DE102014104199A1 - Rotor pole configuration of rotating electrical machine - Google Patents

Abstract

A rotor (56 ') for a rotating electrical machine (20') is described, the rotor (56 ') having a first pole piece (44') and a second pole piece (48 '), each of which has a magnetic hub (92, 96) arranged for rotation about an axis (60) with the first and second pole piece hubs (44 ', 48') spaced from one another along the axis (60). A plurality of magnetic first and second pole fingers (100 ', 104') are spaced apart and extend between the first and second pole piece hubs (92, 96). Each pole finger (100 ', 104') has a proximal end (148 ') attached to the associated hub (92, 96) and an axially opposite distal end (152'). The first and the second pole fingers (100 ', 104') alternate in the circumferential direction around the axis (6). Each pole finger (100 ', 104') has a radially inner surface (184 ', 192') defining a cavity which extends axially from the distal end (152 ') to one end of the cavity. For each pole finger (100 ', 104') the radial distance between the axis (60) and the radially inner surface (184 ', 192') is at an axial location between the distal end (152 ') and the end of the cavity ( 224) much larger inside the cavity than outside the cavity.

Description

PRIORITY CLAIM FOR ASSOCIATED APPLICATIONS

The present application claims priority from the following patent applications: US Provisional Patent Application No. 61 / 808,991 entitled Rotor Pole Configuration of Rotary Electric Machine filed on Apr. 5, 2013; and US Patent Application No. 14 / 085,241 titled Rotor Pole Configuration of Rotary Electrical Machine filed Nov. 20, 2013. , 2013.

BACKGROUND

The present disclosure relates to rotating electrical machines, in particular rotors therefor, more particularly rotor types containing permanent magnets.

An example of a known rotary electric machine to which the teaching of the present disclosure can be applied, namely, a generator for use in a vehicle, is shown in FIG 1 shown. The generator 20 has a housing 24 and a wave 28 in the case 24 with front and rear rotary element bearings 32 and 36 is stored. A belt driven pulley 40 is at a protruding front end of the shaft 28 attached. The rotor 56 the illustrated rotating electric machine 20 has front and rear generator poles 44 and 48 on that on the shaft 28 are mounted and rotate with this. The generator 20 generally has a stator 52 on, the rotor 56 surrounds and on the housing 24 is attached. Rotation of the rotor 56 around its axis of rotation, the central axis 60 The machine causes that in the stator winding 68 an alternating current is induced.

The stator 52 usually contains a stator core 64 around which the stator winding 68 is wound. As is known in the art, the stator core 64 usually a sheet stack 72 on, which is formed of a plurality of sheets, in the axial direction with respect to the axis of rotation 60 the wave 28 are stacked. Each sheet can be made of electrical steel or other electrical ferromagnetic material. As 2 shows contains the stator winding 68 usually several conductors 76 and the stator core 64 defines several slots 80 between them several stator teeth 84 form. The stator slots 80 and teeth 84 are also in 10 shown. The ladder 76 extend axially through the slots 80 and are conventionally wound such that the turns around the circumference of the stator 52 are wound. As 2 shows are the Statorwicklungsleiter 76 a first leader 76a , a second leader 76b and a third conductor 76c , These conductors define 3 phases of the electrical current generated by the generator.

The rotor 56 is a type known as a claw pole rotor and a pair of opposing claw pole pieces 44 . 48 and a field coil 88 around a central axis 60 is arranged around. The pole pieces 44 and 48 are made of a magnetic material such as steel, are substantially identical, have each hub sections 92 . 96 and a plurality of respective elongated pole segments or fingers 100 . 104 , The pole fingers of each pole piece 44 . 48 are around the circumference of the respective hub section 92 . 96 distributed and through cavities 108 separated in the respective hub portion. The Polfinger 100 . 104 from every pole piece 44 . 48 extend axially away from their respective hub portion and axially toward the hub portion 92 . 96 , the other pole piece. In addition, the Polfinger 100 . 104 from every pole piece 44 . 48 symmetrically along the circumference of the respective hub portion 92 . 96 arranged and gripping - with the rotor built up as on the shaft 28 arranged - in a non-contact, spaced-holding arrangement each with the Polfingern of the other pole piece into each other, as in 2 shown. Air gaps or channels thus become between adjacent pole fingers 100 . 104 defined and are circumferentially around the rotor 56 distributed.

As 3 shows is the exciter field coil 88 of the rotor 56 on an electrically insulating bobbin 112 wound. The sink 88 and the bobbin 112 are between the pair of axially opposed inwardly facing surfaces 116 and 120 the pole piece hub sections 92 . 96 arranged. pole pieces 44 . 48 can sections 121 have, which extend axially and around which the field coil 88 and her bobbin 112 are arranged around, as in 1 shown, or the field coil 88 and her bobbin 112 can around a cylindrical rotor core member 122 disposed about the central axis 60 between the pole pieces 44 . 48 is arranged as in 3 shown. According to 1 becomes excitation DC through the excitation winding 88 over a pair of slip rings 124 and associated contact brushes 128 directed. The slip rings 124 are at the shaft 28 attached and coupled during operation, the field coil 88 over the contact brushes 128 to a regulated DC voltage source. A control system, referred to as a voltage regulator (not shown), is used to apply a DC voltage of appropriate magnitude to the excitation winding 88 to apply.

The pole pieces 44 . 48 and the energized field winding 88 generate a magnetic field of alternating polarity, which coincides with the rotor 56 around the central axis 60 rotates. Although an exciting DC in the field winding 88 is passed, the interweaving creates the alternating pole fingers 100 . 104 an alternating coupling with the magnetic flux. This coupling with the magnetic flux is through the winding conductors 76 of the stationary stator 52 generates the rotor 56 surrounds. The movement of the alternating coupling of the magnetic flux passing through the rotor 56 over the stator winding conductors 76a . 76b . 76c takes place, generates in a known manner a three-phase alternating current.

The usual way is the generator 20 generated alternating current in a rectifier 132 fed to the back of the case 24 can be arranged as in 1 shown. The generator may additionally include filters and voltage conditioning devices through which the generated electrical voltage is conducted before being fed as a DC electrical voltage into the positive terminal of the vehicle battery (not shown) or an electric distribution bus (not shown). The desired RMS value of the generator 20 AC voltage generated depends on the magnitude of the DC voltage applied by the voltage regulator to the excitation winding 88 is created. In addition, front and rear circulating air fans are 136 and 140 Opposite on the axially outward sides of the pole pieces 44 . 48 arranged. The fans 136 . 140 are to the rotor 56 coupled and rotate together with this. A cooling airflow is provided by the fans 136 . 140 Usually pulled axially inwards into the housing and ejected radially outwardly from the housing. The rear fan 140 usually directs a cooling air flow through the rectifier 132 and other electrical components of the generator 20 , If an airflow path is provided, the fans can 136 . 140 also part of the cooling air flow around the Polfinger 100 . 104 and the exciter coil 88 conduct.

The direction of rotation of the rotor 56 relative to the stator 52 and thus the direction of rotation of Rotorpolfinger 100 . 104 relative to the stator teeth 84 is by the arrow 144 shown. When the field coil is energized 88 with regulated direct current becomes the rotor 56 magnetized, with adjacent pole fingers 100 . 104 alternate in the circumferential direction between north (N) and south (S) of magnetic polarity. In other words, all Polfinger have 100 magnetic polarity N and all pole fingers 104 magnetic polarity S. It can therefore be seen that when the rotor rotates 56 the alternating magnetic polarities of the pole fingers 100 . 104 one behind the other around the stator 52 revolve and thereby an output current in the stator winding 68 induce. Those skilled in the art will recognize that the respective magnetic polarities N and S of the front and rear pole pieces 44 . 48 are determined as a function of the selected direction of the DC current passing through the field coil 88 flows.

