORTING
  • B60—VEHICLES IN GENERAL
  • B60T—VEHICLE BRAKE CONTROL SYSTEMS OR PARTS THEREOF; BRAKE CONTROL SYSTEMS OR PARTS THEREOF, IN GENERAL; ARRANGEMENT OF BRAKING ELEMENTS ON VEHICLES IN GENERAL; PORTABLE DEVICES FOR PREVENTING UNWANTED MOVEMENT OF VEHICLES; VEHICLE MODIFICATIONS TO FACILITATE COOLING OF BRAKES
  • B60T13/00—Transmitting braking action from initiating means to ultimate brake actuator with power assistance or drive; Brake systems incorporating such transmitting means, e.g. air-pressure brake systems
  • B60T13/74—Transmitting braking action from initiating means to ultimate brake actuator with power assistance or drive; Brake systems incorporating such transmitting means, e.g. air-pressure brake systems with electrical assistance or drive
  • B60T13/748—Transmitting braking action from initiating means to ultimate brake actuator with power assistance or drive; Brake systems incorporating such transmitting means, e.g. air-pressure brake systems with electrical assistance or drive acting on electro-magnetic brakes
• • B—PERFORMING OPERATIONS; TRANSPORTING
  • B64—AIRCRAFT; AVIATION; COSMONAUTICS
  • B64C—AEROPLANES; HELICOPTERS
  • B64C25/00—Alighting gear
  • B64C25/32—Alighting gear characterised by elements which contact the ground or similar surface 
  • B64C25/42—Arrangement or adaptation of brakes
  • B64C25/44—Actuating mechanisms
• • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
  • F16—ENGINEERING ELEMENTS AND UNITS; GENERAL MEASURES FOR PRODUCING AND MAINTAINING EFFECTIVE FUNCTIONING OF MACHINES OR INSTALLATIONS; THERMAL INSULATION IN GENERAL
  • F16D—COUPLINGS FOR TRANSMITTING ROTATION; CLUTCHES; BRAKES
  • F16D55/00—Brakes with substantially-radial braking surfaces pressed together in axial direction, e.g. disc brakes
  • F16D55/24—Brakes with substantially-radial braking surfaces pressed together in axial direction, e.g. disc brakes with a plurality of axially-movable discs, lamellae, or pads, pressed from one side towards an axially-located member
  • F16D55/26—Brakes with substantially-radial braking surfaces pressed together in axial direction, e.g. disc brakes with a plurality of axially-movable discs, lamellae, or pads, pressed from one side towards an axially-located member without self-tightening action
  • F16D55/36—Brakes with a plurality of rotating discs all lying side by side
  • F16D55/38—Brakes with a plurality of rotating discs all lying side by side mechanically actuated
• • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
  • F16—ENGINEERING ELEMENTS AND UNITS; GENERAL MEASURES FOR PRODUCING AND MAINTAINING EFFECTIVE FUNCTIONING OF MACHINES OR INSTALLATIONS; THERMAL INSULATION IN GENERAL
  • F16D—COUPLINGS FOR TRANSMITTING ROTATION; CLUTCHES; BRAKES
  • F16D65/00—Parts or details
  • F16D65/14—Actuating mechanisms for brakes; Means for initiating operation at a predetermined position
  • F16D65/16—Actuating mechanisms for brakes; Means for initiating operation at a predetermined position arranged in or on the brake
  • F16D65/18—Actuating mechanisms for brakes; Means for initiating operation at a predetermined position arranged in or on the brake adapted for drawing members together, e.g. for disc brakes
  • F16D65/186—Actuating mechanisms for brakes; Means for initiating operation at a predetermined position arranged in or on the brake adapted for drawing members together, e.g. for disc brakes with full-face force-applying member, e.g. annular
• • H—ELECTRICITY
  • H02—GENERATION; CONVERSION OR DISTRIBUTION OF ELECTRIC POWER
  • H02K—DYNAMO-ELECTRIC MACHINES
  • H02K49/00—Dynamo-electric clutches; Dynamo-electric brakes
  • H02K49/02—Dynamo-electric clutches; Dynamo-electric brakes of the asynchronous induction type
