Classifications

• • H—ELECTRICITY
  • H02—GENERATION; CONVERSION OR DISTRIBUTION OF ELECTRIC POWER
  • H02K—DYNAMO-ELECTRIC MACHINES
  • H02K1/00—Details of the magnetic circuit
  • H02K1/06—Details of the magnetic circuit characterised by the shape, form or construction
  • H02K1/12—Stationary parts of the magnetic circuit
  • H02K1/14—Stator cores with salient poles
  • H02K1/146—Stator cores with salient poles consisting of a generally annular yoke with salient poles
• • H—ELECTRICITY
  • H02—GENERATION; CONVERSION OR DISTRIBUTION OF ELECTRIC POWER
  • H02K—DYNAMO-ELECTRIC MACHINES
  • H02K1/00—Details of the magnetic circuit
  • H02K1/06—Details of the magnetic circuit characterised by the shape, form or construction
  • H02K1/22—Rotating parts of the magnetic circuit
  • H02K1/26—Rotor cores with slots for windings
• • H—ELECTRICITY
  • H02—GENERATION; CONVERSION OR DISTRIBUTION OF ELECTRIC POWER
  • H02K—DYNAMO-ELECTRIC MACHINES
  • H02K13/00—Structural associations of current collectors with motors or generators, e.g. brush mounting plates or connections to windings; Disposition of current collectors in motors or generators; Arrangements for improving commutation
• • H—ELECTRICITY
  • H02—GENERATION; CONVERSION OR DISTRIBUTION OF ELECTRIC POWER
  • H02K—DYNAMO-ELECTRIC MACHINES
  • H02K23/00—DC commutator motors or generators having mechanical commutator; Universal AC/DC commutator motors
  • H02K23/40—DC commutator motors or generators having mechanical commutator; Universal AC/DC commutator motors characterised by the arrangement of the magnet circuits
  • H02K23/42—DC commutator motors or generators having mechanical commutator; Universal AC/DC commutator motors characterised by the arrangement of the magnet circuits having split poles, i.e. zones for varying reluctance by gaps in poles or by poles with different spacing of the air gap
• • H—ELECTRICITY
  • H02—GENERATION; CONVERSION OR DISTRIBUTION OF ELECTRIC POWER
  • H02K—DYNAMO-ELECTRIC MACHINES
  • H02K3/00—Details of windings
  • H02K3/04—Windings characterised by the conductor shape, form or construction, e.g. with bar conductors
  • H02K3/18—Windings for salient poles
• • H—ELECTRICITY
  • H02—GENERATION; CONVERSION OR DISTRIBUTION OF ELECTRIC POWER
  • H02K—DYNAMO-ELECTRIC MACHINES
  • H02K7/00—Arrangements for handling mechanical energy structurally associated with dynamo-electric machines, e.g. structural association with mechanical driving motors or auxiliary dynamo-electric machines
  • H02K7/006—Structural association of a motor or generator with the drive train of a motor vehicle
• • H—ELECTRICITY
  • H02—GENERATION; CONVERSION OR DISTRIBUTION OF ELECTRIC POWER
  • H02K—DYNAMO-ELECTRIC MACHINES
  • H02K2201/00—Specific aspects not provided for in the other groups of this subclass relating to the magnetic circuits
  • H02K2201/03—Machines characterised by aspects of the air-gap between rotor and stator
• • H—ELECTRICITY
  • H02—GENERATION; CONVERSION OR DISTRIBUTION OF ELECTRIC POWER
  • H02K—DYNAMO-ELECTRIC MACHINES
  • H02K2205/00—Specific aspects not provided for in the other groups of this subclass relating to casings, enclosures, supports
  • H02K2205/12—Machines characterised by means for reducing windage losses or windage noise