The 5A to 5H show an example of a known Klauenpolstücks 44 or 48 with several pole fingers or segments 100 . 104 each having a base or a proximal end 148 have that to the corresponding pole piece hub section 92 . 26 in places between the cavities 108 are connected. Every Polfinger 100 . 104 also has a tip or distal end 152 that of the corresponding base 148 is opposite. The tips 152 the Polfinger 100 . 104 one pole piece 44 . 48 are near the base 148 of the pole finger 100 . 104 the other pole piece 44 . 48 arranged as in 3 shown.

Every Polfinger 100 . 104 also has a leading edge 156 and opposite a flank 160 , each one between the base 148 and the top 152 of the pole finger extend. The name of a flank 156 . 156 as leading or following refers to the direction of movement of the pole finger relative to the stator core teeth 84 as by the arrow 144 shown. The leading and the following flanks 156 . 160 from every Polfinger 100 of the front pole piece 44 each define a leading edge surface 164 and a following flank surface 168 , The leading and following flanks 156 . 160 from every Polfinger 104 the rear pole piece 48 define leading edge surfaces accordingly 172 and following flank surfaces 176 ,

Eder Polfinger 100 also defines a radial outer surface 180 and a radial inner surface 184 , each in the circumferential direction between opposite leading and following flank surfaces 164 . 168 extend. Every Polfinger 104 also defines a radially outer surface 188 and a radially inner surface 192 , each in the circumferential direction between its opposite leading and following flank surfaces 172 . 176 extends. As in the 2 and 5A As shown, each radially outer surface lies 180 . 188 along a corresponding surface line 196 which are essentially parallel to the central axis 60 is, so that a cylinder by the multiplicity of the assembled surface lines 196 can be defined. The radially outer surfaces 180 . 188 the alternating pole finger 100 . 104 define the substantially cylindrical outer peripheral surface of the rotor 56 ,

Regarding each Polfingers 100 . 104 in the 1 to 8th and 10 which are shown as being substantially pyramidal is the corresponding radially inner surface 184 . 192 near its base or its proximal end 148 closer to the central axis 60 and near its tip or its distal end 152 which may be flattened as shown, farther away from the central axis 60 , Thus, each pyramidal Polfinger 100 . 104 relative to the axis 60 between its radial outer surface 180 . 188 and its radial inner surface 184 . 192 at its proximal end or base 148 radially thicker than at its distal end or tip 152 , When viewed in the radial direction, in addition, each pyramid-shaped Polfinger tapers 100 . 104 while the pole finger away from its corresponding hub section 92 . 96 extends, and is thus in the circumferential direction between its leading and its subsequent edge 156 . 160 at its proximal end 148 wider and narrower at its distal end 152 , So you can understand that every Polfinger 100 . 104 may be substantially V-shaped both when viewed in the radial direction relative to the central axis 60 as well as in a direction perpendicular to an imaginary plane in which both the corresponding surface line 196 So also the central axis 60 lie. In other words, each of the mainly pyramidal Polfinger 100 . 104 essentially hexahedral, when at its base 148 is cut by an imaginary plane perpendicular to the central axis 60 oriented, and flattened at its peak.

Like the different ones 1 to 8th can be clearly understood, is also the corresponding thickness of each Polfingers between its radially outer surface 180 . 188 and its radially inner surface 184 . 192 essentially uniform between its leading and trailing flanks 156 . 160 when viewed in imaginary planes perpendicular to the central axis, at different distances axially along each pyramidal pole finger 100 . 104 (ie at different axial locations in directions substantially parallel to the central axis 60 lie). Apart from slight curvatures of the radial inner and outer surfaces 180 . 188 . 184 and 192 around the central axis 60 according to the cylindrical shape of the rotor 56 (convex in the case of the radially outer surfaces 180 . 188 and concave in the case of the radially inner surfaces 184 . 192 ), these are areas 180 . 188 . 184 and 192 essentially flat and featureless between leading and trailing flanks 156 . 160 her respective pole finger.

In some known machines 20 have the Polfinger 100 . 104 another geometry rather than the substantially pyramidal shape discussed above. For example, the pole pieces 44 . 48 according to 9 instead Polfinger or segments 100 . 104 when viewed radially relative to the central axis 60 are substantially rectangular in shape. As with the substantially pyramidal pole segments described above, the pole fingers or segments 100 . 104 the well-known claw pole pieces 44 or 48 , in the 9 are shown, respectively: A base or a proximal end 148 in places between the cavities 108 with the corresponding pole piece hub section 92 . 96 connected, a tip or a distal end 152 towards its corresponding base 148 where the top 152 of the pole finger of the pole piece 44 . 48 close to the base 148 the Polfingers of the other pole piece 44 . 48 is arranged, a leading edge 156 , an opposite following flank 160 , where the leading and following flanks 156 . 160 yourself between the Polfingerbasis 148 and the top 152 extend. The substantially parallel leading and trailing edges 156 . 160 every Polfingers 100 define the leading edge surface 164 or the following flank surface 168 , where the leading and following flanks 156 . 160 every Polfingers 104 the leading flank surface 172 or the following flank surface 176 define. As explained above, the designation of an edge refers 156 . 160 as leading or following the direction of movement of the pole fingers relative to the stator core teeth 84 as by the arrow 144 specified.

In contrast to the substantially pyramidal pole segments described above, in the example of FIG 9 however, the leading and following flanks 156 . 160 substantially parallel to one another and to the central axis 60 , The illustrated Polfingerspitzen or distal ends 152 here are flat and every Polfinger 100 . 104 can be essentially hexahedral if it is at its base 148 is cut by an imaginary plane perpendicular to the central axis 60 is oriented. At the in 9 illustrated embodiment defines each Polfinger 100 . 104 a radially outer surface 180 . 188 and a radially inner surface 184 . 192 (in 9 Not shown). As with the substantially pyramidal Polfingern lies each radially outer, rectangular surface 180 . 188 along a corresponding surface line 196 which are substantially parallel to the central axis 60 is, wherein the cylindrical rotor shape by the arrangement of the surface lines 196 can be defined. Regarding each Polfingers 100 . 104 extends its corresponding radially outer surface 180 . 188 over a substantially equal distance between the leading edge 156 and the next flank 160 that face each other in the circumferential direction. Similarly, its corresponding radially inner surface extends 184 . 192 over a substantially equal distance between the leading edge 156 and the opposite flank opposite 160 , Consequently, every Polfinger has 100 . 104 a substantially rectangular shape when viewed in the radial direction as mentioned above.

In the 9 illustrated Polfinger 100 . 104 may also each be substantially shaped like a rectangular parallelepiped or a cuboid, when viewed in a direction perpendicular to an imaginary plane in which the corresponding surface line 196 and the central axis are the thickness of each pole finger 100 . 104 between its corresponding radially outer surface 180 . 188 and radially inner surface 184 . 192 is substantially constant along its axial direction, ie, in a direction substantially parallel to the surface line 196 is. Consequently, every Polfinger has 100 . 104 when viewed in a tangential direction, perpendicular to the central axis 60 a substantially rectangular shape. Apart from the surfaces 180 . 188 . 184 . 192 , the slight curvatures about the central axis 60 according to the cylindrical shape of the rotor 56 have (convex in the case of the radially outer surfaces 180 . 188 and concave in the case of the radially inner surfaces 184 . 192 ), are the surfaces 180 . 188 . 184 and 192 the substantially cuboid Polfinger 100 . 104 between their respective leading and trailing Polfinger flanks 156 . 160 essentially flat. In addition, the opposing radial outer surfaces 180 . 188 and the radially inner surfaces 184 . 192 each substantially cuboidal Polfingers 100 . 104 essentially parallel. In other words, the corresponding thickness of each pole finger is between its radially outer surface 180 . 188 and radially inner surface 184 . 192 essentially constant in imaginary planes perpendicular to the central axis 60 at different distances along each pyramidal Polfingers 100 . 104 (ie at distances in directions that are substantially parallel to the surface lines 196 run). A known electric machine with pole fingers or pole segments having leading and trailing edges which are substantially parallel to one another and to the central axis of the machine is disclosed in US Pat U.S. Patent No. 7,973,444 entitled "Electric machine and rotor for same", owned by the assignee of the present application.

