WO2016045827A1 - Electric motor, preferably for a vehicle windscreen wiper - Google Patents

Electric motor, preferably for a vehicle windscreen wiper Download PDF

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Publication number
WO2016045827A1
WO2016045827A1 PCT/EP2015/067225 EP2015067225W WO2016045827A1 WO 2016045827 A1 WO2016045827 A1 WO 2016045827A1 EP 2015067225 W EP2015067225 W EP 2015067225W WO 2016045827 A1 WO2016045827 A1 WO 2016045827A1
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WO
WIPO (PCT)
Prior art keywords
brushholder
plate
electric motor
interference suppression
suppression coil
Prior art date
Application number
PCT/EP2015/067225
Other languages
French (fr)
Inventor
Siegfried Stefani
Original Assignee
Valeo Systèmes d'Essuyage
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Application filed by Valeo Systèmes d'Essuyage filed Critical Valeo Systèmes d'Essuyage
Publication of WO2016045827A1 publication Critical patent/WO2016045827A1/en

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Classifications

    • 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
    • H02K11/026—Suppressors associated with brushes, brush holders or their supports

Definitions

  • Electric motor preferably for a vehicle windscreen wiper
  • the invention relates to a electric motor, preferably for a vehicle windscreen wiper with a gear mechanism fitted thereto, comprising a housing for the electric motor and/or the gear mechanism and a brushholder plate, which is accommodated by the housing and to which are fixed at least one brush for the power supply of the electric motor and at least one interference
  • brushes are mounted on a brushholder plate in such a way that they slide on the periphery of the current transformer.
  • a conductor in particular a braided conductor or a stranded conductor, is fitted to a brush and is usually connected to the power supply connection of the electric motor via an interference suppression coil in order to suppress interference on the brush.
  • interference suppression coils also designated as interference suppression inductors
  • Interference suppression coils predominantly comprise a wire conductor having one or a plurality of turns around a longitudinal central axis, wherein a ferrite core can also be comprised, said ferrite core being introduced between the turns.
  • the wire conductor has a first electrical contact end for connection to the power supply connection of the electric motor and a second electrical contact end for connection to the conductor connected to the brush.
  • a brushholder plate For accommodating a brushholder plate, it is known to fix the latter in a housing which at least partly surrounds the electric motor and/or a gear mechanism of the electric motor, such that the brushholder plate can be arranged either in a motor housing, in a gear mechanism housing or else between the motor housing and the gear mechanism housing connected to the motor housing.
  • interference suppression coils are therefore mounted indirectly on the brushholder plate in this way by means of additional fixing means. Use is thus made of additional mounts and/or sleeves with which the interference suppression coil is fixed to the brushholder plate at least in sections.
  • the prior art has the disadvantage here that fixing interference suppression coils to a brushholder plate of electric motors firstly does not conform to, in particular economic, series production and secondly leads to uncertainties in the assembly process and also with regard to the functional reliability of the fixing or of the fixing means used during permanent operation of the electric motor.
  • What is particularly disadvantageous is that the number of parts is increased by additional mounts and/or sleeves.
  • the present invention is based on the object of providing an electric motor in which the fixing of the interference suppression coil to a brushholder plate is realized process-reliably and functionally reliably with low outlay in terms of production and assembly.
  • the intention is also to reduce the number of parts.
  • an electric motor comprises a housing for the electric motor and/or the gear mechanism and a brushholder plate, which is accommodated by the housing and to which are fixed at least one brush for the power supply of the electric motor and at least one interference suppression coil.
  • the interference suppression coil comprises a wire conductor having at least one turn about a longitudinal central axis, wherein the wire conductor has a first electrical contact end for connection to a power supply connection of the electric motor and a second electrical contact end for connection to a conductor connected to the brush, in particular a braided conductor or a stranded conductor.
  • the interference suppression coil is fixed directly to the brushholder plate by means of a joining connection.
  • the interference suppression coil is held exclusively by the at least one joining connection to the brushholder plate.
  • the joining connection by means of the wire conductor, which simultaneously forms the interference suppression coil, is thus self-supporting or self-fixing.
  • the longitudinal central axis of the interference suppression coil can also be bent.
  • the at least one interference suppression coil in the assembled state of the electric motor can be arranged relative to the brushholder plate in such a way that the longitudinal central axis is arranged in a parallel plane and at a distance from the longitudinal central plane of the brushholder plate.
  • an interference suppression coil can be fixed on an arbitrary side of a brushholder plate.
  • either one or a plurality of brushes together with at least one interference suppression coil can be arranged on a first side of a brushholder plate, or that at least one brush is fitted on the first side and at least one interference suppression coil is fitted on the opposite side. Any combinations are conceivable here.
  • an interference suppression coil to be fitted accessibly on an outer side of the electric motor - for example a side of the brushholder plate that faces away from the rotor - and for the current transformer and/or a gear mechanism together with one or a plurality of brushes to be arranged on the inner side of the housing - for example a side of the brushholder plate that faces the current transformer.
  • a brushholder plate can furthermore have any arbitrary shape and
  • the brushholder plate is not necessarily shaped in a planar or flat fashion, but rather can also be curved, angular and/or bent and also consist of one or a plurality of parts connected to one another.
  • the invention has the advantage here that either an interference suppression coil can be mounted on the brushholder plate without fixing means, that is to say in this respect has a self-fixing or self-supporting structure, or use can be made of fixing means, such as sleeves or mounts, which have
  • the invention also enables an advantageous separation between the mechanical fixing of the interference suppression coil to the brushholder plate and the electrical connection of the two contact ends of the wire conductor to the power supply connection and/or the connection to the conductor connected to a brush.
  • the influence of force moments on the electrical connections of the interference suppression coil, particularly in the case of vibrations is reduced or even completely ruled out, as a result of which the functional reliability and stability of the electric motor according to the invention are considerably improved.
  • This positive effect is also additionally reinforced by the fact that the turns of the
  • interference suppression coil in the assembled state of the electric motor bear directly against the brushholder plate.
  • One advantageous configuration of the invention is characterized in that the joining connection is embodied as a force-locking and/or positively locking connection.
  • the wire conductor can be embodied in such a way that the joining connection is obtainable by permanent reshaping of the wire
  • ..permanent means that the wire conductor is plastically deformable and, after the removal of the force required for deformation, preferably maintains the shape that it has been constrained to assume, without the action of external forces, during the operation of the electric motor.
  • the material of the wire conductor can be dimensioned in such a way that the joining connection according to the invention is releasable.
  • the reshaping can be carried out by e.g. mechanical folding, lock-forming, interlacing, punching, twisting, winding or split-pin fixing of at least one part of the wire conductor or the interference suppression coil.
  • the joining connection comprises at least one joining location at which the interference suppression coil between the two contact ends of the wire conductor is led through a perforation in the brushholder plate and is joined to the brushholder plate by reshaping of the wire conductor in the region of the joining location at said brushholder plate.
  • the perforation has a closed periphery.
  • marginally open perforations would also be conceivable.
  • At least one first and/or second contact end on the opposite side of the brushholder plate has an enlarged periphery, in particular by means of a coil- or knot-shaped reshaping, a twisting, a splaying, split-pin fixing and/or a torsion, such that said contact end prevents said contact end from being able to slide back into the perforation of the brushholder plate, whereby the interference suppression coil is secured against falling out of the brushholder plate, and is preferably also fixed to the brushholder plate in a clamped fashion.
  • the interference suppression coil of an electric motor between the two contact ends of the wire conductor forms at least one first U-shaped arc which has two substantially parallel limbs connected to one another by a vertex.
  • the interference suppression coil is fixed to the brushholder plate, in particular by a joining connection, such that it is only necessary to ensure the fixing of at least one U-shaped arc, fashioned in particular in a manner projecting from the interference suppression coil in a leg-like manner, to the brushholder plate, said arc having a correspondingly sufficient inherent stability for this purpose.
  • the two parallel limbs that is to say the first and second limbs, can preferably bear against one another in a frictionally locking manner, as a result of which the strength and the stiffness of the U-shaped arc are additionally reinforced as well.
  • the two parallel limbs of a first U-shaped arc at least in the end region of the at least one turn are arranged