Definitions

• the invention relates to a starter motor for a motor vehicle engine equipped with a rotary electric machine with indented pole poles improved and the corresponding polar mass.
• the invention finds a particularly advantageous, but not exclusive, application with starter systems so-called "stop and start” for stopping and restarting the engine of the vehicle according to particular traffic conditions.
• a starter provided with a launcher capable of transmitting a rotation energy of the starter to a crankshaft of the engine through a crown starting.
• This launcher is mounted on a drive shaft.
• a speed reducer is interposed between this drive shaft and the shaft of an electric motor.
• This electric motor comprises firstly, a rotor, also called armature and secondly, a stator, also called inductor, mounted coaxially around the rotor.
• the rotor comprises a body in the form of a pack of sheets provided with notches each delimited by two successive teeth.
• the rotor further includes wires wound in the slots to form the rotor winding.
• the stator has at the location of each magnetic pole a radially protruding pole mass around which is wound an inductor wire.
• These polar masses are generally in parallelepiped shape with a curvature adapted to the radius of the armature in order to leave a gap between the armature and the magnetic poles weak and constant so as to make the electromagnetic conversion as effective as possible.
• the rotor is provided with a collector comprising a plurality of contact pieces electrically connected to the conductors of the rotor winding.
• a group of brushes is provided for the power supply of the winding, some brushes being connected to the starter mass and others being connected to an electrical terminal of a contactor. The brushes rub on the collector blades when the rotor is rotating to allow the power supply of the rotor by switching the electric current.
• collector brush frequency One of the main sources of noise from the electric motor is the "collector brush frequency” and its harmonics. This frequency generally close to a hissing sound is the multiple of the armature rotation frequency and the number of collector blades (and therefore the number of rotor teeth). This source has two origins: a mechanism due to the friction of the brushes on the collector of the armature, the other electromagnetic.
• the rotor is subjected to electromagnetic forces which comprise tangential components (which are at the origin of the rotation of the armature), but also radial components corresponding to a so-called “rotating" force which are likely to create deformations of the parts to which they apply, including the poles and the breech of the starter motor. These deformations are then at the origin of the noise which can be all the stronger as the torque provided by the starter is important.
• the invention aims to remedy this drawback effectively by proposing a starter for a motor vehicle engine comprising a rotating electrical machine provided with a rotor and a stator comprising a plurality of magnetic poles arranged on an inner circumference of a cylinder head.
• each magnetic pole is protruding from the yoke surrounded by a winding, and that an axial air gap between a circumferential surface of at least two magnetic poles facing a circumferential surface of said rotor and a radius circle of the outside of the rotor varies by at least 1 mm.
• breech means the portion of the stator for passing a flux between two magnetic poles.
• each magnetic pole is constituted by a polar mass mounted against the stator yoke.
• the stator comprises a stack of laminations forming the yoke and the different magnetic poles.
• the magnetic pole comprises a groove forming the variation of the gap.
• the air gap varies by at least 1 mm on a circumferential end of its circumferential surface.
• the surface in which the gap varies circumferentially also varies axially.
• each pole mass having a development said gap is greater between an area of said expansion and said rotor between a central portion of the magnetic pole and said rotor.
• an increase in said gap is obtained by a discontinuity of an inner face of at least one magnetic pole situated opposite said rotor.
• the discontinuity is defined by at least one plane surface formed in the internal face of a magnetic pole.
• said flat surface is formed in said development.
• said planar surface is substantially in the foreground.
• said polar masses are reported relative to said yoke of said stator. This facilitates the mounting of the stator.
• said starter is configured to operate at a current of the order of 600A for a cold start of the engine or a current of the order of 250A for a start of the engine in stop mode and restart of the engine.
• said rotor has 19 notches for receiving conductors for the formation of a rotor winding.
• the subject of the invention is also a polar mass belonging to an electric motor starter motor motor inductor, characterized in that it comprises an internal face intended to be situated facing a rotor of said electric motor having a discontinuity breaking a gap. regularity of an arc defining a portion of said inner face.
• FIG. 1 shows a longitudinal sectional view of a thermal engine starter according to the present invention
• FIG. 2 represents, according to a first embodiment, a schematic view in cross section of the electric motor used with the starter according to the present invention