As mentioned above, in known rotary electric machines, such as a generator 20 the radial inner surfaces 184 . 192 the Polfinger regardless of whether their Polfinger 100 . 104 are substantially pyramidal or substantially cuboidal, substantially flat or have only a very small concave curvature about the central axis 60 between their respective leading and trailing edges 156 . 160 at different locations along the axial length of the pole finger, ie in directions parallel to the surface lines 196 , The curvature of the radially inner surfaces 184 . 192 if present, is near the pole finger base or the proximal end 148 more pronounced than in the vicinity of the Polfingerspitze or the distal end 152 as by comparing the 5F - 5H and 7B - 7E seen.

It is also known to use permanent magnets in the rotors of rotating electrical machines such as generators. In some known generators are very strong permanent magnets 200 between adjacent claw-pole fingers 100 . 104 arranged to that of the exciting coil 88 supplemented magnetic field. Such magnets 200 which are optional are in the 6 - 9 shown. For the permanent magnets 200 Any permanent material can be used, for example neodymium-iron-boron, samarium-cobalt or ferrite. Generators utilizing both the flux of an excitation coil and the flux of permanent magnets coupled to a stator coil are referred to as hybrid generators. As 10 shows, stop at a hybrid generator 20 permanent magnets 200 a permanent magnetic flux across the channels 204 upright, the otherwise air gaps between the claw pole segments 100 . 104 would. The Klauenpolsegmente are magnetic in a hybrid generator to the permanent magnets 200 in channels 204 are arranged and from the rotor 56 and coupled to a portion of the stator structure, thereby coupling substantial magnetic flux through the stator structure. The magnetic flux course 208 is in 10 indicated by dashed lines. When the field coil 88 is not energized, that of the permanent magnets 200 generated magnetic flux through the rotor 56 diverted. However, if the field coil 88 is energized by the permanent magnets 200 In addition to the electromagnetically generated magnetic flux resulting from excitation of the field coil, magnetic flux generated across the stator / rotor air gap 212 at. Depending on the desired output of the hybrid generator 20 can the effect of permanent magnets 200 on the river via the radial stator / rotor air gap 212 supplement or amplify the electromagnetic flux generated by the direct current flowing in one direction through the field coil 88 is directed. The effect of permanent magnets on the flux across the stator / rotor air gap can also be reduced or reversed by electromagnetic flux generated by direct current flowing in the opposite direction through the field coil 88 flows. Damping / amplification control circuits for generators are known in the art and may be designed differently. One of these control circuits is in the above U.S. Patent No. 7,973,444 disclosed.

The channels 204 may be oriented as described above. As a rule, the orientation and shape of the permanent magnets 200 similar. Consequently, permanent magnets 200 essentially prismatic with six substantially flat sides. By the permanent magnets 200 are substantially prismatic, are substantially symmetrical contact surfaces at their respective contact surfaces with the leading and following flank surfaces 164 . 168 . 172 . 176 created. The prismatic permanent magnet 200 is shown here in an exemplary form, it being understood that other forms of permanent magnets will be apparent to those skilled in the art. As shown here, every permanent magnet has 200 a pair of circumferentially opposite pole faces 216 , where the polarized sides 216N and 216S correspond to the corresponding magnetic polarities N and S. The polarities of the permanent magnets alternate so that adjacent magnets have opposite polarity. Therefore, it can be seen that Klauenpolfinger 100 on permanent pole sides 216N abut and have a common first polarity (ie N) and Klauenpolfinger 104 on magnetic pole sides 216S and have a second common polarity (ie S). The pol pages 216N . 216S the magnets 200 immediately adjacent to the corresponding leading and trailing edge surfaces 164 . 168 . 172 . 176 the Polfinger 100 and 104 at. As mentioned above, all pole fingers have 100 magnetic polarity N and all pole fingers 104 magnetic polarity S. All permanent magnet pole faces 216N borders on the flank surfaces 164 . 186 of the respective N Polfingers 100 at. Accordingly, all permanent magnet pole faces are adjacent 216S to the flank surfaces 172 . 176 every S Polfingers 104 at. The above arrangement is generally well known to those skilled in the art.

If permanent magnets 200 to increase the machine power between the claw poles 100 . 104 a generator 20 are inserted, is usually the air gap channel 204 machined or otherwise adapted to provide a constant width between opposing leading and trailing Polfinger flank surfaces for receiving the magnets 164 . 168 . 172 . 176 given is. The shape of the claw pole pieces 44 . 48 however, used in known hybrid generators is not for maximizing the benefits of the permanent magnets 200 optimized. Instead, the design of the pole pieces of such hybrid machines and in particular the design of their pole segments or fingers 100 . 104 from the design of a conventional claw pole rotor without permanent magnets, designed to maximize machine performance without the addition of permanent magnets to the claw pole rotor. Simply following this practice does not fully exploit the potential benefits of adding magnets to claw pole rotors.

A rotary electric machine configured to maximize the advantageous aspects of a rotor equipped with permanent magnets would be a desirable improvement in the art.

SHORT VERSION

The present disclosure aims to provide such a rotary electric machine and a rotor. The present disclosure teaches a pole piece configuration that maximizes the performance of its claw pole segments when used with permanent magnets by modifying the pole geometry. The shape of the radially inner bottom of the pole finger near the tip portion is designed to be significantly concave. This minimizes flow loss from the tip or distal end of a first pole finger or segment to the base or proximal end of a circumferentially adjacent second pole finger or segment, wherein the first pole segment tip overlaps the second pole segment base. Nevertheless, the first pole finger or first pole finger segment may also have its full radial thickness along the sides of the permanent magnet disposed between the first and second pole fingers, facilitating full utilization of flux generation of the magnet.

The sides of the pole finger against which the permanent magnets abut are substantially flat and have a constant radial depth or thickness over the full axial length of the pole finger. Although the embodiment of the improved pole finger geometry is shown as having a substantially cuboidal bounding surface having a substantially rectangular cross section, it will be understood that the teachings of the present disclosure are equally applicable to conventional substantially pyramidal generator claw pole segments or fingers. The teachings of the present disclosure equally apply to brushed and brushless generators.

The advantage of this geometry is that for a given magnetically active axial length of the rotor, the magnetic benefit of a substantially longer permanent magnet in the rotor is possible. This significantly increases the performance of the electric machine by generating much higher levels of flux coupling between the stator and the rotor for a given axial stack length of the rotor and / or stator than conventional generators. Second, the concave radially inner surface shape of the pole finger provides a natural air passage that allows for axial air flow through the rotor assembly for improved cooling.

Polfinger geometry in accordance with the present disclosure has been found through the use of three-dimensional finite element analysis (3D FEA) magnetic modeling and extensive design work. Measured outputs with actual generator prototypes gave output currents twice that of conventional claw-pole generators of comparable size, a significant improvement over the prior art.

The present disclosure provides a rotor for a rotary electric machine, the rotor having a first pole piece and second pole piece each having a corresponding magnetic hub arranged for rotation about an axis, the first and second pole piece hubs being disposed along this axis are arranged at a distance from each other. The rotor further includes a plurality of magnetic first pole fingers and a plurality of magnetic second pole fingers spaced from each other and extending between the first and second pole piece bosses. Each pole finger has a proximal end and an axially opposite distal end, wherein the proximal ends of the first and second pole fingers are respectively connected to the first and second pole piece hub. The first and second pole fingers alternate circumferentially about the axis. Each pole finger has a corresponding radially inner surface defining a cavity which extends axially from the distal end to an end of the cavity. With respect to each pole finger, the radial distance between the axis and the radially inner surface at a corresponding axial location between the distal end and the end of the cavity is substantially greater within the cavity than outside the cavity.

Another aspect of the rotor is that with respect to each pole finger, the end of the cavity is located between the proximal end and the distal end.

Another aspect of the rotor is that with respect to each pole finger, the radial distance between the axis and the radially inner surface within the cavity is greater at a first axial location lying between the distal end and the end of the cavity than at a second axial one Location that is between the first axial location and the end of the cavity.

Another aspect of the rotor is that each pole finger has circumferentially opposed leading and trailing edges and the corresponding cavity lies between the leading and trailing edges.