  • the two parallel limbs that is to say the first and second limbs, can bear against one another in a frictionally locking manner, as a result of which the strength and the stiffness of the U-shaped arc are likewise additionally reinforced as well.
  • the two parallel limbs of a U-shaped arc at least in the end region of the at least one turn are arranged substantially in a plane parallel to the longitudinal central axis, preferably at a shortest distance from the longitudinal central axis, which corresponds to the radius of a turn closest to said
  • the interference suppression coil is fashioned in such a way that turns of the interference suppression coil are formed substantially between the first and a further, second U-shaped arc which is configured substantially like the first U-shaped arc.
  • This arrangement of U-shaped arcs substantially at the two outer turns of the interference suppression coil results in a particularly high stability of the interference suppression coil during the operation of the electric motor.
  • a ferrite core is introduced between the turns of the interference suppression coil and is secured against falling out and preferably axially fixed along the longitudinal central axis of the interference suppression coil.
  • This can be effected, in particular, by virtue of the fact that a limb of at least one of the two U-shaped arcs, the second electrical contact end and/or at least one section of the wire conductor of a U-shaped arc, which section is integrally formed on one of the limbs, are/is shaped in such a way that the opening cross sections of the turns of the interference suppression coil that are arranged in each case in front of and behind the ferrite core are closed or at least covered, such that the ferrite core can bear against the latter and cannot slide from the turns surrounding it.
  • At least one U-shaped arc projects from a first side of the brushholder plate through a first perforation in the brushholder plate to the opposite side of the brushholder plate relative to the first side of the brushholder plate, such that the interference suppression coil is fixable to the brushholder plate by means of this U-shaped arc by the joining connection.
  • the interference suppression coil is fixed to the brushholder plate in a clamped manner, wherein turns of the interference suppression coil substantially bear against the brushholder plate, such that they bear against the surface of the brushholder plate in a frictionally locking manner and no bending moments can act on the fixing of the interference suppression coil if the electric motor is caused to oscillate or vibrate.
  • the at least one turn of the interference suppression coil and the reshaped region - forming the at least one joining location - of the wire conductor are arranged on different sides of the brushholder plate and touch the brushholder plate there preferably directly in each case.
  • the U-shaped arc is also possible for the U-shaped arc to be reshaped at the opposite side of the brushholder plate relative to the at least one turn, preferably by virtue of the two parallel limbs of said arc being bent in sections substantially perpendicularly or parallel to the longitudinal central axis of the interference suppression coil.
  • the first electrical contact end of the wire conductor for connection to the power supply connection, has a connection section likewise consisting of an electrical conductor. Said connection section is led, in particular pressed, through a further, second perforation in the brushholder plate and on the opposite side of the
  • the brushholder plate is connected to the power supply connection, which is embodied in particular as an electrical connection terminal, preferably by clamping, soldering or welding.
  • no further, second perforation is comprised and the first electrical contact end is led together with a U-shaped arc through a first perforation to the opposite side of the brushholder plate and connected to the power supply connection, wherein the shape of two U-shaped arcs connected to one another via a respective limb, that is to say with an S-shape, arises in this case.
  • the limbs thereof preferably in turn bear against one another, thus resulting in a frictionally locking engagement of the individual limbs and hence a further stiffening or reinforcement of the fixing of the interference
  • a further advantageous configuration of the invention is distinguished by the fact that the first electrical contact end of the wire conductor is longer than the second electrical contact end and is preferably longer than the longitudinal extent of the interference suppression coil in the wound state.
  • the longer contact end can be introduced as a conductor formed integrally with the interference suppression coil, for example, into a preferably further connection terminal housing connected to the brushholder plate.
  • the invention also affords the advantage that solid contact terminals used previously for interconnection between the electrical connection terminals and the first electrical contact ends of the brush can be omitted and a direct connection between the connection terminal and the first electrical contact end can be produced by an electrical conductor which preferably consists of the same material as the wire conductor of the interference suppression coil or is shaped from the wire conductor of the interference suppression coil.
  • a method for producing or assembling an electric motor according to the invention can comprise the following steps:
  • the wire conductor has a first electrical contact end for connection to a power supply connection of the electric motor and a second electrical contact end for connection to a conductor connected to the brush, such as a braided conductor or a stranded conductor,
  • the last-mentioned step of producing the joining connection can preferably comprise the following steps:
  • Figure 1 shows a first embodiment of a brushholder plate of an electric motor according to the invention with two brushes and two interference suppression coils;
  • Figures 1 a and 1 b show a front view and a side view of a first embodiment of an interference suppression coil before assembly
  • Figures 1 c to 1 e show a front view, a side view and a perspective view of the interference suppression coil according to Figures 1 a and 1 b after assembly;
  • Figure 2 shows an exploded view of the brushholder plate according to Figure 1 ;
  • Figure 3 shows a rear side view of the brushholder plate according to Figure 1 ;
  • Figure 4 shows a cross-sectional view along the section A-A through the brushholder plate according to Figure 3;
  • Figure 5 shows a second embodiment of a brushholder plate of an electric motor according to the invention with two brushes and two interference suppression coils;
  • Figure 6 shows a perspective view of the brushholder plate
  • Figure 7 shows a plan view of a brushholder plate according to
  • Figure 8 shows an exploded view of the brushholder plate according to Figures 5 to 7;
  • Figures 9a and 9b show a front view and a side view of a second
  • Figures 9c to 9e show a front view, a side view and a perspective view of the interference suppression coil according to Figures 9a and 9b after assembly;
  • Figures 10a and 10b show a front view and a side view of a third embodiment of an interference suppression coil before assembly
  • Figures 10c to 10e show a front view, a side view and a perspective view of the interference suppression coil according to Figures 10a and 10b after assembly.
  • Figures 1 to 4 show a first embodiment of the invention on the basis of a preassembled brushholder plate 1 for incorporation into an electric motor according to the invention, said electric motor not being shown in the figures.
  • Said brushholder plate 1 is preferably accommodated and retained in a clamped manner between a gear mechanism housing and a motor housing (neither of which is shown in the figures).
  • the brushholder plate 1 For positioning in the gear mechanism housing, the brushholder plate 1 has a lug 18. Further lugs are shown in Figure 1 , and are not provided with reference signs for reasons of clarity.
  • Figure 1 shows a brushholder plate 1 configured in a ring-like fashion, wherein this shape can substantially correspond to the shape of the gear mechanism housing in which the brushholder plate is accommodated.
  • a brushholder plate can have any arbitrary shape and configuration and is preferably composed of an
  • the brushholder plate is not necessarily shaped in a planar or flat fashion, but rather can also be curved, angular and/or bent and also consist of one or a plurality of parts connected to one another.
  • the current transformer (not shown) of the electric motor extends through the round cutout 17 of the brushholder plate 1 , such that the brushes 2 and 2' fixed to the brushholder plate 1 , said brushes each being introduced in a casing 12 and 12', slide on the periphery of the current transformer.
  • the embodiment of a brushholder plate 1 for an electric motor according to the invention in accordance with Figure 1 furthermore shows two interference suppression coils 3 and 3' fixed to the brushholder plate 1 , said interference suppression coils each consisting of a wire conductor 3a and 3a' having a multiplicity of turns 3b and 3b' which are wound in each case around the longitudinal central axes A of the interference suppression coils.
  • interference suppression coils 3 and 3' have first electrical contact ends 3c and 3c', which (in accordance with Figure 2) are connected to contact bridges 13 and 13', which are led through an elongate perforation in the brushholder plate 1 and are electrically connected to a power supply connection 4 and 4' of the electric motor, that is arranged on the rear side of the brushholder plate 1 .
  • wire conductors 3a and 3a' in accordance with Figure 1 have a second electrical contact end 3d and 3d' for connection to a conductor connected to the brush 2 and 2', in particular a braided conductor or a stranded conductor.
  • the interference suppression coils 3 and 3' shown in Figure 1 respectively form between the two contact ends 3c and 3d and 3c' and 3d' a first and a second U-shaped arc 5 and 6 and 5' and 6' (not shown in Figure 1 ), by means of which the inference suppression coils 3 and 3' are fixed to the brushholder plate 1 .
  • Figures 1 a and 1 b in this respect show in detail the interference suppression coil 3 in the first embodiment of the invention according to Figures 1 to 4 in a non-assembled state.
  • two U-shaped arcs 5 and 6 are formed on the non-assembled interference suppression coil 3, said U-shaped arcs each having two substantially straight, parallel limbs 5a and 5b and 6a and 6b connected to one another respectively by a vertex 5c and 6c.