  • H02K49/04—Dynamo-electric clutches; Dynamo-electric brakes of the asynchronous induction type of the eddy-current hysteresis type
• • B—PERFORMING OPERATIONS; TRANSPORTING
  • B60—VEHICLES IN GENERAL
  • B60L—PROPULSION OF ELECTRICALLY-PROPELLED VEHICLES; SUPPLYING ELECTRIC POWER FOR AUXILIARY EQUIPMENT OF ELECTRICALLY-PROPELLED VEHICLES; ELECTRODYNAMIC BRAKE SYSTEMS FOR VEHICLES IN GENERAL; MAGNETIC SUSPENSION OR LEVITATION FOR VEHICLES; MONITORING OPERATING VARIABLES OF ELECTRICALLY-PROPELLED VEHICLES; ELECTRIC SAFETY DEVICES FOR ELECTRICALLY-PROPELLED VEHICLES
  • B60L2200/00—Type of vehicles
  • B60L2200/10—Air crafts
• • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
  • F16—ENGINEERING ELEMENTS AND UNITS; GENERAL MEASURES FOR PRODUCING AND MAINTAINING EFFECTIVE FUNCTIONING OF MACHINES OR INSTALLATIONS; THERMAL INSULATION IN GENERAL
  • F16D—COUPLINGS FOR TRANSMITTING ROTATION; CLUTCHES; BRAKES
  • F16D2121/00—Type of actuator operation force
  • F16D2121/18—Electric or magnetic
  • F16D2121/20—Electric or magnetic using electromagnets
• • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
  • F16—ENGINEERING ELEMENTS AND UNITS; GENERAL MEASURES FOR PRODUCING AND MAINTAINING EFFECTIVE FUNCTIONING OF MACHINES OR INSTALLATIONS; THERMAL INSULATION IN GENERAL
  • F16D—COUPLINGS FOR TRANSMITTING ROTATION; CLUTCHES; BRAKES
  • F16D2200/00—Materials; Production methods therefor
  • F16D2200/0004—Materials; Production methods therefor metallic
  • F16D2200/0008—Ferro
  • F16D2200/0013—Cast iron
• • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
  • F16—ENGINEERING ELEMENTS AND UNITS; GENERAL MEASURES FOR PRODUCING AND MAINTAINING EFFECTIVE FUNCTIONING OF MACHINES OR INSTALLATIONS; THERMAL INSULATION IN GENERAL
  • F16D—COUPLINGS FOR TRANSMITTING ROTATION; CLUTCHES; BRAKES
  • F16D2200/00—Materials; Production methods therefor
  • F16D2200/0004—Materials; Production methods therefor metallic
  • F16D2200/0008—Ferro
  • F16D2200/0021—Steel

Definitions

• the present invention relates to the field of braking vehicle wheels such as aircraft wheels.
• An aircraft wheel generally comprises a rim connected by a web to a hub mounted to rotate on a wheel support shaft (axle or knuckle).
• Friction braking devices comprising a stack of braking discs which is housed in a space extending between the rim and the hub and which comprises an alternation of rotor discs connected in rotation with the wheel and discs stators fixed in rotation relative to the wheel support.
• the braking device also comprises hydraulic or electromechanical actuators mounted on an actuator carrier and arranged to apply a controlled braking force to the stack of discs so as to slow the rotation of the wheel.
• eddy current magnetic braking devices used for braking vehicle wheels and more particularly aircraft wheels.
• Document WO-A-2014/029962 describes such a device comprising a rotor which is provided with one or more magnets and which is mounted facing an electromagnetic stator.
• Document US-A-20200300310 also describes an eddy current magnetic braking device. Furthermore, the magnetic braking torque by eddy current depends directly on the speed of the central element with respect to the external elements so that this torque is zero when the speed is zero. It is therefore necessary to provide additional braking means for low speeds and/or when the aircraft is stationary (parking brake). This supposes that the weight of the whole is increased.
• the object of the invention is in particular to propose an eddy current magnetic braking device remedying at least in part the aforementioned drawbacks.
• a landing gear comprising a leg having one end carrying a shaft on which is mounted the hub of a wheel provided with a positive eddy current magnetic braking device.