Another aspect of the rotor is that with respect to each pole finger, the cavity has a width that varies in a direction perpendicular to the axis, the width being greater at a first axial location that is between the distal end and the end of the cavity as the width is at a second axial location lying between the first axial location and the end of the cavity.

Another aspect of the rotor is that with respect to each pole finger, the cavity in an imaginary plane perpendicular to the axis has a substantially triangular shape.

Another aspect of the rotor is that with respect to each pole finger, the cavity in an imaginary plane parallel to the axis has a substantially triangular shape.

Another aspect of the rotor is that the end of the excavation of each pole finger defines a vertex of the cavity.

Another aspect of the rotor is that with respect to each pole finger at the corresponding end of the cavity and the distal end, the radially inner surface has a radially constant distance from the axis at locations outside the cavity.

Another aspect of the rotor is that each pole finger defines a radially outer surface and the corresponding pole finger has a radial thickness between the radially inner surface and the radially outer surface. The radial thickness at a first location outside the cavity is greater than the radial thickness at a second location within the cavity.

An additional aspect of the rotor is that each pole finger has circumferentially opposed leading and trailing flanks, and the first location lies circumferentially between the cavity and either the leading or trailing edge of the corresponding pole finger.

An additional aspect of the rotor is that the first location lies between the proximal end and the end of the cavity of the corresponding pole finger.

Another aspect of the rotor is that each pole finger has circumferentially opposed leading and trailing edges. The corresponding radially inner surface extends circumferentially between the leading and trailing flanks, the leading and trailing flanks being substantially parallel to the axis.

Another aspect of the rotor is that the first pole fingers are magnetic N pole fingers and the second pole fingers are magnetic S pole fingers. Of the Rotor also has at least one magnet which is arranged between a circumferentially adjacent pair of N and S Polfingern. The magnet has opposing N and S pole sides, with the magnetic N pole side coupling to the N pole fingers and the magnetic pole side coupling to the S pole finger.

Another aspect of the rotor is that each pole finger has circumferentially opposed leading and trailing flank surfaces and the corresponding radially inner surface extends circumferentially between the leading and trailing flank surfaces. The rotor further includes at least one magnet disposed between the coupling leading and trailing edge surfaces of a pair of circumferentially adjacent first and second pole fingers and having magnetically opposite pole faces. Each magnetically opposite pole face of the magnet or magnets abuts either the leading or trailing edge surface of the pole finger substantially along the entire length of the corresponding pole finger between the proximal and distal ends of the pole finger.

Another aspect of the rotor is that it also includes an exciter coil disposed about the axis between the first and second pole piece hubs. The magnetic polarity designations N and S of the first and second pole piece hub are selectively determined by a selected flow direction of the electric current through the exciting coil.

The present disclosure also provides a rotary electric machine having a rotor as described above, a stator surrounding the rotor, and a housing connected to the stator. The rotor is supported by the housing for rotation about the stator.

The present disclosure also provides a rotor for a rotary electric machine, wherein the rotor has a pair of magnetic first and second pole pieces, each having a corresponding hub. The first and second pole piece hubs are spaced apart along an axis and have first and second pluralities of pole fingers, respectively. The first and second pole fingers are each spaced apart and distributed about the axis to define a substantially cylindrical outer rotor surface. Each pole finger has a base attached to the first and second pole piece hub, respectively, and extends toward the other pole piece hub. Each pole finger of the first and second plurality terminates at a tip adjacent to the bases of a pair of pole fingers contained within the other of the first and second pole fingers. Each Polfingerspitze is provided with a radially inwardly open cavity. The cavity has a length extending axially inwardly from the tip toward the base of the corresponding pole finger to one end of the cavity. The cavity has a width extending between opposite flanks of the corresponding pole finger in a direction substantially perpendicular to the axis and a depth extending substantially radially into the corresponding pole finger. At least one of these two dimensions of the cavity, namely width or depth, reduces along the cavity length in the axial inward direction.

Another aspect of the rotor is that the first pole fingers are magnetic N pole fingers and the second pole fingers are magnetic S pole fingers. The rotor also includes at least one magnet disposed between a circumferentially adjacent pair of N and S pole fingers, the magnet having opposing N and S pole sides. The one or more magnetic pole sides couple to the N pole finger and the magnetic pole side (s) couple to the pole finger.

The present disclosure also provides a rotary electric machine having a rotor as described above, a stator surrounding the rotor, and a housing connected to the stator. The rotor is supported by the housing for rotation relative to the stator.

BRIEF DESCRIPTION OF THE DRAWINGS

The various objects, features and attendant advantages of the present invention will become more apparent and more readily understood when considered in connection with the accompanying drawings. It should be understood that the appended drawings are not necessarily to scale or to the same scale, in particular, the scale of some elements of the drawings may be exaggerated to clarify features of these elements. Like reference numerals designate the same, similar or corresponding parts throughout the several views, wherein:

1 FIG. 12 is a sectional view of a known generator assembly to which the teachings of the present disclosure may be applied; FIG.

2 Figure 11 is a partially cutaway front perspective view of a stator and rotor of a conventional generator to which the teachings of the present disclosure apply;

3 shows a sectional side view of a conventional generator rotor along the line 3-3 of 4 ;

4 shows a detail of a front view of a conventional generator rotor;

5A shows a perspective view of a conventional pole piece with Polfingern, which are substantially pyramid-shaped;

5B shows an axial view of one end of the pole piece of 5A ;

5C shows an axial view of the opposite end of the pole piece of 5B ;

5D shows a side view of the pole piece of 5C ;

5E shows a sectional view of the pole piece of 5C along the line 5E-5E;

5F shows a sectional view of a Polfingers the pole piece of 5D along the line 5F-5F;

5G shows a sectional view of a Polfingers the pole piece of 5D along the line 5G-5G;

5H shows a sectional view of a Polfingers the pole piece of 5D along the section line 5H-5H;

6 shows an exploded view of a detail of a conventional rotor having substantially pyramidal Polfingern and optional permanent magnet;

7A shows a sectional side view of a conventional generator rotor with permanent magnets along the line 7A-7A of 8th ;

7B is an axial end view of the rotor of 7A along the line 7B-7B and shows the Polfingerspitze;

7C is a rotor cutaway view 7A along the line 7C-7C and shows an axial sectional view of the Polfingers;

7D is a sectional view of the rotor of 7A along the line 7D-7D and shows an axial cross section of the Polfingers and the permanent magnets;

7E is a sectional view of the rotor of 7A along the line 7E-7E and shows an axial cross section of the Polfingers and the permanent magnets;

8th shows a detail of a front view of a conventional generator rotor with permanent magnets;

9 shows an exploded view of a portion of a conventional rotor having substantially cuboidal Polfingern and optional permanent magnet;

10 FIG. 12 is an enlarged partial cross-sectional view of a conventional permanent magnet rotor and a stator core (with the excitation field coil and the stator windings removed) illustrating the magnetic flux path therebetween; FIG.

11 FIG. 4 is a fragmentary exploded view of a portion of one embodiment of a rotor according to the present disclosure; FIG.

12 FIG. 12 is a cross-sectional side view of a generator rotor according to the present disclosure taken along line 12--12 of FIG 13 ;

13 FIG. 12 is a fragmentary front view of a generator rotor according to the present disclosure; FIG.

14A FIG. 4 is a sectional side view of a generator according to the present disclosure taken along line 14A-14A of FIG 15 ;

14B is a partially sectioned detail view of the rotor of 14A along the line 14B-14B and shows an axial end view of a Polfinger and permanent magnets;

14C is a sectional detail view of the rotor of 14A along the line 14C-14C and shows an axial sectional view of the Polfingers and the magnets;

14D is a sectional view of a detail of the rotor of 14A along the line 14D-14D and shows an axial sectional view of the pole fingers and magnets;

15 FIG. 12 is a fragmentary front view of a generator rotor according to the present disclosure; FIG.

16 shows an enlarged detail view of an embodiment of a Polfingerspitze and permanent magnets according to the present disclosure;

17 shows a sectional side view of a generator rotor and stator according to the prior art for comparison 1 ;

18 FIG. 12 is a cross-sectional side view of a generator rotor and stator according to the present disclosure for comparison. FIG 17 ; and

19 12 is a graph showing the performance improvement of a hybrid generator according to the present disclosure as compared with a prior art non-hybrid generator.