  • an interference suppression coil can also form in each case only a single U-shaped arc, by means of which the interference suppression coil is at least partly fixed to the brushholder plate 1 .
  • a U-shaped arc can be fixed to a brushholder plate by means of a joining connection of any type, in particular including by fixing in a mount, reshaping, bending, clamping, pressing, adhesive bonding, soldering and welding.
  • Figure 2 shows the brushholder plate 1 in accordance with Figures 1 to 4 in an exploded drawing.
  • the two U-shaped arcs 5 and 6 of the interference suppression coil 3, for the assembly thereof, are to be led from the front side, that is to say a first side 9a, of the brushholder plate 1 through first perforations 8 and 8' in the brushholder plate 1 to the opposite side 9b of the brushholder plate 1 relative to the first side 9a of the brushholder 1 , such that the ends of both U-shaped arcs 5 and 6 on the rear side at the brushholder plate 1 project from the leadthroughs 8 and 8', where the interference suppression coil 3 is fixable to the brushholder plate 1 by means of said U-shaped arcs 5 and 6.
  • any types of joining connections can be used for this purpose.
  • Figure 2 reveals one particularly preferred further development of a fixing on the basis of the interference suppression coil 3', which is fixable to the brushholder plate 1 in a clamped manner by means of the U-shaped arcs 5' and 6' by virtue of the U-shaped arcs 5' and 6' being reshaped at the opposite side 9b of the brushholder plate 1 , specifically by virtue of the fact that the two parallel limbs are to be bent over in sections substantially perpendicularly to the longitudinal central axis A of the interference
  • Figure 2 correspondingly shows the interference suppression coil already in the assembled form, that is to say with bent ends of the two U-shaped arcs 5' and 6'.
  • Figure 2 shows a preferred connection terminal housing, which is connectable or connected to the brushholder plate and which
  • contact bridges 13 and 13' and the electrical connection terminals 4 and 4' are furthermore preferably embodied as an insulation housing.
  • the contact bridges 13, 13' and the connection terminals 4, 4' are provided separately here and are produced for example from a sheet-metal section by a stamping and bending process.
  • Figure 1 c shows an interference suppression coil 3 in which the ends of the two U-shaped arcs 5 and 6 and the vertices 5c and 6c thereof of the interference suppression coil 3 in the assembled state of the interference suppression coil 3 or the electric motor are likewise angled, that is to say shaped in a manner bent perpendicularly to the longitudinal central axis A.
  • Figure 3 shows a rear side view 9b of the brushholder plate 1 according to Figure 1 , on which the interference suppression coils 3 and 3' are mounted by the U-shaped arcs being inserted into the correspondingly embodied perforations, wherein only the ends - bent transversely with respect to the longitudinal central axis A in accordance with Figures 1 c to 1 e - of the first U-shaped arc 5 and 6 of the first interference suppression coil 3 and of the second U-shaped arc 5' and 6' of the second interference suppression coil 3' are visible.
  • Figure 4 shows a cross section A-A through the brushholder plate 1 according to the arrows A-A from Figure 3.
  • the free end of the second U-shaped arc 6 is bent on the rear side 9b of the brushholder plate transversely with respect to the longitudinal central axis A of the interference suppression coil 3.
  • Figure 4 shows that the interference suppression coil 3 is fixed to the brushholder plate in a clamped manner, wherein turns 3b of the interference suppression coil 3 substantially bear directly against the brushholder plate 1 , such that they bear against the surface of the
  • the interference suppression coil 3 can also be fixed to the brushholder plate 1 in a pretensionned manner.
  • pretensioning and/or instead of a bending, to reshape the free end of a U-shaped arc in particular by crimping or pressing, or to fix it at the rear side using an arbitrary fixing means, for example using a pin introduced into an opening of the U-shaped arc, in such a way that the end of the U-shaped arc is secured against sliding out of the perforation in the brushholder plate.
  • Figures 5 to 8 show the further development of a brushholder plate 1 with two interference suppression coils 3 and 3' fixed thereto of an electric motor according to the invention.
  • the two interference suppression coils 3 and 3', apart from the first electrical contact ends 3c and 3c', are embodied in a manner corresponding to the interference suppression coils according to Figures 1 to 4 and are accordingly also fixed to the brushholder plate 1 in the circumferential direction radially within the inner and the outer edge of the brushholder plate.
  • the interference suppression coils 3 and 3' in accordance with Figures 5 to 8 have first electrical contact ends 3c and 3c' which are not connected to contact bridges, but rather are embodied as connection sections 15 and 15'.
  • the latter are preferably shaped from the same material as the wire conductor 3a or 3a' and/or from the wire conductor of the interference suppression coils 3 and 3', in particular integrally therewith, and are led through a second perforation 10 and 10' in the brushholder plate 1 .
  • said connection sections 15 and 15' are electrically and preferably mechanically connected to the power supply connections 4 and 4' of the electric motor.
  • Figure 6 shows the two connection sections 15 and 15' arranged at the first electrical contact ends 3c and 3c', said connection sections being led through the second perforations 10 and 10' in the brushholder plate 1 and being fixed to the two power supply connections 4 and 4' embodied as connection terminals, wherein Figure 6 shows one preferred embodiment without a connection terminal housing for accommodating the connection sections 15 and 15'. In principle, the second perforations could also be dispensed with.
  • Figures 7 and 8 show an embodiment with a connection terminal housing 14, which is designed for accommodating the connection sections 15 and 15' embodied integrally with the interference suppression coil 3, capacitors 1 1 and 1 1 ', and also for accommodating the connection terminals 4 and 4' which are to be connected to the connection sections 15 and 15' preferably by clamping, soldering or welding.
  • a tool e.g. for a welding tool
  • Figures 9a and 9b show a second embodiment of an interference suppression coil 3 according to the invention in a non-assembled state, that is to say a state not reshaped with regard to the production of the joining connection.
  • two U-shaped arcs 5 and 6 are formed on said non-assembled interference suppression coil 3, said U-shaped arcs each having two substantially straight, parallel limbs 5a and 5b and 6a and 6b connected to one another respectively by a vertex 5c and 6c, preferably integrally.
  • FIGS. 10a and 10b show in detail a second embodiment of an interference suppression coil 3 according to the invention in a non-assembled state.
  • two U-shaped arcs 5 and 6 are formed on the non-assembled interference suppression coil 3 in the end region on both sides of the turns of the interference suppression coil 3, said U-shaped arcs once again each having two substantially straight, parallel limbs 5a and 5b and 6a and 6b connected to one another respectively by a vertex 5c and 6c.
  • the respective two parallel limbs 5a and 5b of the first U-shaped arc 5 and the respective two parallel limbs 6a and 6b of the second U-shaped arc 6 in the non-assembled state are arranged substantially in a plane parallel to the longitudinal central axis A of the interference suppression coil 3, wherein the shortest, that is to say the horizontal, distance from the longitudinal central axis A corresponds to the radius of the turns 3b.
  • the two U-shaped arcs 5, 6 follow the winding direction of the turns and are thus arranged preferably parallel in the figures on different sides relative to a central plane, between the planes spanned by the individual U-shaped arcs 5, 6.
  • suppression coil 3 in the assembled state are aligned substantially in a plane perpendicular to the longitudinal central axis A, to be precise towards one another, thus resulting in the possibility of an improved, braced fixing of an interference suppression coil to the brushholder plate.
  • Figures 1 e, 9e and 10e furthermore show one preferred further development of the invention in which a ferrite core 16 is introduced between the turns 3b of the interference suppression coil 3 and is axially fixed along the longitudinal central axis A.
  • a ferrite core 16 is introduced between the turns 3b of the interference suppression coil 3 and is axially fixed along the longitudinal central axis A.
  • the turn which is in each case directly adjacent to the U-shaped arc 5, 6 is embodied as a partial turn, e.g. as a half turn, relative to a full turn, and runs substantially in the radial direction of the turn as seen substantially in the viewing direction of the longitudinal central axis A.
  • the ferrite core 16 is axially fixed by virtue of the fact that an integrally formed section 7 of the wire conductor 3a is in each case fitted to the limbs 5b and 6a of the U-shaped arcs 5 and 6 and shaped in such a way that the opening cross sections of the turns of the interference suppression coil 3 that are arranged in each case in front of and behind the ferrite core are covered, such that the ferrite core 16 likewise bears against the latter and cannot slide from the turns 3b surrounding it.
  • the invention advantageously enables improved, in particular simplified, assembly and ensures an increased reliability during the assembly process.
  • a brushholder plate 1 is preassembled by at least one of the above embodiments of an interference suppression coil 3 being fixed thereto.
  • one or a plurality of U-shaped arcs 5 and 6 of the interference suppression coil 3 to be fixed are introduced, in particular plugged or press-fitted, from a first side 9a of a brushholder plate 1 at least in sections into perforations 8 and 8' of the brushholder plate 1 , such that preferably the turns of the interference suppression coil 3 can bear at least partly against the surface of the brushholder plate 1 and/or the
  • interference suppression coil 3 bears against the latter in a pretensioned manner.
  • the ends of the U-shaped arcs 5 and 6 are to be fixed with a joining connection, in particular by the free ends of the
  • connection section 10 of a conductor is fitted and/or is to be led through a second perforation 10 to the rear side 9b of the brushholder plate 1 and is to be fixed to a connection terminal, preferably by welding, soldering or clamping.