• the device comprises two external elements framing a central element aligned on the same axis with the external elements and in rotation around said axis with respect to the external elements, the external elements having first faces opposite second opposite faces of the central element and each carrying a plurality of magnets able to emit via the first faces a magnetic flux generating in the central element, made of electrically conductive material, eddy currents when the elements are in relative motion.
• the magnets being arranged in such a way as to generate a magnetic attraction between the external elements.
• First friction braking surfaces are rotatably linked to the outer members and second friction braking surfaces are rotatably linked to the central member and the outer members are movable with respect to the axis between a position close to the central element in which the first braking surfaces are held applied against the second braking surfaces by the magnetic attraction and a spaced position from the central element in which the first braking surfaces swim away from the second braking surfaces.
• This arrangement makes it possible to optimize braking by friction which is integrated into the magnetic brake and whose maintenance does not require a source of energy since it is the magnetic attraction of the magnets which will keep the braking surfaces in contact and in this way generate a tightening of the central element between the external elements.
• the braking torque depends on the power of the magnets, but if the friction braking is used only as a parking brake and possibly to slow the wheel at low speed, the attraction by the magnets will be sufficient for the parking brake .
• the invention also relates to a braked wheel equipped with such a device and a landing gear equipped with such a wheel.
• Figure 1 is a partial schematic view of an aircraft equipped with landing gear according to the invention
• FIG. 2 is a perspective view of a wheel according to the invention, the wheel being devoid of its tire;
• Figure 3 is a partial schematic view of this wheel, in section along the plane III of Figure 2, showing a magnetic braking device according to a first embodiment, this braking device being equipped with an actuator according to a first embodiment;
• Figure 4 is a partial schematic view of this wheel, in section along the plane IV of Figure 2;
• Figure 5 is a partial schematic view of this wheel, in section along the plane V of Figure 2;
• FIG. 6 is a perspective view of the driving crown and the pinions of the transmission assemblies according to a first variant of the first embodiment of the actuator;
• Figure 7 is a view similar to that of Figure 4 of the wheel according to this variant embodiment.
• Figure 8 is a view similar to that of Figure 5 of the wheel according to this variant embodiment;
• Figure 9 is a partial front view of the wheel showing the gears of the transmission assemblies according to a second variant of the first embodiment of the actuator;
• Figure 10 is a view similar to that of Figure 4 of the wheel, the magnetic braking device being equipped with an actuator according to a second embodiment;
• FIG. 11 is a view similar to that of FIG. 5 of the wheel, showing the actuator according to the second embodiment;
• FIG. 12 is a partial schematic view of a stator according to a first embodiment
• FIG. 13 is a partial schematic view of a stator according to a second embodiment
• FIG. 14 is a partial schematic view of a stator according to a third embodiment
• FIG. 15 is a partial schematic view of a stator of the magnetic braking device according to the first embodiment
• FIG. 16 is a view similar to that of FIG. 3, showing a magnetic braking device according to a second embodiment.
• each landing gear 101 comprises a leg having one end provided two coaxial shafts 102 on each of which is mounted to pivot a wheel 103.
• Each wheel 103 comprises in a manner known per se a hub 104 mounted to pivot on the shaft 102 and a rim 105 connected to the hub 104 by a web 106.
• shafts 102 define a primary axis 107 of rotation of wheel 103.
• Wheels 103 are each equipped with a magnetic braking device.
• the magnetic braking device comprises mobile elements in rotation, or rotors 1, and fixed elements in rotation, or stators 2. More precisely here, the stators 2 and the rotors 1 are in the form of discs, coaxial with the wheel 103, therefore having central axes coinciding with the primary axis of rotation 107. The stators 2 and the rotors 1 are arranged in two triplets each forming a braking clearance I, II. Each braking set I, II comprises a rotor 1 disposed between two stators 2a, 2b each having a main face 2.1 extending opposite one of the main faces 1.1, 1.2 of the rotor 1. The faces 1.1, 1.2, 2.1 are parallel to each other.
• each set I, II therefore comprises a rotor 1, a stator 2a and a stator 2b.