Corresponding reference numerals designate corresponding parts throughout the several views. Although the drawings show embodiments of the disclosed apparatus, the drawings are not necessarily to scale or scale, and certain features may be exaggerated in order to better illustrate and explain the present disclosure. In the accompanying drawings, which show sectional views, hatching of various sectional elements has been omitted for clarity. It should be understood that this omission of hatching is for the purpose of clarity of illustration only.

DETAILED DESCRIPTION OF EMBODIMENT (S)

The invention is suitable for various modifications and alternative embodiments. Her specific embodiment, which is illustrated by way of example in the drawings, will be described in detail here. The embodiment of the present disclosure is chosen and described so that those skilled in the art can appreciate and understand the principles and practices of the present disclosure. It should be understood, however, that the drawings and detailed description are not intended to limit the invention to the particular form disclosed, but on the contrary, the invention is intended to embrace all modifications, equivalents, and alternatives which the spirit and scope of the present invention, as well is defined in the appended claims.

When reference is made below and in the drawings to a rotary electric machine or rotor according to the present disclosure, its structural elements corresponding to the prior art structural elements discussed above are provided with a corresponding reference numeral which is deleted. Thus, for example, an embodiment of the above-discussed rotating electric machine 20 and the rotor 56 , which is modified according to the present disclosure, as a rotary electric machine 20 ' and rotor 56 ' designated. Corresponding structural elements of the machine 20 ' , which are substantially unchanged with respect to the prior art discussed above, are accordingly designated by common reference numerals. The magnetic flux path, though he is at the machines 20 and 20 ' is not structural and therefore consistent with the reference number 208 designated.

11 shows a rotor 56 ' according to the present disclosure. The illustrated embodiment of the rotor 56 ' is similar apart from the configuration of his pole fingers 100 ' 104 ' and possibly the axial length of its permanent magnets 200 ' largely a conventional rotor 56 , which is essentially cuboid pole fingers 100 . 104 and prism-shaped magnets 200 Has.

As mentioned above, in conventional rotary electric machines 20 regardless of whether her pole fingers 100 . 104 are substantially pyramidal or substantially cuboid, the radially inner Polfingerflächen 184 . 192 essentially flat or between their leading and trailing flanks 156 and 160 with only a very small concave curvature about the central axis 60 Mistake. This surface curvature, if present, is near the pole finger base or proximal end 148 more pronounced than in the vicinity of the Polfingerspitze or the distal end 152 what a comparison of 5F - 5H with the 7B - 7E shows. This property of the radially inner Polfingerflächen 184 . 192 is both with rotors 56 , the permanent magnets 200 and those who do not. As explained above, it appears that the configurations of known pole fingers 100 . 104 Although possibly to some extent for use in rotors 56 that are not permanent magnets 200 have been optimized, but the pole finger configurations are adopted essentially unchanged when magnets are inserted into these rotors. In other words, though adding the magnets 200 in known rotors 56 the performance of the machine 20 (which may be, for example, a hybrid generator), are the pole segments or fingers 100 . 104 of these known machines, between which the added permanent magnets 200 to be arranged, essentially unchanged.

The present disclosure provides pole pieces 44 ' . 48 ' with modified Polfingerkonfigurationen when using with permanent magnets 200 ' the power of the rotor 56 ' and his machine 20 ' maximize. How to best in the 12 to 16 sees, the rotor points 56 ' the machine 20 ' essentially identical pole pieces 44 ' 48 ' on. The corresponding pole segments or fingers 100 ' . 104 ' the pole pieces 44 ' . 48 ' have a clear other form than Polfinger 100 ' . 104 ' conventional pole pieces 44 ' . 48 ' , In particular, the embodiments of the radially inner surfaces 184 ' . 192 ' the Polfinger 100 ' . 104 ' differ significantly from those of the corresponding radial inner surfaces 184 . 182 conventional pole fingers 100 . 104 , A comparison of 14B - 14D and 5F - 5H and or 7B - 7E illustrates this distinction best, although the Polfinger shown 100 ' . 104 ' According to the present disclosure are substantially cuboidal type and the illustrated Polfinger 100 . 104 are of the prior art substantially pyramidal type. It must be understood that the teachings of the present disclosure also Polfinger 100 ' . 104 ' other embodiments than the illustrated embodiments relate, for example, Polfinger, which are substantially pyramidal. The comparison shows that according to the present disclosure, the corresponding radially inner surfaces 184 ' . 192 ' from every Polfinger 100 ' . 104 ' near the area of the pole finger tip or the distal pole finger end 152 ' are clearly concave, resulting in flow discharges from the tip or the distal end 152 ' a first pole finger or segment 100 ' or 104 ' to the base or the proximal end 148 ' a circumferentially adjacent second pole finger or segment 100 ' . 104 ' in the area of the rotor 56 ' minimized where the first pole segment tip 152 ' the second pole segment base 148 ' overlaps. The radially inner surfaces 184 . 192 conventional pole fingers 100 . 104 are essentially flat surfaces, wherein any small internal cambers are negligible and only the diameter of the rotor 56 correspond. In comparison, every inside arch is defined by the radially inward open cavity 220 is defined, which in the radially inner surfaces 184 ' . 192 ' is arranged, much larger. As shown, the excavation is 220 defined by a substantially triangular pyramidal cavity formed in the distal end 152 ' the Polfinger 100 ' 104 ' is shaped. The base of this triangular cavity can be as at the Polfingerspitze 152 ' be viewed arranged. Its vertex, the end of the excavation 220 , as in one place 224 can be viewed arranged axially between the proximal and distal ends 148 ' . 152 ' the Polfinger lies, as best in 12A . 14A and 16 sees.

In addition, every Polfinger or segment 100 ' . 104 ' also its full radial thickness or depth between the radially outer surface 180 . 188 and the radially inner surface 184 ' . 192 ' along the leading and following flanks 156 . 160 have, where in each case the corresponding peripheral side 216 the magnets 200 ' entirely on a corresponding leading or trailing edge surface 164 ' . 168 ' . 172 ' . 176 ' can be present. The possibility of both sides the full area of each magnetic pole side 216N . 216S and its associated, cooperating leading or following Polfinger flank surface 164 ' . 168 ' . 172 ' . 176 ' Coupling facilitates the full utilization of magnetic flux generation. In particular, the leading or following flank surfaces 164 ' . 168 ' . 172 ' . 176 ' substantially planar and have constant radial depth or thickness over the axial full length of the pole finger 100 ' . 104 ' ie in its full length in a surface line 196 parallel direction. Although the embodiment of the improved pole finger geometry is illustrated as having a substantially cuboidal boundary surface having a substantially square cross section, it is to be understood that the teachings of the present disclosure equally well refer to conventional, substantially pyramidal generator claw pole segments or claw pole fingers. The teachings of the present disclosure as well relate to brushless generators as brushed generators.

As the 17 and 18 show an advantage of the Polfingergeometrie the machine 20 ' compared to a conventional machine 20 in that for a given magnetically active axis length (L1 = L1) of the rotor 56 . 56 ' the magnetic use of a much longer permanent magnet 200 ' (L3 >> L2) in the rotor 56 ' which allows, in a practical way, a larger axial stacking length of the stator (L5> L4). This significantly increases the performance of the electric machine 20 ' compared to the machine 20 by putting in the machine 20 ' a much higher degree of flux coupling between the stator 52 ' and the rotor 56 ' for a given axial staple length of the rotor (L1 = L1) and / or a given axial plate stack length of the stator (L4 = L5) is generated.

A second advantage of the Polfinger geometry of the machine 20 ' opposite the machine 20 is that through the excavation 220 in the radially inner surface 184 ' . 192 ' of the pole finger 100 ' . 104 ' a natural air passage is formed, which has a comparatively larger axial air flow through the rotor assembly 56 ' for a comparatively improved cooling.