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  • Electromagnetism (AREA)
  • Engineering & Computer Science (AREA)
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Abstract

The invention relates to an electric motor, particularly for a vehicle windscreen wiper with a gear mechanism fitted thereto, comprising a housing for the electric motor and/or the gear mechanism and a brushholder plate, which is accommodated by the housing and to which are fixed at least one brush for the power supply of the electric motor and at least one interference suppression coil consisting of a wire conductor having at least one turn about a longitudinal central axis, wherein the wire conductor has a first electrical contact end for connection to a power supply connection of the electric motor and a second electrical contact end for connection to a conductor connected to the brush, in particular a braided conductor or a stranded conductor, wherein the interference suppression coil is fixed directly to the brushholder plate by means of a joining connection.

Description

Electric motor, preferably for a vehicle windscreen wiper
Prior Art
The invention relates to a electric motor, preferably for a vehicle windscreen wiper with a gear mechanism fitted thereto, comprising a housing for the electric motor and/or the gear mechanism and a brushholder plate, which is accommodated by the housing and to which are fixed at least one brush for the power supply of the electric motor and at least one interference
suppression coil.
In the case of electric motors having brushes for the power supply of the current transformer (commutator) of the electric motor, that is to say of the rotor, brushes are mounted on a brushholder plate in such a way that they slide on the periphery of the current transformer. In this case, a conductor, in particular a braided conductor or a stranded conductor, is fitted to a brush and is usually connected to the power supply connection of the electric motor via an interference suppression coil in order to suppress interference on the brush. Consequently, in the case of such electric motors, one or a plurality of interference suppression coils, also designated as interference suppression inductors, are also fitted to the brushholder plate.
Interference suppression coils predominantly comprise a wire conductor having one or a plurality of turns around a longitudinal central axis, wherein a ferrite core can also be comprised, said ferrite core being introduced between the turns. In this case, the wire conductor has a first electrical contact end for connection to the power supply connection of the electric motor and a second electrical contact end for connection to the conductor connected to the brush.
For accommodating a brushholder plate, it is known to fix the latter in a housing which at least partly surrounds the electric motor and/or a gear mechanism of the electric motor, such that the brushholder plate can be arranged either in a motor housing, in a gear mechanism housing or else between the motor housing and the gear mechanism housing connected to the motor housing.
In the case of electric motors of the type described in the introduction, interference suppression coils are therefore mounted indirectly on the brushholder plate in this way by means of additional fixing means. Use is thus made of additional mounts and/or sleeves with which the interference suppression coil is fixed to the brushholder plate at least in sections.
Furthermore, it is also customary to weld or solder the first contact end of the wire conductor to contact bridges of the power supply connection of the electric motor, such that the interference suppression coil is at least partly retained by a contact bridge.
The prior art has the disadvantage here that fixing interference suppression coils to a brushholder plate of electric motors firstly does not conform to, in particular economic, series production and secondly leads to uncertainties in the assembly process and also with regard to the functional reliability of the fixing or of the fixing means used during permanent operation of the electric motor. What is particularly disadvantageous is that the number of parts is increased by additional mounts and/or sleeves.
Disclosure of the Invention
Therefore, the present invention is based on the object of providing an electric motor in which the fixing of the interference suppression coil to a brushholder plate is realized process-reliably and functionally reliably with low outlay in terms of production and assembly. In particular, the intention is also to reduce the number of parts.
In the case of an electric motor of the type described in the introduction, this object is achieved according to the invention by virtue of the fact that an electric motor comprises a housing for the electric motor and/or the gear mechanism and a brushholder plate, which is accommodated by the housing and to which are fixed at least one brush for the power supply of the electric motor and at least one interference suppression coil.
According to the invention, the interference suppression coil comprises a wire conductor having at least one turn about a longitudinal central axis, wherein the wire conductor has a first electrical contact end for connection to a power supply connection of the electric motor and a second electrical contact end for connection to a conductor connected to the brush, in particular a braided conductor or a stranded conductor. In this case, the interference suppression coil is fixed directly to the brushholder plate by means of a joining connection.
In this case, the interference suppression coil is held exclusively by the at least one joining connection to the brushholder plate. The joining connection by means of the wire conductor, which simultaneously forms the interference suppression coil, is thus self-supporting or self-fixing.
The longitudinal central axis of the interference suppression coil can also be bent. Independently thereof, the at least one interference suppression coil in the assembled state of the electric motor can be arranged relative to the brushholder plate in such a way that the longitudinal central axis is arranged in a parallel plane and at a distance from the longitudinal central plane of the brushholder plate.
A joining connection in the sense of the invention should initially be
understood to mean any positively locking, frictionally locking and/or cohesive connection, in particular connections produced by clipping, adhesive bonding, welding, soldering, pressing, riveting, pinning and screwing. However, for direct fixing, a connection is understood which manages without further aids and manages for example by clamping, reshaping and/or bending of the wire conductor, as will be explained in even more detail below. In this case, it is also within the scope of the invention that an interference suppression coil can be fixed on an arbitrary side of a brushholder plate. That is to say that either one or a plurality of brushes together with at least one interference suppression coil can be arranged on a first side of a brushholder plate, or that at least one brush is fitted on the first side and at least one interference suppression coil is fitted on the opposite side. Any combinations are conceivable here.
In this respect, it is also possible for an interference suppression coil to be fitted accessibly on an outer side of the electric motor - for example a side of the brushholder plate that faces away from the rotor - and for the current transformer and/or a gear mechanism together with one or a plurality of brushes to be arranged on the inner side of the housing - for example a side of the brushholder plate that faces the current transformer.
A brushholder plate can furthermore have any arbitrary shape and
configuration. In particular, the brushholder plate is not necessarily shaped in a planar or flat fashion, but rather can also be curved, angular and/or bent and also consist of one or a plurality of parts connected to one another.
The invention has the advantage here that either an interference suppression coil can be mounted on the brushholder plate without fixing means, that is to say in this respect has a self-fixing or self-supporting structure, or use can be made of fixing means, such as sleeves or mounts, which have
correspondingly reduced dimensions and which have to neither accommodate nor stabilize the interference suppression coil.
Consequently, on account of the invention, fixing means can be saved or at least the complexity and the costs for fixing with fixing means for an interference suppression coil can be correspondingly reduced, and the fixing and the stability of interference suppression coils in electric motors can be improved. In particular, the invention also enables an advantageous separation between the mechanical fixing of the interference suppression coil to the brushholder plate and the electrical connection of the two contact ends of the wire conductor to the power supply connection and/or the connection to the conductor connected to a brush. On account of this decoupling of mechanical and electrical connection of the interference suppression coil, the influence of force moments on the electrical connections of the interference suppression coil, particularly in the case of vibrations, is reduced or even completely ruled out, as a result of which the functional reliability and stability of the electric motor according to the invention are considerably improved. This positive effect is also additionally reinforced by the fact that the turns of the
interference suppression coil in the assembled state of the electric motor bear directly against the brushholder plate.
One advantageous configuration of the invention is characterized in that the joining connection is embodied as a force-locking and/or positively locking connection.
In this case, the wire conductor can be embodied in such a way that the joining connection is obtainable by permanent reshaping of the wire
conductor. In this case, ..permanent" means that the wire conductor is plastically deformable and, after the removal of the force required for deformation, preferably maintains the shape that it has been constrained to assume, without the action of external forces, during the operation of the electric motor. In this case, the material of the wire conductor can be dimensioned in such a way that the joining connection according to the invention is releasable. The reshaping can be carried out by e.g. mechanical folding, lock-forming, interlacing, punching, twisting, winding or split-pin fixing of at least one part of the wire conductor or the interference suppression coil.