• these characters a, b are used only when it is necessary to distinguish the stators 2 from one another.
• the stators 2 are linked in rotation to the shaft 102 or to the leg of the undercarriage 101, here via a torsion tube 3 (or torque tube) secured to an actuator-carrying plate 7 rigidly fixed to the shaft 102, while the rotors 1 are connected in rotation to the wheel 103, here to the rim 105 of the wheel 103, in a manner known per se.
• each rotor 1 turns on itself around its central axis with respect to the stators 2a, 2b which frame it: during this movement of the rotor 1 in a circumferential direction, the main faces 1.1, 1.2 remain opposite the main blade faces 2.1, parallel thereto and separated by an e trefer.
• the stators 2a are located opposite the face
• the torsion tube 3 is provided with ribs to form slideways allowing each of the stators 2 to smooth without rotation on the torsion tube 3 in such a way that each stator 2 is movable in an axial direction of the torsion tube 3 between a first position in which the rotor 1 and the stator 2 are close together and have their main faces 1.1, 1.2,
• the braking device comprises an actuator, generally designated at 4, controllable by the pilot of the airplane in a manner known per se, to move the stators 2 between the two aforementioned positions.
• the actuator 4 comprises a plurality of transmission assemblies generally designated at 4a to move the stators 2a and a plurality of transmission assemblies generally designated at 4b to move the stators 2b.
• the transmission assemblies 4a are arranged alternately with respect to the transmission assemblies 4b.
• Each transmission assembly 4a comprises an operating bar 5a mounted on the torsion tube 3 to extend parallel to the primary axis of rotation 107 and to slide without rotation along said axis.
• the operating bar 5a is connected by a first mechanical connecting member 21a to a pinion 6a mounted in the actuator-carrying plate 7 by bearings to be fixed in translation and mobile in rotation around a secondary axis of rotation 6a' collinear to the longitudinal axis of the operating bar 5a.
• the first mechanical connection member 21a comprises a thread made on the end of the operating bar 5a and a thread made in the pinion 6a and receiving the end of the operating bar 5a in such a way that a rotation of the pinion 6a causes a translation of the operating bar 5a in one direction or the other, depending on the direction of rotation of the pinion 6a.
• the pinions 6a mesh with an internal toothing of a crown 8 which is centered on the primary axis of rotation 107 and which surrounds the pinions 6a.
• the means for driving the drive pinion in rotation are not shown but can be of any type (gear, belt, chain, rack, etc.).
• the operating bar 5a is connected by a second member mechanical connection 22a to each stator 2a.
• Each second mechanical connecting member 22a comprises two glue lugs extending radially projecting from the operating bar 5a to accommodate between them a portion of the internal circumference of one of the stators 2a and form abutments for driving the stators 2a between their two axial positions.
• Each transmission assembly 4b comprises an operating bar 5b mounted on the torsion tube 3 to extend parallel to the primary axis of rotation 107 and to slide without rotation along said axis.
• the operating bar 5b is connected by a first mechanical connecting member 21b to a pinion 6b mounted in the actuator-carrying plate 7 by bearings to be fixed in translation and mobile in rotation around a secondary axis of rotation 6b' collinear to the longitudinal axis of the operating bar 5b.
• the first mechanical connecting member comprises a thread made on the end of the operating bar 5b and a thread made in the pinion 6b and accommodating the end of the operating bar 5a in such a way that a rotation of the pinion 6b causes a translation of the operating bar in one direction or the other, depending on the direction of rotation of the pinion 6b.
• Pinions 6b mesh with the internal toothing of crown 8.
• the operating bar 5b is connected by a second mechanical connecting member to each stator 2b.
• Each second mechanical connecting member comprises two collars 20b extending radially projecting from the operating bar 5b to accommodate between them a portion of the internal circumference of one of the stators 2b and to form abutments for driving the stators 2b between their two axial positions.
• the helical connection formed between the pinions 6b and the operating bars 5b is in the opposite direction to the connection helical formed between the pinions 6a and the operating bars 5a. It is therefore understood that, when crown 8 rotates in one direction, it drives pinions 6a, 6b in the same direction; on the other hand, the operating bars 5a move in a direction opposite to the direction of movement of the operating bars 5b.