As mentioned above, the pole finger geometry according to the present disclosure has been found through the use of three-dimensional finite element analysis (3D FEA) magnetic modeling and extensive development work. Current generator prototypes according to the present invention (ie prototypes of the machines 20 ' ) have yielded measured output current values that are 200% of what conventional claw pole generators of comparable size provide without magnets. This performance improvement, as with existing 14 volt generators in operation at 25 ° C shown is in 19 shown. In 19 gives the curve 228 the performance of a prototype hybrid generator 20 ' according to the present disclosure having substantially parallelepiped claw-pole fingers. The curve 232 gives the performance of a standard non-hybrid generator 20 (without permanent magnets of the rotor) according to the prior art, which has substantially pyramid-shaped claw pole fingers.

• 1. Rotor für eine rotierende elektrische Maschine, der Rotor enthaltend: ein erstes Polstück und ein zweites Polstück, die jeweils eine entsprechende magnetische Nabe haben, die zur Rotation um eine Achse angeordnet ist, wobei die ersten und zweiten Polstücknaben in einen Abstand entlang der Achse angeordnet sind, eine Vielzahl von magnetischen ersten Polfinger und eine Vielzahl von magnetischen zweiten Polfingern, die in einem Abstand voneinander angeordnet sind und sich zwischen der ersten und der zweiten Polstücknabe erstrecken, wobei jeder Polfinger ein proximales Ende und ein axial gegenüberliegendes distales Ende hat, die proximalen Enden der ersten und zweiten Polfinger mit der ersten bzw. der zweiten Polstücknabe verbunden sind, die ersten und zweiten Polfinger in Umfangsrichtung alternierend um die Achse angeordnet sind, jeder Polfinger eine entsprechende radial innere Fläche hat, die eine Aushöhlung definiert, welche sich axial von dem distalen Ende zu einem Ende der Aushöhlung erstreckt, und bezüglich jedes Polfingers der radiale Abstand zwischen der Achse und der radial inneren Fläche an einer entsprechenden axiale Stelle zwischen dem distalen Ende und dem Ende der Aushöhlung innerhalb der Aushöhlung wesentlich größer als außerhalb der Aushöhlung ist.
• 2. Der Rotor der bevorzugten Ausgestaltung 1, wobei das Ende der Aushöhlung bei jedem Polfinger zwischen dem proximalen und dem distalen Ende angeordnet ist.
• 3. Der Rotor der bevorzugten Ausgestaltung 1 oder 2, wobei bei jedem Polfinger der radiale Abstand zwischen der Achse und der radial inneren Fläche innerhalb der Aushöhlung an einer ersten axialen Stelle, die zwischen dem distalen Ende und dem Ende der Aushöhlung liegt, größer ist als an einer zweiten axialen Stelle, die zwischen der ersten axialen Stelle und dem Ende der Aushöhlung ist.
• 4. Der Rotor einer der vorstehenden bevorzugten Ausgestaltungen, wobei jeder Polfinger sich in Umfangsrichtung gegenüberliegende führende und folgende Flanken hat und die dazugehörende Aushöhlung zwischen den führenden und folgenden Flanken angeordnet ist.
• 5. Der Rotor einer der vorstehenden bevorzugten Ausgestaltungen, wobei bei jedem Polfinger die Aushöhlung eine Breite hat, die sich in einer Richtung senkrecht zu der Achse ändert, und die Breite an einer ersten axialen Stelle, die zwischen dem distalen Ende und dem Ende der Aushöhlung liegt, größer ist als die Breite an einer zweiten axialen Stelle, die zwischen der ersten axialen Stelle und dem Ende der Aushöhlung ist.
• 6. Rotor einer der vorstehenden bevorzugten Ausgestaltungen, wobei bei jedem Polfinger die Aushöhlung eine im Wesentlichen dreieckige Form in einer imaginären Ebene hat, die senkrecht zu der Achse ist.
• 7. Rotor einer der vorstehenden bevorzugten Ausgestaltungen, wobei bei jedem Polfinger die Aushöhlung eine im Wesentlichen dreieckige Form in einer imaginären Ebene hat, die parallel zu der Achse ist.
• 8. Rotor einer der vorstehenden bevorzugten Ausgestaltungen, wobei das Ende der Aushöhlung jedes Polfingers einen Scheitelpunkt der Aushöhlung definiert.
• 9. Rotor einer der vorstehenden bevorzugten Ausgestaltungen, wobei bei jedem Finger an dem dazugehörenden Ende der Aushöhlung und dem distalen Ende die radial innere Fläche an Stellen außerhalb der Aushöhlung von der Achse radial gleichen Abstand hat.
• 10. Rotor einer der bevorzugten Ausgestaltungen 1 bis 3, wobei jeder Polfinger eine radial äußere Fläche definiert, der einzelne Polfinger eine radiale Dicke zwischen der radial inneren Fläche und der radial äußeren Fläche hat, und die radiale Dicke an einer ersten Stelle außerhalb der Aushöhlung größer als an einer zweiten Stelle innerhalb der Aushöhlung ist.
• 11. Rotor der bevorzugten Ausgestaltung 10, wobei jeder Polfinger sich in Umfangsrichtung gegenüberliegende führende und folgende Flanken hat, und die erste Stelle in Umfangsrichtung zwischen der Aushöhlung und entweder der führenden oder der folgenden Flanke des entsprechenden Polfingers ist.
• 12. Rotor der bevorzugten Ausgestaltung 10 oder 11, wobei die erste Stelle zwischen dem proximalen Ende und dem Ende der Aushöhlung des entsprechenden Polfingers ist.
• 13. Rotor einer der bevorzugten Ausgestaltungen, wobei jeder Polfinger sich in Umfangsrichtung gegenüberliegende führende und folgende Flanken hat, die entsprechende radial innere Fläche sich in Umfangsrichtung zwischen den führenden und folgenden Flanken erstreckt, und die führenden und folgenden Flanken im Wesentlichen parallel zur Achse sind.
• 14. Rotor einer der vorstehenden bevorzugten Ausgestaltungen, wobei magnetisch die ersten Polfinger N Polfinger und die zweiten Polfinger S Polfinger sind, wobei der Rotor zudem wenigstens einen Magneten enthält, der zwischen zwei in Umfangsrichtung benachbarten Paaren von N und S Polfingern angeordnet ist, der Magnet sich gegenüberliegende N und S Polseiten hat, die magnetische N Polseite an den N Polfinger ankoppelt und die magnetische S Polseite an den S Polfinger ankoppelt.
• 15. Rotor einer der vorstehenden bevorzugten Ausgestaltungen, wobei jeder Polfinger sich in Umfangsrichtung gegenüberliegende führende und folgende Flankenflächen hat und die jeweilige radial innere Fläche sich in Umfangsrichtung zwischen den führenden und folgenden Flankenfläche erstreckt, und der Rotor zudem wenigstens einen Magneten enthält, der zwischen den koppelnden führenden und folgenden Flankenflächen eines Paares von in Umfangsrichtung benachbarten ersten und zweiten Polfingern angeordnet ist und magnetisch entgegengesetzte Polseitenfläche aufweist, wobei jede magnetisch entgegengesetzte Polseitenfläche entweder an der führenden oder der folgenden Polfingerflankenfläche im Wesentlichen entlang der gesamten Länge des entsprechenden Polfingers zwischen dessen proximalen und distalen Ende anliegt.
• 16. Rotor einer der vorstehenden bevorzugten Ausgestaltungen, zusätzlich enthaltend eine Erregerspule, die um die Achse herum zwischen der ersten und der zweiten Polstücknabe angeordnet ist, wobei N und S magnetische Polaritätsbenennungen der ersten und der zweiten Polstücknabe selektiv durch eine gewählte Stromflussrichtung in der Erregerspule bestimmt sind.
• 17. Rotierende elektrische Maschine mit: einem Rotor nach einer der vorstehenden bevorzugten Ausgestaltungen, einem Stator, der den Rotor umgibt, und einem Gehäuse, das mit dem Stator verbunden ist, wobei der Rotor von dem Gehäuse zur Rotation relativ zu dem Stator gestützt wird.
• 18. Rotor für eine rotierende elektrische Maschine, mit: einem Paar magnetischer erster und zweiter Polstücke, die jeweils eine Nabe aufweisen, wobei die erste und zweite Polstücknabe in einem Abstand voneinander entlang einer Achse angeordnet sind und erste bzw. zweite Vielzahlen von Polfingern aufweisen, jede der ersten und der zweiten Vielzahlen der Polfinger in einem Abstand voneinander um die Achse herum verteilt sind, um eine im Wesentlichen zylindrische äußere Rotorfläche zu definieren, jeder Polfinger eine Basis aufweist, die an seiner ersten bzw. zweiten Polstücknabe angebracht ist und sich in Richtung zu der jeweils anderen Polstücknabe hin erstreckt, jeder Polfinger der ersten oder der zweiten Vielzahl von Polfingern in einer Spitze endet, die in der Nähe der Basen eines Paares von Polfingern der jeweils anderen Vielzahl der ersten und zweiten Polfingervielzahl angeordnet ist, wobei jede Polfingerspitze mit einer radial einwärts offenen Aushöhlung versehen ist, die eine Länge hat, welche sich axial einwärts von der Spitze in einer Richtung hin zu der Basis des zugehörigen Polfingers bis zu einem Ende der Aushöhlung erstreckt, und die Aushöhlung eine Breite, die sich zwischen gegenüberliegenden Flanken des entsprechenden Polfingers in einer Richtung erstreckt, die im Wesentlichen senkrecht zu der Achse ist, und eine Tiefe, die sich im Wesentlichen radial in den entsprechenden Polfinger hinein erstreckt, hat, wobei zumindest eine dieser beiden Aushöhlungsabmessungen, nämlich Breite und/oder Tiefe, entlang der Aushöhlungslänge in der Richtung axial einwärts abnimmt.
• 19. Rotor der bevorzugten Ausgestaltung 18, wobei magnetisch die ersten Polfinger N Polfinger und die zweiten Polfinger S Polfinger sind, und wobei der Rotor zudem wenigstens einen Magneten enthält, der zwischen einem in Umfangsrichtung benachbarten Paar von N und S Polfingern angeordnet ist, der Magnet gegenüberliegende N und S Polseiten aufweist, die magnetische N Polseite an den N Polfinger gekoppelt ist und die magnetische S Polseite an den S Polfinger gekoppelt ist.
• 20. Rotierende elektrische Maschine mit dem Rotor der bevorzugten Ausgestaltung 18 oder 19, einem den Rotor umgebenden Stator, und einem mit dem Stator verbundenen Gehäuse, wobei der Rotor von dem Gehäuse zur Rotation relativ zu dem Stator gestützt wird.