One advantageous configuration of the invention is characterized in that the joining connection comprises at least one joining location at which the interference suppression coil between the two contact ends of the wire conductor is led through a perforation in the brushholder plate and is joined to the brushholder plate by reshaping of the wire conductor in the region of the joining location at said brushholder plate. In principle, the perforation has a closed periphery. However, marginally open perforations would also be conceivable. For reshaping the wire conductor, preferably at least one first and/or second contact end on the opposite side of the brushholder plate has an enlarged periphery, in particular by means of a coil- or knot-shaped reshaping, a twisting, a splaying, split-pin fixing and/or a torsion, such that said contact end prevents said contact end from being able to slide back into the perforation of the brushholder plate, whereby the interference suppression coil is secured against falling out of the brushholder plate, and is preferably also fixed to the brushholder plate in a clamped fashion.
In accordance with one embodiment of the invention, the interference suppression coil of an electric motor between the two contact ends of the wire conductor forms at least one first U-shaped arc which has two substantially parallel limbs connected to one another by a vertex. In accordance with this preferred embodiment of the invention, by means of said first U-shaped arc, the interference suppression coil is fixed to the brushholder plate, in particular by a joining connection, such that it is only necessary to ensure the fixing of at least one U-shaped arc, fashioned in particular in a manner projecting from the interference suppression coil in a leg-like manner, to the brushholder plate, said arc having a correspondingly sufficient inherent stability for this purpose.
A further advantageous configuration of the invention is characterized in that the two parallel limbs of at least the first U-shaped arc are arranged
substantially in a plane along the longitudinal central axis, wherein the two parallel limbs, that is to say the first and second limbs, can preferably bear against one another in a frictionally locking manner, as a result of which the strength and the stiffness of the U-shaped arc are additionally reinforced as well. In a further aspect of the invention, the two parallel limbs of a first U-shaped arc at least in the end region of the at least one turn are arranged
substantially in a plane transversely, in particular perpendicularly, with respect to the longitudinal central axis of the interference suppression coil, wherein in this case, too, the two parallel limbs, that is to say the first and second limbs, can bear against one another in a frictionally locking manner, as a result of which the strength and the stiffness of the U-shaped arc are likewise additionally reinforced as well.
In the case of a further configuration of the electric motor according to the invention, the two parallel limbs of a U-shaped arc at least in the end region of the at least one turn are arranged substantially in a plane parallel to the longitudinal central axis, preferably at a shortest distance from the longitudinal central axis, which corresponds to the radius of a turn closest to said
U-shaped arc, thus resulting in a particularly simple geometry and a low bending complexity for producing the interference suppression coil.
It is particularly preferred if the interference suppression coil is fashioned in such a way that turns of the interference suppression coil are formed substantially between the first and a further, second U-shaped arc which is configured substantially like the first U-shaped arc. This arrangement of U-shaped arcs substantially at the two outer turns of the interference suppression coil results in a particularly high stability of the interference suppression coil during the operation of the electric motor.
In one further development of the invention, a ferrite core is introduced between the turns of the interference suppression coil and is secured against falling out and preferably axially fixed along the longitudinal central axis of the interference suppression coil. This can be effected, in particular, by virtue of the fact that a limb of at least one of the two U-shaped arcs, the second electrical contact end and/or at least one section of the wire conductor of a U-shaped arc, which section is integrally formed on one of the limbs, are/is shaped in such a way that the opening cross sections of the turns of the interference suppression coil that are arranged in each case in front of and behind the ferrite core are closed or at least covered, such that the ferrite core can bear against the latter and cannot slide from the turns surrounding it. In one particularly preferred embodiment of the electric motor according to the invention, at least one U-shaped arc projects from a first side of the brushholder plate through a first perforation in the brushholder plate to the opposite side of the brushholder plate relative to the first side of the brushholder plate, such that the interference suppression coil is fixable to the brushholder plate by means of this U-shaped arc by the joining connection.
In a further particularly preferred embodiment, the interference suppression coil is fixed to the brushholder plate in a clamped manner, wherein turns of the interference suppression coil substantially bear against the brushholder plate, such that they bear against the surface of the brushholder plate in a frictionally locking manner and no bending moments can act on the fixing of the interference suppression coil if the electric motor is caused to oscillate or vibrate. It could also be stated that the at least one turn of the interference suppression coil and the reshaped region - forming the at least one joining location - of the wire conductor are arranged on different sides of the brushholder plate and touch the brushholder plate there preferably directly in each case.
In addition, for reducing the outlay on parts for the fixing of the interference suppression coil, it is also possible for the U-shaped arc to be reshaped at the opposite side of the brushholder plate relative to the at least one turn, preferably by virtue of the two parallel limbs of said arc being bent in sections substantially perpendicularly or parallel to the longitudinal central axis of the interference suppression coil.
In a further preferred aspect of the invention, the first electrical contact end of the wire conductor, for connection to the power supply connection, has a connection section likewise consisting of an electrical conductor. Said connection section is led, in particular pressed, through a further, second perforation in the brushholder plate and on the opposite side of the
brushholder plate is connected to the power supply connection, which is embodied in particular as an electrical connection terminal, preferably by clamping, soldering or welding.
In a further embodiment, no further, second perforation is comprised and the first electrical contact end is led together with a U-shaped arc through a first perforation to the opposite side of the brushholder plate and connected to the power supply connection, wherein the shape of two U-shaped arcs connected to one another via a respective limb, that is to say with an S-shape, arises in this case. The limbs thereof preferably in turn bear against one another, thus resulting in a frictionally locking engagement of the individual limbs and hence a further stiffening or reinforcement of the fixing of the interference
suppression coil.
A further advantageous configuration of the invention is distinguished by the fact that the first electrical contact end of the wire conductor is longer than the second electrical contact end and is preferably longer than the longitudinal extent of the interference suppression coil in the wound state. The longer contact end can be introduced as a conductor formed integrally with the interference suppression coil, for example, into a preferably further connection terminal housing connected to the brushholder plate.
In this respect, the invention also affords the advantage that solid contact terminals used previously for interconnection between the electrical connection terminals and the first electrical contact ends of the brush can be omitted and a direct connection between the connection terminal and the first electrical contact end can be produced by an electrical conductor which preferably consists of the same material as the wire conductor of the interference suppression coil or is shaped from the wire conductor of the interference suppression coil. A method for producing or assembling an electric motor according to the invention can comprise the following steps:
- bending at least one turn of at least one interference suppression coil around a longitudinal central axis from a wire conductor, wherein the wire conductor has a first electrical contact end for connection to a power supply connection of the electric motor and a second electrical contact end for connection to a conductor connected to the brush, such as a braided conductor or a stranded conductor,
- fixing the at least one interference suppression coil by means of a
joining connection directly to the brushholder plate by producing the joining connection.
In this case, the last-mentioned step of producing the joining connection can preferably comprise the following steps:
- positioning and threading at least one part of the wire conductor,
preferably a U-shaped arc, into a corresponding perforation in the brushholder plate,
- joining the led-through part of the wire conductor with the brushholder plate by permanent reshaping of it at the joining location.
The further features and advantages are also evident from the following description of exemplary embodiments in association with the accompanying figures.
In the figures:
Figure 1 shows a first embodiment of a brushholder plate of an electric motor according to the invention with two brushes and two interference suppression coils;
Figures 1 a and 1 b show a front view and a side view of a first embodiment of an interference suppression coil before assembly; Figures 1 c to 1 e show a front view, a side view and a perspective view of the interference suppression coil according to Figures 1 a and 1 b after assembly;