• a rotation of the crown 8 in a first direction therefore causes a rimpedement of the stators 2a with the stators 2b (the air gap e with the rotors 1 decreases) while a rotation of the crown 8 in a second direction causes a distance of the stators 2a with the stators 2b respectively (the air gap e with the rotors 1 increases).
• the rotors 3 are here made of steel or cast iron so that their faces 1.1, 1.2 can form braking surfaces as will be explained later. Any other electrically conductive material capable of performing this function can be used.
• the rotors 3 may comprise a copper disc whose main faces are covered with a layer of steel or cast iron to form the braking surfaces, which makes it possible to have a good coefficient of friction with the lining while by increasing the calorific mass so as to have effective braking despite the increase in temperature occasioned by the friction of the lining on the braking surface.
• each stator 2 of each triplet comprises a plurality of magnets capable of generating eddy currents in the rotor 1 when the stator 2 is in an intermediate position between the first and second positions and that the rotor 3 pivots opposite the stator 2.
• the magnets here based on rare earths, are for example 16 in number and are preferably fixed on a support 200 made of magnetic steel, or even on a non-magnetic support.
• the plurality of magnets includes first magnets 11, 13 having a first magnetization vector substantially perpendicular to the main face 2.1 and being separated in pairs by a second magnet 12, 14 having a second magnetization vector substantially perpendicular to the first magnetization vectors of the first two magnets 11, 13 between which is the second magnet
• the magnetization vector indicates the direction of the magnetic field generated by a magnet and extends in the magnet from the South pole to the North pole. More specifically, the magnets 11, 12, 13, 14 have the shape of angular sectors and have a length L measured along a radial direction of the stator 2 and an average width 1 measured along a locally tangential direction of the discs (this is that is to say perpendicular to the direction of the length L) half of said length L.
• the lengths L and widths 1 are measured in directions locally parallel to the facing surfaces (the main faces 1.1, 1.2, 2.1).
• the magnets 11, 12, 13, 14 are arranged in a Halbach pattern, alternately in the circumferential direction of the stator 2 as follows: a magnet 11, a magnet 12, a magnet 13, a magnet 14, a magnet 11, a magnet 12, a magnet 13, a magnet 14 and so on...In this case: - each magnet 11 has its magnetization vector which comes out of the main face 2.1 (its North pole opens onto the main face 2.1 ),
• each magnet 12 has its magnetization vector which extends from the neighboring magnet 11 to the neighboring magnet 13,
• each magnet 13 has its magnetization vector which enters the main face 2.1 (its South pole opens on the main face 2.1),
• each magnet 14 has its magnetization vector which extends from the neighboring magnet 11 to the magnet 13 neighbor.
• each magnet 11 of one of the two stators 2 faces a magnet 13 of the other of the two stators 2, and vice versa, so that all the magnets 11 face magnets 13 and attract each other mutually. through the rotor 3, which improves performance.
• the magnets 12, 14 arranged on each side of the same magnet 11 have their magnetization vector oriented in opposite directions.
• each magnet 11 of one of the two stators 2 faces a magnet 13 of the other of the two stators 2, and vice versa, so that all the magnets 11 face magnets 13 and attract each other mutually. through the rotor 3, which improves performance.
• the magnets 12, 14 arranged on each side of the same magnet 11 have their magnetization vector oriented in opposite directions.
• each magnet 11 of one of the two stators 2 faces a magnet 13 of the other of the two stators 2, and vice versa, so that all the magnets 11 face magnets 13 and attract each other mutually. through the rotor 3, which improves performance.
• the magnets 12, 14 arranged on each side of the same magnet 11
• the lengths Lu, L12, L13, L14 of the magnets 11, 12, 13, 14 are identical to each other.
• the lengths Lu, L 13 of the magnets 11, 13 are identical to each other and the lengths L 12 , L 14 of the magnets 12, 14 are identical to each other.
• the lengths Lu, L 13 of the magnets 11, 13 are greater than the lengths L 12 , L 14 of the magnets 12, 14.
• the magnets 12, 14 occupy parallel to the face main 2.1 a smaller surface than that of the magnets 11, 13.