The following is a list of preferred embodiments according to the present disclosure:

• A rotor for a rotary electric machine, the rotor comprising: a first pole piece and a second pole piece each having a respective magnetic hub arranged for rotation about an axis, the first and second pole piece hubs being spaced along the axis a plurality of magnetic first pole fingers and a plurality of magnetic second pole fingers spaced apart and extending between the first and second pole piece bosses, each pole finger having a proximal end and an axially opposite distal end proximal ends of the first and second pole fingers are connected to the first and second pole piece hub respectively, the first and second pole fingers are circumferentially arranged alternately about the axis, each pole finger has a corresponding radially inner surface defining a cavity extending axially from the distal end to one end of the Hollow extends, and with respect to each Polfingers the radial distance between the axis and the radially inner surface at a corresponding axial location between the distal end and the end of the cavity within the cavity is substantially greater than outside the cavity.
• 2. The rotor of Preferred Embodiment 1, wherein the end of the cavity in each pole finger is disposed between the proximal and distal ends.
• 3. The rotor of Preferred Embodiment 1 or 2, wherein in each pole finger, the radial distance between the axis and the radially inner surface within the cavity is greater at a first axial location located between the distal end and the end of the cavity at a second axial location that is between the first axial location and the end of the cavity.
• 4. The rotor of any of the foregoing preferred embodiments, wherein each pole finger has circumferentially opposed leading and trailing edges, and the associated cavity is located between the leading and trailing edges.
• 5. The rotor of any one of the above preferred embodiments, wherein in each pole finger the cavity has a width that varies in a direction perpendicular to the axis and the width at a first axial location between the distal end and the end of the cavity is greater than the width at a second axial location that is between the first axial location and the end of the cavity.
• A rotor of any one of the above preferred embodiments, wherein in each pole finger the cavity has a substantially triangular shape in an imaginary plane which is perpendicular to the axis.
• A rotor of any one of the foregoing preferred embodiments, wherein in each pole finger the cavity has a substantially triangular shape in an imaginary plane parallel to the axis.
• A rotor of any of the foregoing preferred embodiments, wherein the end of the cavity of each pole finger defines a vertex of the cavity.
• A rotor of any of the foregoing preferred embodiments, wherein each finger at the mating end of the cavity and the distal end has the radially inner surface at locations outwardly of the cavity radially equidistant from the axis.
• 10. A rotor of one of the preferred embodiments 1 to 3, wherein each pole finger defines a radially outer surface, the individual pole fingers have a radial thickness between the radially inner surface and the radially outer surface, and the radial thickness at a first location outside the cavity is larger as being at a second location within the excavation.
• 11. A rotor of preferred embodiment 10, wherein each pole finger has circumferentially opposed leading and trailing flanks, and is the first circumferential location between the cavity and either the leading or trailing edge of the corresponding pole finger.
• 12. Rotor of the preferred embodiment 10 or 11, wherein the first location between the proximal end and the end of the cavity of the corresponding Polfingers is.
• A rotor of one of the preferred embodiments, wherein each pole finger has circumferentially opposed leading and trailing flanks, the respective radially inner surface extending circumferentially between the leading and trailing flanks, and the leading and trailing flanks being substantially parallel to the axis.
• 14. Rotor of one of the above preferred embodiments, wherein magnetically, the first pole fingers N Polfinger and the second Polfinger S Polfinger, wherein the rotor also at least a magnet disposed between two circumferentially adjacent pairs of N and S pole fingers, the magnet having opposite N and S pole sides, coupling the magnetic N pole side to the N pole finger, and coupling the magnetic pole side to the S pole finger.
• A rotor of any of the foregoing preferred embodiments, wherein each pole finger has circumferentially opposed leading and trailing flank surfaces and the respective radially inner surface extends circumferentially between the leading and trailing flank surfaces, and the rotor further includes at least one magnet interposed between the two coupling and leading edge surfaces of a pair of circumferentially adjacent first and second pole fingers and having magnetically opposite pole side surfaces, each magnetically opposite pole side surface on either the leading or following pole finger edge surface substantially along the entire length of the corresponding pole finger between the proximal and distal thereof End is present.
• 16. A rotor of any of the foregoing preferred embodiments, further including an exciter coil disposed about the axis between the first and second pole piece bosses, wherein N and S selectively determine magnetic polarity designations of the first and second pole piece bosses through a selected current flow direction in the excitation coil are.
• 17. A rotary electric machine comprising: a rotor according to one of the preceding preferred embodiments, a stator surrounding the rotor and a housing connected to the stator, the rotor being supported by the housing for rotation relative to the stator.
• 18. A rotor for a rotary electric machine, comprising: a pair of magnetic first and second pole pieces each having a hub, the first and second pole piece bosses being spaced apart along an axis and having first and second pluralities of pole fingers, respectively; each of the first and second pluralities of pole fingers are spaced apart around the axis to define a substantially cylindrical outer rotor surface, each pole finger having a base mounted on its first and second pole piece hubs and extending in the direction extending to the respective other pole piece hub, each pole finger of the first or the second plurality of Polfingern terminates in a tip, which is arranged in the vicinity of the bases of a pair of Polfingern the respective other plurality of the first and second Polfingervielzahl, each Polfingerspitze with a is provided radially inwardly open cavity, di e has a length which extends axially inwardly from the tip in a direction toward the base of the associated pole finger to an end of the cavity, and the cavity has a width extending between opposite flanks of the corresponding pole finger in a direction is substantially perpendicular to the axis, and has a depth that extends substantially radially into the corresponding pole finger, with at least one of these two cavity dimensions, namely width and / or depth, decreasing axially inwardly along the cavity length in the direction.
• 19. Rotor of the preferred embodiment 18, wherein magnetically the first pole fingers N are Polfinger and the second pole fingers are S Polfinger, and wherein the rotor further comprises at least one magnet disposed between a circumferentially adjacent pair of N and S pole fingers, the magnet opposing N and S pole sides, the magnetic N pole side is coupled to the N Polfinger and the magnetic S Polseite is coupled to the S Polfinger.
• 20. A rotary electric machine with the rotor of the preferred embodiment 18 or 19, a stator surrounding the rotor, and a stator connected to the housing, wherein the rotor is supported by the housing for rotation relative to the stator.