Figure 2 shows an exploded view of the brushholder plate according to Figure 1 ;
Figure 3 shows a rear side view of the brushholder plate according to Figure 1 ;
Figure 4 shows a cross-sectional view along the section A-A through the brushholder plate according to Figure 3;
Figure 5 shows a second embodiment of a brushholder plate of an electric motor according to the invention with two brushes and two interference suppression coils;
Figure 6 shows a perspective view of the brushholder plate
according to Figure 5;
Figure 7 shows a plan view of a brushholder plate according to
Figure 5;
Figure 8 shows an exploded view of the brushholder plate according to Figures 5 to 7;
Figures 9a and 9b show a front view and a side view of a second
embodiment of an interference suppression coil before assembly; Figures 9c to 9e show a front view, a side view and a perspective view of the interference suppression coil according to Figures 9a and 9b after assembly;
Figures 10a and 10b show a front view and a side view of a third embodiment of an interference suppression coil before assembly;
Figures 10c to 10e show a front view, a side view and a perspective view of the interference suppression coil according to Figures 10a and 10b after assembly.
Figures 1 to 4 show a first embodiment of the invention on the basis of a preassembled brushholder plate 1 for incorporation into an electric motor according to the invention, said electric motor not being shown in the figures.
Said brushholder plate 1 is preferably accommodated and retained in a clamped manner between a gear mechanism housing and a motor housing (neither of which is shown in the figures). For positioning in the gear mechanism housing, the brushholder plate 1 has a lug 18. Further lugs are shown in Figure 1 , and are not provided with reference signs for reasons of clarity.
Figure 1 shows a brushholder plate 1 configured in a ring-like fashion, wherein this shape can substantially correspond to the shape of the gear mechanism housing in which the brushholder plate is accommodated. For the purposes of the invention, however, a brushholder plate can have any arbitrary shape and configuration and is preferably composed of an
electrically insulating substance, in particular hard paper. In particular, the brushholder plate is not necessarily shaped in a planar or flat fashion, but rather can also be curved, angular and/or bent and also consist of one or a plurality of parts connected to one another. In the assembled state of the electric motor according to the invention, it is provided that the current transformer (not shown) of the electric motor extends through the round cutout 17 of the brushholder plate 1 , such that the brushes 2 and 2' fixed to the brushholder plate 1 , said brushes each being introduced in a casing 12 and 12', slide on the periphery of the current transformer.
The embodiment of a brushholder plate 1 for an electric motor according to the invention in accordance with Figure 1 furthermore shows two interference suppression coils 3 and 3' fixed to the brushholder plate 1 , said interference suppression coils each consisting of a wire conductor 3a and 3a' having a multiplicity of turns 3b and 3b' which are wound in each case around the longitudinal central axes A of the interference suppression coils.
In accordance with Figure 1 , the wire conductors 3a and 3a' of the
interference suppression coils 3 and 3' have first electrical contact ends 3c and 3c', which (in accordance with Figure 2) are connected to contact bridges 13 and 13', which are led through an elongate perforation in the brushholder plate 1 and are electrically connected to a power supply connection 4 and 4' of the electric motor, that is arranged on the rear side of the brushholder plate 1 .
Furthermore, the wire conductors 3a and 3a' in accordance with Figure 1 have a second electrical contact end 3d and 3d' for connection to a conductor connected to the brush 2 and 2', in particular a braided conductor or a stranded conductor.
The interference suppression coils 3 and 3' shown in Figure 1 respectively form between the two contact ends 3c and 3d and 3c' and 3d' a first and a second U-shaped arc 5 and 6 and 5' and 6' (not shown in Figure 1 ), by means of which the inference suppression coils 3 and 3' are fixed to the brushholder plate 1 . Figures 1 a and 1 b in this respect show in detail the interference suppression coil 3 in the first embodiment of the invention according to Figures 1 to 4 in a non-assembled state.
In accordance with Figure 1 a, two U-shaped arcs 5 and 6 are formed on the non-assembled interference suppression coil 3, said U-shaped arcs each having two substantially straight, parallel limbs 5a and 5b and 6a and 6b connected to one another respectively by a vertex 5c and 6c.
In accordance with Figure 1 b, it is furthermore clearly discernible that the respective two parallel limbs 5a and 5b of the first U-shaped arc 5 and the respective two parallel limbs 6a and 6b of the second U-shaped arc 6 in the non-assembled state are arranged substantially in a plane along the longitudinal central axis A of the interference suppression coil 3.
According to the invention, however, an interference suppression coil can also form in each case only a single U-shaped arc, by means of which the interference suppression coil is at least partly fixed to the brushholder plate 1 .
What is common to all the embodiments illustrated in the figures in their entirety is that the U-shaped regions which are adjacent in the axial direction of the interference suppression coil and which later form the joining location of the joining connection are always directly adjacent to the turns of the interference suppression coil. Furthermore, in the case of the embodiments illustrated, twisting, lock-forming, widening, punching, notching, winding or split-pin fixing of the end regions of the U-shaped arcs that project beyond the brushholder plate after threading-in would be conceivable instead of bending-over, in order to produce the joining connection according to the invention.
Furthermore, according to the invention, a U-shaped arc can be fixed to a brushholder plate by means of a joining connection of any type, in particular including by fixing in a mount, reshaping, bending, clamping, pressing, adhesive bonding, soldering and welding. Figure 2 shows the brushholder plate 1 in accordance with Figures 1 to 4 in an exploded drawing. The two U-shaped arcs 5 and 6 of the interference suppression coil 3, for the assembly thereof, are to be led from the front side, that is to say a first side 9a, of the brushholder plate 1 through first perforations 8 and 8' in the brushholder plate 1 to the opposite side 9b of the brushholder plate 1 relative to the first side 9a of the brushholder 1 , such that the ends of both U-shaped arcs 5 and 6 on the rear side at the brushholder plate 1 project from the leadthroughs 8 and 8', where the interference suppression coil 3 is fixable to the brushholder plate 1 by means of said U-shaped arcs 5 and 6. Once again, any types of joining connections can be used for this purpose.
Furthermore, Figure 2 reveals one particularly preferred further development of a fixing on the basis of the interference suppression coil 3', which is fixable to the brushholder plate 1 in a clamped manner by means of the U-shaped arcs 5' and 6' by virtue of the U-shaped arcs 5' and 6' being reshaped at the opposite side 9b of the brushholder plate 1 , specifically by virtue of the fact that the two parallel limbs are to be bent over in sections substantially perpendicularly to the longitudinal central axis A of the interference
suppression coil 3'. Figure 2 correspondingly shows the interference suppression coil already in the assembled form, that is to say with bent ends of the two U-shaped arcs 5' and 6'.
Furthermore, Figure 2 shows a preferred connection terminal housing, which is connectable or connected to the brushholder plate and which
accommodates contact bridges 13 and 13' and the electrical connection terminals 4 and 4' and is furthermore preferably embodied as an insulation housing. The contact bridges 13, 13' and the connection terminals 4, 4' are provided separately here and are produced for example from a sheet-metal section by a stamping and bending process.
Figure 1 c shows an interference suppression coil 3 in which the ends of the two U-shaped arcs 5 and 6 and the vertices 5c and 6c thereof of the interference suppression coil 3 in the assembled state of the interference suppression coil 3 or the electric motor are likewise angled, that is to say shaped in a manner bent perpendicularly to the longitudinal central axis A.
The bending course of the U-shaped arcs 5 and 6 in the assembled state of the interference suppression coil or the electric motor is readily discernible with reference to Figures 1 d and 1 e. Accordingly, the ends of the two parallel limbs 5a and 5b of the first U-shaped arc 5 and the ends of the two parallel limbs 6a and 6b of the second U-shaped arc 6 in the assembled state are aligned substantially in a plane parallel to the longitudinal central axis A.
Figure 3 shows a rear side view 9b of the brushholder plate 1 according to Figure 1 , on which the interference suppression coils 3 and 3' are mounted by the U-shaped arcs being inserted into the correspondingly embodied perforations, wherein only the ends - bent transversely with respect to the longitudinal central axis A in accordance with Figures 1 c to 1 e - of the first U-shaped arc 5 and 6 of the first interference suppression coil 3 and of the second U-shaped arc 5' and 6' of the second interference suppression coil 3' are visible.
Figure 4 shows a cross section A-A through the brushholder plate 1 according to the arrows A-A from Figure 3. The free end of the second U-shaped arc 6 is bent on the rear side 9b of the brushholder plate transversely with respect to the longitudinal central axis A of the interference suppression coil 3.
Furthermore, Figure 4 shows that the interference suppression coil 3 is fixed to the brushholder plate in a clamped manner, wherein turns 3b of the interference suppression coil 3 substantially bear directly against the brushholder plate 1 , such that they bear against the surface of the