• the arrangement of the magnets 11, 12, 13, 14 makes it possible to optimize and concentrate the magnetic flux produced by the magnets 11, 13 by reducing the return path of the magnetic flux which passes through the magnets 12, 14 and not through their support whose mass can be reduced since it does not need to provide a magnetic flux conduction function.
• the two embodiments above both allow an increase in the braking torque supplied while limiting the mass and the size of the device.
• the first embodiment of the stator allows a higher magnetic braking torque than the second embodiment but on the other hand has a greater weight.
• the magnets 11, 12, 13, 14 have their surface, opposite the support 200, covered with an intermediate layer 201 itself covered with a friction lining 202 having, at opposite the intermediate layer 201, a surface forming the face 2.1 of the stator 2.
• the intermediate layer 201 interposed between the magnets 11, 12, 13, 14 and said friction lining 202, is made of non-magnetic steel and has a sufficient thickness to allow it to form a heat shield between the friction lining 202 and the magnets. 11, 12, 13, 14.
• the magnets will obviously be chosen to have a limited loss of magnetization at the operating temperatures of the magnetic braking device: in all cases, the Curie temperature of the magnets used must be much higher than the operating temperatures of the braking device. magnetic braking regardless of the braking mode used.
• the intermediate layer 201 also ensures protection of the magnets against shocks and promotes the retaining the magnets on the support 200.
• the intermediate layer 201 can be screwed, riveted, or welded onto the support 200 in such a way that the magnets are preferably trapped between the intermediate layer 201 and the support 200.
• the friction linings 202 are made of non-magnetic material (so as not to create a magnetic short-circuit) and preferably electrically insulating (to limit losses during magnetic braking).
• the friction lining 202 is for example fixed to the intermediate layer 201 by hot gluing or riveting. Such friction linings are known themselves.
• Each rotor 1 has a thickness such that a skin effect (otherwise called skin effect or Kelvin effect) is generated from each face 1.1 of the rotor 1 over more than half the thickness of the rotor 1 at least over a range of speeds possible relative rotor 1 with respect to the stators 2.
• the eddy currents generated from the two faces 1.1 will then circulate in the central part of each rotor 1, which will increase the braking torque.
• a “superposition of the skin effects” is thus obtained, the thickness of the rotor 1 being sufficiently small to obtain this effect while satisfying the thermal and mechanical stresses. In one example, this effect gives about 60% more performance.
• the control actuator is controlled to bring the stators 2 into an intermediate position between the first position and the second position, intermediate position in which the stators are sufficiently close to the rotors, without touching them, so that the magnets generate sufficient eddy currents in the rotors to cause the desired braking of the rotors, and - to interrupt the magnetic braking, the control actuator is controlled to bring the stators 2 into the second position, a position in which the sta tors are far enough from the rotors so that the magnets do not generate sufficient eddy currents in the rotors to cause significant braking of the rotors.
• the braking device according to the invention can be used to perform braking by friction.
• the control actuator is controlled to bring the stators 2 into the first position (closed position), position in which the braking surfaces 2.1 are in contact with the braking surfaces 1.1, 1.2 and are maintained in this position by the magnets 11, 12, 13, 14 even in the absence of power to the actuator, and
• the control actuator is driven to bring the stators 2 to the second position, position in which the braking surfaces 1.1, 1.2, 2.1 are no longer in contact with each other.
• the device comprises first axial stops connected in rotation and translation to the stators 2 and second axial stops connected in rotation and in translation to the rotor 1 to prevent contact of the faces 2.1 of the stators 2 with the faces
• the axial stops here comprise two pairs of crowns
• 211.1 has a planar annular face 211.1' extending perpendicular to the pivot axis and in front of the face
• the crown 211.2 has a planar annular face 211.2' extending perpendicularly to the pivot axis and in front of the face 1.2 of the rotor 1 with which it is secured .
• the flat annular faces 211.1', 211.2' form braking surfaces.
• Each stator 2 also comprises a crown 212 extending from an outer periphery of the support 200 surrounding the magnets 11, 12, 13, 14.