• FIG. 3 shows according to a first embodiment a detailed side view of a polar mass used with the electric motor of the starter according to the present invention
• FIGS. 4a and 4b respectively show graphical representations of the relative evolutions of the engine torque and of the amplitude of the rotating force at the origin of the noise, as a function of the height of a chamfer formed in the polar mass for a current of battery of the order of 600A and 250A.
• FIG. 5 shows, in another embodiment, a detailed side view of a polar mass used with the electric motor of the starter according to the present invention
• magnetic pole and magnetic mass a pole and respectively a magnetic mass of the stator.
• the starter 1 comprises a drive shaft 2, a launcher 3 mounted on the shaft 2 and an electric motor 5 described in more detail hereinafter composed of an inductor stator 8 and an armature rotor 9 mounted coaxially along an axis X.
• the stator 8 surrounds the rotor 9 integral with a shaft 14.
• the motor 5 comprises a carcass 10 mounted on a metal support 12 of the starter 1 intended to be fixed on a fixed part of the motor vehicle.
• An epicyclic gear type speed reducer 13 is preferably interposed between a rear end of the drive shaft 2 and the shaft 14 of the electric motor 5.
• Brushes 17 rub on conductive blades January 8 of a manifold 20 to supply the rotor winding.
• the brushes 17 belong to a brush holder 23 equipped with guiding cages and receiving brushes 17. These brushes 17 are biased towards the conductive blades 18 by resilient means 25 of the spring type.
• the brush holder 23 is secured to a rear flange 24 having in the central portion a housing for mounting a needle bearing. The bearing of the rear flange 24 is used for rotatably mounting one end of the shaft 14 of the electric motor 5.
• the starter 1 also comprises an electromagnetic contactor 29 extending parallel to the electric motor 5 by being radially implanted above it.
• the contactor 29 has a metal tank 30 carried by the support 12, and equipped with an excitation coil 33 provided with at least one winding. A shoulder of the tank 30 makes it possible to ensure the axial setting of a fixed core 34.
• Terminals 37, 38 are shaped to each form a fixed contact inside the tank 30.
• One of the terminals 37 is intended to be connected to the positive terminal of the vehicle battery, the other terminal 38 is connected at the input of the inductor winding of the stator 8 and the brushes 17 of positive polarities.
• a movable core 40 is attracted by magnetic attraction towards the fixed core 34 to, on the one hand, act after catching a game on a rod 41 carrying a contact mobile 42 to cause the closure of the contacts of the contactor 29 and power the electric motor 5 of the starter 1, and secondly, actuate a control lever 45 of the launcher 3.
• the drive shaft 2 is rotatably mounted in a front bearing 46 of the support 12.
• This bearing 46 is constituted by way of example by a needle bearing or alternatively by a plain bearing.
• This shaft 2 carries at the front a stop 48 adjacent to the bearing 46 to limit the movement of the launcher 3.
• the launcher 3 is slidably mounted on the drive shaft 2, and comprises a drive pinion 50, a driver 51 configured to be actuated by the pivoting control lever 45, and a freewheel device 52, for example of the type with rollers installed between the driver 51 and the pinion 50.
• the upper end of the lever 45 is mounted in a known manner to articulation on a rod elastically connected to the movable core 40 via a spring, said spring against tooth, housed in the movable core 40.
• the driver 51 is internally provided with helical splines in complementary engagement with external helical teeth carried by the drive shaft 2.
• the launcher 3 is thus animated by a helical movement when it is moved. by the lever 45 towards the stop 48 to come, via its pinion 50, in engagement with the start ring of a heat engine 5 (not shown).
• freewheel device 52 can be replaced by a conical clutch device or a clutch provided with several friction discs, as described in the document FR2978500.
• launcher 3 variant is implanted outside the support 12.
• the rotor 9 comprises a body 58 in the form of a pack of sheets provided with notches 59 delimited each by two successive teeth 61.
• the body 58 has a central through opening 91 for mounting on the shaft 14 for example by press fitting.
• the rotor 9 further comprises son wound in the notches 59 to form the rotor winding 63.
• This coil 63 is in connection with the conductive blades 18 of the collector 20 integral with the shaft of the electric motor 5.
• the rotor 9 has for example an outer diameter of the order of 49.7mm.
• the stator 8 comprises a plurality of magnetic poles 65 arranged on an inner circumference of a yoke 66.
• Each pole 65 is constituted by a protruding polar mass 69 in the overall shape of a parallelepiped surrounded by a winding 70.
• Each winding 70 is retained radially by a development 73 of the polar mass 69.
• the Y axis of each winding 70 is radial with respect to the axis X of the stator 8.
• the inductor coil here comprises two pairs of windings 70 North and South which are each wound around a polar mass 69 integral with the cylinder head 66.
• Each winding 70 is composed of an electrical conductor traversed by a direct current.