brushholder plate 1 in a frictionally locking manner, for example, as a result of which lever force moments on the interference suppression coil 3 are reduced. For further improvement of the fixing, the interference suppression coil 3 can also be fixed to the brushholder plate 1 in a pretensionned manner. In the context of the invention, it is also possible to fix an interference suppression coil to the brushholder plate without a clamping or a
pretensioning and/or, instead of a bending, to reshape the free end of a U-shaped arc in particular by crimping or pressing, or to fix it at the rear side using an arbitrary fixing means, for example using a pin introduced into an opening of the U-shaped arc, in such a way that the end of the U-shaped arc is secured against sliding out of the perforation in the brushholder plate.
Figures 5 to 8 show the further development of a brushholder plate 1 with two interference suppression coils 3 and 3' fixed thereto of an electric motor according to the invention.
The two interference suppression coils 3 and 3', apart from the first electrical contact ends 3c and 3c', are embodied in a manner corresponding to the interference suppression coils according to Figures 1 to 4 and are accordingly also fixed to the brushholder plate 1 in the circumferential direction radially within the inner and the outer edge of the brushholder plate.
In contrast to Figures 1 to 4, the interference suppression coils 3 and 3' in accordance with Figures 5 to 8 have first electrical contact ends 3c and 3c' which are not connected to contact bridges, but rather are embodied as connection sections 15 and 15'. The latter are preferably shaped from the same material as the wire conductor 3a or 3a' and/or from the wire conductor of the interference suppression coils 3 and 3', in particular integrally therewith, and are led through a second perforation 10 and 10' in the brushholder plate 1 . On the rear side of the brushholder plate 1 , said connection sections 15 and 15' are electrically and preferably mechanically connected to the power supply connections 4 and 4' of the electric motor.
In this case, Figure 6 shows the two connection sections 15 and 15' arranged at the first electrical contact ends 3c and 3c', said connection sections being led through the second perforations 10 and 10' in the brushholder plate 1 and being fixed to the two power supply connections 4 and 4' embodied as connection terminals, wherein Figure 6 shows one preferred embodiment without a connection terminal housing for accommodating the connection sections 15 and 15'. In principle, the second perforations could also be dispensed with.
In contrast thereto, Figures 7 and 8 show an embodiment with a connection terminal housing 14, which is designed for accommodating the connection sections 15 and 15' embodied integrally with the interference suppression coil 3, capacitors 1 1 and 1 1 ', and also for accommodating the connection terminals 4 and 4' which are to be connected to the connection sections 15 and 15' preferably by clamping, soldering or welding. In accordance with Figure 7, for this purpose provision is made of an access for a tool, e.g. for a welding tool, through an access opening 19, 19' in the underside of the connection terminal housing 14.
Figures 9a and 9b show a second embodiment of an interference suppression coil 3 according to the invention in a non-assembled state, that is to say a state not reshaped with regard to the production of the joining connection. In accordance with Figure 9a, two U-shaped arcs 5 and 6 are formed on said non-assembled interference suppression coil 3, said U-shaped arcs each having two substantially straight, parallel limbs 5a and 5b and 6a and 6b connected to one another respectively by a vertex 5c and 6c, preferably integrally. In accordance with Figure 9b, it is furthermore discernible that the respective two parallel limbs 5a and 5b of the first U-shaped arc 5 and the respective two parallel limbs 6a and 6b of the second U-shaped arc 6 in the non-assembled state are arranged substantially in a plane transversely with respect to the longitudinal central axis A of the interference suppression coil 3.
The bending course of the U-shaped arcs in the assembled state of the interference suppression coil 3 or the electric motor is readily discernible with reference to Figures 9c to 9e. Accordingly, the free ends of the two U-shaped arcs 5 and 6 and the vertices 5c and 6c thereof of the interference
suppression coil 3 in the assembled state are aligned substantially in a plane parallel to the longitudinal central axis A. Figures 10a and 10b show in detail a second embodiment of an interference suppression coil 3 according to the invention in a non-assembled state. In accordance with Figure 10a, two U-shaped arcs 5 and 6 are formed on the non-assembled interference suppression coil 3 in the end region on both sides of the turns of the interference suppression coil 3, said U-shaped arcs once again each having two substantially straight, parallel limbs 5a and 5b and 6a and 6b connected to one another respectively by a vertex 5c and 6c. In accordance with Figure 10b, it is furthermore discernible that the respective two parallel limbs 5a and 5b of the first U-shaped arc 5 and the respective two parallel limbs 6a and 6b of the second U-shaped arc 6 in the non-assembled state are arranged substantially in a plane parallel to the longitudinal central axis A of the interference suppression coil 3, wherein the shortest, that is to say the horizontal, distance from the longitudinal central axis A corresponds to the radius of the turns 3b. The two U-shaped arcs 5, 6 follow the winding direction of the turns and are thus arranged preferably parallel in the figures on different sides relative to a central plane, between the planes spanned by the individual U-shaped arcs 5, 6.
The bending course of the U-shaped arcs in the assembled state of the interference suppression coil 3 or the electric motor is readily discernible with reference to Figures 10c to 10e. Accordingly, the ends of the two U-shaped arcs 5 and 6 and the vertices 5c and 6c thereof of the interference
suppression coil 3 in the assembled state are aligned substantially in a plane perpendicular to the longitudinal central axis A, to be precise towards one another, thus resulting in the possibility of an improved, braced fixing of an interference suppression coil to the brushholder plate.
Figures 1 e, 9e and 10e furthermore show one preferred further development of the invention in which a ferrite core 16 is introduced between the turns 3b of the interference suppression coil 3 and is axially fixed along the longitudinal central axis A. This is carried out, in accordance with Figures 1 e and 9e, by virtue of the fact that the limbs of the two U-shaped arcs 5 and 6 are shaped in such a way that the opening cross sections of the turns of the interference suppression coil 3 that are arranged in each case in front of and behind the ferrite core are covered, such that the ferrite core 16 can bear against the latter and cannot slide from the turns 3b surrounding it. For this purpose, the turn which is in each case directly adjacent to the U-shaped arc 5, 6 is embodied as a partial turn, e.g. as a half turn, relative to a full turn, and runs substantially in the radial direction of the turn as seen substantially in the viewing direction of the longitudinal central axis A.
In accordance with Figure 10e, the ferrite core 16 is axially fixed by virtue of the fact that an integrally formed section 7 of the wire conductor 3a is in each case fitted to the limbs 5b and 6a of the U-shaped arcs 5 and 6 and shaped in such a way that the opening cross sections of the turns of the interference suppression coil 3 that are arranged in each case in front of and behind the ferrite core are covered, such that the ferrite core 16 likewise bears against the latter and cannot slide from the turns 3b surrounding it.
The invention advantageously enables improved, in particular simplified, assembly and ensures an increased reliability during the assembly process. During assembly it is particularly advantageous if a brushholder plate 1 is preassembled by at least one of the above embodiments of an interference suppression coil 3 being fixed thereto.
For this purpose, preferably, in a first step, one or a plurality of U-shaped arcs 5 and 6 of the interference suppression coil 3 to be fixed are introduced, in particular plugged or press-fitted, from a first side 9a of a brushholder plate 1 at least in sections into perforations 8 and 8' of the brushholder plate 1 , such that preferably the turns of the interference suppression coil 3 can bear at least partly against the surface of the brushholder plate 1 and/or the
interference suppression coil 3 bears against the latter in a pretensioned manner. Afterwards, in a further step, at the opposite side 9b, that is to say at the rear side of the brushholder plate 1 , the ends of the U-shaped arcs 5 and 6 are to be fixed with a joining connection, in particular by the free ends of the
U-shaped arcs 5 and 6 being reshaped and/or bent in sections. In an optional step supplementary or additional to the above steps, at the first contact end 3c of the interference suppression coil 3, a connection section 10 of a conductor is fitted and/or is to be led through a second perforation 10 to the rear side 9b of the brushholder plate 1 and is to be fixed to a connection terminal, preferably by welding, soldering or clamping.
List of Reference Signs
1 Brushholder plate
2, 2' Brush
3, 3' Interference suppression coil
3a, 3a' Wire conductor
3b, 3b' Turn
3c, 3c' First electrical contact end of the interference suppression coil
3d, 3d' Second electrical contact end of the interference
suppression coil
4, 4' Power supply connection, connection terminal
5, 5' First U-shaped arc
6, 6' Second U-shaped arc
5a First limb of the first U-shaped arc
5b Second limb of the first U-shaped arc
5c Vertex of the first U-shaped arc
6a First limb of the second U-shaped arc
6b Second limb of the second U-shaped arc
6c Vertex of the second U-shaped arc
7 Section of the wire conductor
8, 8', 8", 8"' First perforation in the brushholder plate
9a First side of the brushholder plate
9b Opposite side of the brushholder plate
10, 10" Second perforation in the brushholder plate
1 1 , 1 1 ' Capacitor
12, 12' Casing for brush
13, 13' Contact bridge
14 Connection terminal housing
15, 15' Connection section of the wire conductor
16 Ferrite core
17 Cutout for current transformer
18 Lug
19, 19' Access opening 20 Assembly aid
A Longitudinal central axis