• Each crown 212 has a flat annular end face which extends perpendicularly to the axis of pivoting and is covered by a friction lining 213 whose free surface forms a braking surface 213'.
• the device of the invention can implement an actuator according to a second embodiment represented in FIGS. 10 and 11.
• the actuator 4 comprises as previously a plurality of transmission assemblies generally designated as 4a for moving the stators 2a and a plurality of transmission assemblies generally designated as 4b for moving the stators 2b.
• the transmission assemblies 4a are arranged alternately with respect to the transmission assemblies 4b.
• Each transmission assembly 4a comprises an operating bar 5a mounted on the torsion tube 3 to extend parallel to the primary axis of rotation 107 and pivot without sliding along said axis.
• the operating bar 5a is connected by a first mechanical connecting member 21a' to a pinion 6a mounted in the actuator-carrying plate 7 by bearings to be fixed in translation and mobile in rotation around a secondary axis of rotation 6a' collinear with the longitudinal axis of the operating bar 5a.
• the first mechanical link member 21a' ensures a recessed link of the end of the operating bar 5a in the pinion 6a.
• the first mechanical link member 21a' can be a weld, glue, interlocking, press fit, bolt, pin...
• the operating bar 5a, the first mechanical link member 21a' and the pinion 6a are in one piece.
• a rotation of the pinion 6a causes a rotation of the operating bar 5a in one direction or the other, depending on the direction of rotation of the pinion 6a.
• the pinions 6a mesh with an internal toothing of a crown which is centered on the primary axis of rotation 107 and which surrounds the pinions 6a.
• This crown is identical to crown 8 and is mounted and driven in rotation like the latter.
• the operating bar 5a is connected by a second mechanical connection member 22a' to each stator 2a.
• Each second mechanical connecting member 22a' comprises a thread extending around operating bar 5a and cooperating with a thread formed in the internal circumference of stator 2a.
• the two second mechanical connection members 22a' ensure a helical connection between the operating bar 5a and the stators 2a.
• Each transmission assembly 4b comprises an operating bar 5b mounted on the torsion tube 3 to extend parallel to the primary axis of rotation 107 and pivot without sliding along said axis.
• the operating bar 5b is connected by a first mechanical connecting member 21b' to a pinion 6b mounted in the actuator-carrying plate 7 by bearings to be fixed in translation and mobile in rotation around a secondary axis of rotation 6b' collinear with the longitudinal axis of the operating bar 5b.
• the first mechanical connecting member 21b' provides a recessed connection of the end of the operating bar 5b in the pinion 6b.
• the first mechanical connecting member can be a weld, glue, interlocking, a tight fit, a bolt, a pin...
• the operating bar 5b is in one piece with the pinion 6b.
• a rotation of the pinion 6b causes a rotation of the operating bar 5b in one direction or the other, depending on the direction of rotation of the pinion 6b.
• the pinions 6b mesh with an internal toothing of the aforementioned crown which surrounds the pinions 6a.
• the operating bar 5b is connected by a second mechanical connecting member 22b' to each stator 2b.
• Each second mechanical connecting member 22b' comprises a thread extending around the operating bar 5b and cooperating with a thread formed in the inner circumference of the stator 2b.
• the two second mechanical link members 22b' provide a helical connection between the control rod 5a and the stators 2b.
• the helical connections formed between the stators 2b and each operating bar 5b are in the opposite direction to the helical connection formed between the stators 2a and each operating bar 5a. It is therefore understood that when the crown rotates in one direction, it drives the pinions 6a, 6b and the operating bars 5a, 5b in the same direction; on the other hand, the stators 2a move in a direction opposite to the direction of movement of the stators 2b.
• a rotation of the crown in a first direction therefore causes a rimpedement of the stators 2a with the stators 2b respectively (the air gap with the rotors 1 decreases) while a rotation of the crown in a second direction causes a distance of the stators 2a d 'with the stators 2b respectively (the air gap with the rotors 1 increases).
• the device may have a structure different from that described.
• the magnets can be carried by the rotor instead of the stator, two rotors flanking a stator.
• the shape, arrangement and dimensions of the magnets may vary from those described.
• the magnets 11, 12, 13, 14 all have the same dimensions.