• each added pole mass 69 is fixed against the internal circumference of the cylinder head 66 by means of a fixing screw 691 inserted in a through opening 692 formed in the polar mass 69.
• a fixing screw 691 inserted in a through opening 692 formed in the polar mass 69.
• the polar masses 69 are separated from an outer periphery of the rotor 9 by an air gap 76 which varies along its circumference.
• the variation of the air gap 76 which is the subject of the invention is of course greater than the variations of the air gap 76 due to the tolerance intervals involved in the production of the stator 8 and the rotor 9. Indeed, the variation of the gap 76 is at least one millimeter.
• the air gap 76 is greater between an area of the shoe 73 and the rotor 9 than between a central portion 77 of the pole mass 69 and the rotor 9 where it is for example about 0.65 mm.
• the increase in the air gap 76 is obtained by discontinuity of the internal faces 74 of the polar masses 69 situated opposite the rotor 9.
• This discontinuity breaks the regularity of the arc. of a circle defining a part of the internal face 74 of each polar mass 69.
• the discontinuity is defined by two flat surfaces 80 formed in the development 73 on the side of the longitudinal edges of said development 73.
• at least one part of the development 73 is not in the extension of the arc defining a portion of the internal face 74 corresponding.
• a first plane P1 is defined parallel to the axis X of the stator 8 passing through an outer end of a plane surface 80, and a second plane P2 parallel to the axis X passing through an intersection between a circle C1 corresponding to the an arc defining a portion of an inner face 74 and a third plane P3 perpendicular to the first plane P1 passing through said outer end of the flat surface 80.
• each flat surface 80 is in the first plane P1.
• each flat surface 80 can be inclined relative to the plane P1, as shown in broken lines.
• the discontinuity of the inner faces 74 may be obtained by any other shape, such as V-shaped or U-shaped surfaces, sawtooth or crenellated.
• the discontinuity can be achieved at least in part in the central portion 77 of each polar mass 69.
• FIGS. 4a and 4b show graphical representations of the evolution of the amplitude A1 of the torque produced by the motor 5 and the amplitude A2 of the opposite of the rotating force as a function of the height of the chamfer corresponding to the gap E between the first P1 and the second plane P2.
• the relative force represents this is the amplitude of the rotating force at the origin of the noise compared to the force generated without variation of the gap, by absence of without chamfer.
• an optimum gap E of the gap 76 between 1 is selected. 5 and 2.8mm.
• the stator comprises a stack of sheets forming the yoke 65 and the different magnetic poles.
• the surface in which the air gap varies according to the circumference also varies axially.
• the outer surface 80 varies radially.
• the outer surface 80 is in a plane intersecting the axis of the rotor.
• the surface 80 begins at an axial end of the magnetic pole as in the Figure 3 is finished at its other axial end closer to the rotor as represented by the dots identified 80.
• the gap 76 between a circumferential surface of at least two magnetic poles vis-à-vis a circumferential surface of said rotor and a circle of radius of the outside of the rotor 9 varies by through a groove.
• This groove may for example be located in the shoulders on the surface facing the rotor.
• the gap 76 between a circumferential surface of at least two magnetic poles vis-à-vis a circumferential surface of said rotor and a radius circle of the outside of the rotor 9 varies in the central zone 77. In this case, it varies through a groove located on the surface facing the rotor.
• the width L of the portion forming the variation in this case the groove, measured according to the circumference (a circular arc) of the inner face 74 represents at least 10% of its surface.
• the sum of the widths L of the plane surface 80 is close to 30% of the length of the surface facing the rotor.
• the width or sum of the widths of the parts forming the gap variation form more than 5% and less than 40%. Indeed, as can be seen in Figures 4a and 4b if it is too weak it does not produce an effect and if it is too high the effects fade.

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• Engineering & Computer Science (AREA)
• Power Engineering (AREA)
• Connection Of Motors, Electrical Generators, Mechanical Devices, And The Like (AREA)
• Iron Core Of Rotating Electric Machines (AREA)
• Motor Or Generator Cooling System (AREA)

Applications Claiming Priority (2)

Publications (1)

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ID=51167932

Family Applications (1)

Country Status (6)

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Family Cites Families (20)

• 2013
  • 2013-12-20 FR FR1363299A patent/FR3015799B1/fr active Active
• 2014
  • 2014-12-18 JP JP2016539317A patent/JP2017504750A/ja active Pending
  • 2014-12-18 WO PCT/FR2014/053426 patent/WO2015092298A2/fr not_active Ceased
  • 2014-12-18 CN CN201480068883.8A patent/CN105830319A/zh active Pending
  • 2014-12-18 US US15/104,783 patent/US20170005541A1/en not_active Abandoned
  • 2014-12-18 EP EP14830979.2A patent/EP3084938A2/de not_active Withdrawn

Non-Patent Citations (2)

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