Claims

Claims
1 . Electric motor, preferably for a vehicle windscreen wiper with a gear mechanism fitted thereto, comprising a housing for the electric motor and/or the gear mechanism and a brushholder plate (1 ), which is accommodated by the housing and to which are fixed at least one brush (2, 2') for the power supply of the electric motor and at least one interference suppression coil (3, 3') comprising a wire conductor (3a, 3a') having at least one turn (3b, 3b') about a longitudinal central axis (A), wherein the wire conductor has a first electrical contact end (3c, 3c') for connection to a power supply connection (4, 4') of the electric motor and a second electrical contact end (3d, 3d') for connection to a conductor connected to the brush (2, 2'), such as a braided conductor or a stranded conductor, characterized in that the interference suppression coil (3, 3') is fixed directly to the brushholder plate (1 ) by means of a joining connection.
2. Electric motor according to Claim 1 , characterized in that the joining connection is embodied as a force-locking and/or positively locking
connection.
3. Electric motor according to Claim 1 or 2, characterized in that the wire conductor (3a, 3a') is embodied in such a way that the joining connection is obtainable by permanent reshaping of the wire conductor (3a, 3a').
4. Electric motor according to any of the preceding claims, characterized in that the joining connection comprises at least one joining location at which the interference suppression coil (3, 3') between the two contact ends (3c, 3d, 3c', 3d') of the wire conductor (3) is led through a perforation (8, 8', 10, 10') in the brushholder plate (1 ) and is joined to the brushholder plate (1 ) by reshaping of the wire conductor (3) in the region of the joining location at said brushholder plate (1 ).
5. Electric motor according to any of the preceding claims, characterized in that the interference suppression coil (3, 3') between the two contact ends (3c, 3d, 3c', 3d') of the wire conductor (3) forms at least one first U-shaped arc (5, 5') which has two substantially parallel limbs (5a, 5b) connected to one another by a vertex (5c, 5c') and by means of which the interference suppression coil (3, 3') is fixed to the brushholder plate (1 ) by the joining connection.
6. Electric motor according to any of the preceding claims, wherein the two parallel limbs (5a, 5b) of the first U-shaped arc (5, 5') at least in the end region of the at least one turn (3b, 3b') are arranged substantially in a plane through the longitudinal central axis (A) or a plane running parallel thereto.
7. Electric motor according to any of the preceding claims, wherein the two parallel limbs (5a, 5b) of the first U-shaped arc (5, 5') at least in the end region of the at least one turn (3b, 3b') are arranged substantially in a plane transversely, in particular perpendicularly, with respect to the longitudinal central axis (A).
8. Electric motor according to any of the preceding claims, wherein the two parallel limbs (5a, 5b) of the first U-shaped arc (5, 5') are arranged substantially in a plane parallel to the longitudinal central axis (A), preferably at a distance from the longitudinal central axis (A) which corresponds to the radius of a turn (3b) closest to said U-shaped arc (5, 5').
9. Electric motor according to any of the preceding claims, wherein the interference suppression coil (3, 3') is fashioned in such a way that turns (3b) of the interference suppression coil (3, 3') are formed substantially between the first and a further, second U-shaped arc (6, 6'), which is configured substantially like the first U-shaped arc (5, 5').
10. Electric motor according to Claim 5, wherein the limbs (5a, 5b, 6a, 6b) of the two U-shaped arcs (5, 5', 6, 6') and/or at least one section (7) of the wire conductor (3) that is integrally formed on one of the limbs (5a, 5b, 6a, 6b) and/or the second electrical contact end (3d, 3d') are/is shaped in such a way that a ferrite core (16) introduced between the turns (3b) of the interference suppression coil (3, 3') is secured against falling out and is preferably axially fixed along the longitudinal central axis (A).
1 1 . Electric motor according to any of the preceding claims, wherein at least one U-shaped arc (5, 5', 6, 6') projects from a first side (9a) of the brushholder plate (1 ) through a first perforation (8, 8') in the brushholder plate (1 ) to the opposite side (9b) of the brushholder plate (1 ) relative to the first side (9a) of the brushholder plate (1 ) and the interference suppression coil (3, 3') is fixed to the brushholder plate (1 ) by reshaping of the U-shaped arc (5, 5', 6, 6').
12. Electric motor according to Claim 7, wherein turns (3b, 3b') of the interference suppression coil (3, 3') bear substantially directly against the brushholder plate (1 ).
13. Electric motor according to Claim 8, wherein the U-shaped arc (5, 5', 6, 6') in the assembled state of the electric motor is reshaped at the opposite side of the brushholder plate (1 ), preferably by virtue of the two parallel limbs (5a, 5b, 6a, 6b) of said arc (5, 5', 6, 6') being bent in sections substantially perpendicularly or parallel to the longitudinal central axis (A) of the
interference suppression coil (3, 3') and preferably bearing directly against that side of the brushholder plate (1 ) which faces away from the at least one turn (3b, 3b').
14. Electric motor according to any of the preceding claims, wherein the first electrical contact end (3c, 3c') of the wire conductor, for connection to the power supply connection (4), has a connection section (15, 15') which is led through a further, second perforation (10, 10') in the brushholder plate (1 ) and on the opposite side (9b) of the brushholder plate (1 ) is connected to the power supply connection (4, 4'), which is embodied in particular as an electrical connection terminal, preferably by clamping, soldering or welding.
15. Electric motor according to any of the preceding claims, characterized in that the first electrical contact end (3c, 3c') of the wire conductor is longer than 'the second electrical contact end (3d, 3d') and is preferably longer than the longitudinal extent of the interference suppression coil (3, 3') in the wound state.
PCT/EP2015/067225 2014-09-24 2015-07-28 Electric motor, preferably for a vehicle windscreen wiper WO2016045827A1 (en)

Applications Claiming Priority (2)

Application Number Priority Date Filing Date Title
DE102014113858.9A DE102014113858A1 (en) 2014-09-24 2014-09-24 Electric motor, preferably for a vehicle windshield wiper
DE102014113858.9 2014-09-24

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Publication number Priority date Publication date Assignee Title
DE102014118430A1 (en) 2014-12-11 2016-06-16 Endress + Hauser Gmbh + Co. Kg Active brazing material and method for active brazing of components

Citations (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
EP0712195A2 (en) * 1994-11-12 1996-05-15 AEG KLEINMOTOREN GmbH Electric motor drive for a unit axially plonge mounted on the motor housing
US20020140301A1 (en) * 2000-08-23 2002-10-03 Siemens Automotive Inc. RFI suppression chokes with integral attachment features and extension legs to replace bus bars
GB2495713A (en) * 2011-10-17 2013-04-24 Nidec Motors & Actuators Gmbh Germany DC brush motor for driving a cooling system fan

Family Cites Families (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
DE3112471A1 (en) * 1981-03-28 1982-10-07 Robert Bosch Gmbh, 7000 Stuttgart "SMALL ELECTRIC MOTOR WITH A COLLECTOR AND COOPERATING BRUSHES THAT WORK WITH THIS"
US6812605B2 (en) * 2002-10-01 2004-11-02 Siemens Vdo Automotive Inc. Self-retained RFI suppression choke for electric motor

Patent Citations (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
EP0712195A2 (en) * 1994-11-12 1996-05-15 AEG KLEINMOTOREN GmbH Electric motor drive for a unit axially plonge mounted on the motor housing
US20020140301A1 (en) * 2000-08-23 2002-10-03 Siemens Automotive Inc. RFI suppression chokes with integral attachment features and extension legs to replace bus bars
GB2495713A (en) * 2011-10-17 2013-04-24 Nidec Motors & Actuators Gmbh Germany DC brush motor for driving a cooling system fan

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