• the first magnets 11, 13 will represent approximately 70% of the surface of the element that carries them, but this is not compulsory.
• the first magnets 11, 13 having a first magnetization vector substantially perpendicular to the facing surfaces 1.1, 1.2, 2.1 and each of the second magnets 12, 14 having a second magnetization vector substantially perpendicular to the first magnetization vectors of the first two magnets between which it is located; and the magnets 11, 12, 13, 14 have widths such that the first magnets 11, 13 are spaced apart in pairs by a first distance less than a second distance separating the second magnets 12, 14 in pairs.
• Halbach pattern is not mandatory.
• the number of rotors and/or the number of stators may be different from those mentioned.
• each of the stators can be mounted on a sliding slide (without rotation) on the torque tube to be movable in an axial direction of the torque tube between a first position in which the rotor and the stator are in contact with one of the other and a second position in which the rotor 3 and the stator 2 are separated from each other.
• At least one electromechanical actuator controllable by the pilot of the aircraft in a manner known per se, moves the slide between the two aforementioned positions. It is understood that to cause friction braking, the electromechanical control actuators are driven to bring the stators into the first position and that, to interrupt friction braking, the electromechanical control actuators are driven to bring the stators into the second position. - position.
• the actuator according to the first embodiment can be modified.
• the pinions 6a are connected to the operating bars 5a by a helical connection in the same direction as that connecting the sprockets 6b to the operating bars 5b.
• the pinions 6a mesh with the internal teeth of a crown 8a dragged in rotation by a pinion 9a while the pinions 6b mesh with the internal teeth of a crown 8b driven in rotation by a pinion 9b.
• Crown 8b is superimposed on crown 8a, which is the crown closest to braking clearances A, B. Pinions 8a are therefore closer to stators 2al than pinions 8b.
• the motor pinions 9a, 9b drive the crowns 8a, 8b in opposite first directions to respectively bring each stator 2a closer to the rotor 1 and each stator 2b to the rotor 1 and in second opposite directions to separate respectively each stator 2a of rotor 1 and each stator 2b of rotor 1.
• crown 8 is eliminated.
• the adjacent sprockets 6a, 6b mesh with each other two by two.
• a motor pinion 9 meshes with one of the pinions 6b so that the movement which the motor pinion 9 communicates to said one of the pinions 6b is communicated step by step to the other pinions 6a, 6b.
• the actuator according to the second embodiment can also be modified. It is possible to have helical connections in opposite directions on the same operating bar, for example by attaching externally threaded bushings to the operating bar. The same bar maneuver can then move the two stators by the same clearance.
• the magnetic braking device according to the invention can be associated with a conventional friction braking device which comprises friction members, for example a stack of carbon discs, and a plurality of electromechanical actuators carried by a actuator holders.
• Each electromechanical actuator comprises an electric motor and a pusher adapted to be moved by the electric motor to press the stack of discs.
• the electromechanical actuator is thus intended to produce a controlled braking force on the stack of discs.
• a control mode for braking devices is for example known from document FR-A-2953196.
• the axial stops may have a structure different from that described.
• the axial stops linked in rotation and axial translation to the rotor can for example be separated from the rotors and fixed directly to the rim.

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• Engineering & Computer Science (AREA)
• Mechanical Engineering (AREA)
• General Engineering & Computer Science (AREA)
• Transportation (AREA)
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• Aviation & Aerospace Engineering (AREA)
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• Electromagnetism (AREA)
• Braking Arrangements (AREA)
• Dynamo-Electric Clutches, Dynamo-Electric Brakes (AREA)

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• 2021
  • 2021-07-14 FR FR2107629A patent/FR3125367A1/fr active Pending
• 2022
  • 2022-07-13 WO PCT/EP2022/069685 patent/WO2023285569A1/fr active Application Filing
  • 2022-07-13 US US18/578,786 patent/US20240317389A1/en active Pending
  • 2022-07-13 EP EP22751667.1A patent/EP4371223A1/de active Pending
  • 2022-07-13 CN CN202280049997.2A patent/CN117642972A/zh active Pending
  • 2022-07-13 CA CA3225335A patent/CA3225335A1/fr active Pending

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