While embodiments have been disclosed above, the invention is not limited to the disclosed embodiments. Instead, the application is intended to cover any variations, applications, or modifications of the present disclosure in accordance with the general principles thereof. In addition, the application is intended to cover such deviations from the present disclosure which appear in the well-known or ordinary practice of the art to which the invention pertains and which are within the scope of the appended claims. Thus, although the disclosed rotary electric machine is a brushed generator, it is to be understood that the teachings of the present disclosure may be practiced with rotors of other types of electric machines, such as electric motors or brushless generators with rotors containing permanent magnets.

For a further discussion of the nature of the use and operation of the invention, the same should be apparent from the foregoing description. With regard to the above description to realize that the optimal scale relationships for the parts of the invention, including variations in size, materials, shape, shape, function and mode of operation, assembly and use, will be readily apparent and obvious to those skilled in the art, and all equivalent relationships, with respect to the illustrations in FIG The drawings and the description of the present invention should be considered.

QUOTES INCLUDE IN THE DESCRIPTION

This list of the documents listed by the applicant has been generated automatically and is included solely for the better information of the reader. The list is not part of the German patent or utility model application. The DPMA assumes no liability for any errors or omissions.

Cited patent literature

• US 7973444 [0017, 0019]

Claims (20)

Rotor ( 56 ' ) for a rotating electrical machine ( 20 ' ), wherein the rotor ( 56 ' ): a first pole piece ( 44 ' ) and a second pole piece ( 48 ' ), each one magnetic hub ( 92 . 96 ) for rotation about an axis ( 60 ), the first and second pole piece hubs ( 44 ' . 48 ' ) at a distance from each other along the axis ( 60 ) are arranged; several magnetic first pole fingers ( 100 ' ) and a plurality of magnetic second pole fingers ( 104 ' ), which are spaced apart from each other and between the first and the second pole piece hub ( 92 . 96 ), each Polfinger ( 100 ' . 104 ' ) a proximal end ( 148 ' ) and an axially opposite distal end ( 152 ' ), the proximal ends ( 148 ' ) of the first and second pole fingers with the first and the second pole piece hub ( 92 . 96 ), the first and second pole fingers ( 100 ' . 104 ' ) in the circumferential direction alternately about the axis ( 60 ) are arranged, each Polfinger ( 100 ' . 104 ' ) has a corresponding radially inner surface ( 184 ' . 192 ' ) having a cavity ( 220 ) defined axially from the distal end ( 152 ' ) to an end of the excavation ( 224 ), and at each Polfinger ( 100 ' . 104 ' ) at an associated axial location between the distal end ( 152 ' ) and the end of the excavation ( 224 ) the radial distance between the axis ( 60 ) and the radially inner surface ( 184 ' . 192 ' ) in the excavation ( 220 ) is much larger than outside the cavity ( 220 ). Rotor ( 56 ' ) according to claim 1, wherein at each pole finger ( 100 ' . 104 ' ) the end of the excavation ( 224 ) between the proximal end ( 148 ' ) and the distal end ( 152 ' ) lies. Rotor ( 56 ' ) according to claim 1 or 2, wherein at each pole finger ( 100 ' . 104 ' ) the radial distance between the axis ( 60 ) and the radially inner surface ( 184 ' . 192 ' ) within the excavation ( 220 ) at a first axial location between the distal end ( 152 ' ) and the end of the excavation ( 224 ) is greater than at a second axial location between the first axial location and the end of the cavity (FIG. 224 ). Rotor ( 56 ' ) according to any one of the preceding claims, wherein each pole finger ( 100 ' . 104 ' ) circumferentially opposed leading and trailing edges ( 156 . 160 ) and the associated excavation ( 220 ) between the leading and trailing edges ( 156 . 160 ) is arranged. Rotor ( 56 ' ) according to any one of the preceding claims, wherein at each pole finger ( 100 ' . 104 ' ) the excavation ( 220 ) has a width which is in a direction perpendicular to the axis ( 60 ), wherein the width at a first axial location between the distal end ( 152 ' ) and the end of the excavation ( 224 ) is greater than the width at a second axial location defined between the first axial location and the end of the cavity (FIG. 224 ). Rotor ( 56 ' ) according to any one of the preceding claims, wherein at each pole finger ( 100 ' . 104 ' ) the excavation ( 220 ) in an imaginary plane perpendicular to the axis ( 60 ) has a substantially triangular shape. Rotor ( 56 ' ) according to any one of the preceding claims, wherein at each pole finger ( 100 ' . 104 ' ) the excavation ( 220 ) in an imaginary plane parallel to the axis ( 60 ) has a substantially triangular shape. Rotor ( 56 ' ) according to any one of the preceding claims, wherein the end of the cavity ( 224 ) of each Polfingers ( 100 ' . 104 ' ) defines a vertex of the cavity. Rotor ( 56 ' ) according to any one of the preceding claims, wherein at each pole finger ( 100 ' . 104 ' ) at the associated end of the excavation ( 224 ) and the distal end ( 152 ' ) the radially inner surfaces ( 184 ' . 192 ' ) in places outside the excavation ( 220 ) Radially equal distance to the axis ( 60 ) to have. Rotor ( 56 ' ) according to one of claims 1 to 3, wherein each pole finger ( 100 ' . 104 ' ) a radially outer surface ( 180 . 188 ), the corresponding Polfinger ( 100 ' . 104 ' ) has a radial thickness between the radially inner surface ( 184 ' . 192 ' ) and the radially outer surface ( 180 . 188 ) and the radial thickness at a first location outside the cavity (FIG. 220 ) greater than at a second location within the cavity ( 220 ). Rotor ( 56 ' ) according to claim 10, wherein each pole finger ( 100 ' . 104 ' ) circumferentially opposed leading and trailing edges ( 156 . 160 ) and the first point in the circumferential direction between the cavity ( 220 ) and either the leading or the following edge ( 156 . 160 ) of the corresponding Polfingers ( 100 ' . 104 ' ). Rotor ( 56 ' ) according to claim 10 or 11, wherein the first location between the proximal end ( 148 ' ) and the end of the excavation ( 224 ) of the corresponding Polfingers ( 100 ' . 104 ' ). Rotor ( 56 ' ) according to any of claims 1 to 3, wherein each pole finger ( 100 ' . 104 ' ) circumferentially opposed leading and trailing edges ( 156 . 160 ) has the corresponding radially inner surface ( 184 ' . 192 ' ) in the circumferential direction between the leading edge and the following edge ( 156 ' . 160 ), and the leading and trailing edges ( 156 . 160 ' ) substantially parallel to the axis ( 60 ) are. Rotor ( 56 ' ) according to one of the preceding claims, wherein magnetically the first pole fingers ( 100 ' ) N are Polfinger and the second Polfinger ( 104 ' ) S Polfinger, and the rotor also at least one magnet ( 200 ' ) between a circumferentially adjacent pair of N and S pole fingers ( 100 ' . 104 ' ), the magnet ( 200 ' ) opposite N and S pole sides ( 216 ), and the magnetic N pole side ( 216N ) to the N-Polfinger ( 100 ' ) and the magnetic pole side ( 216S ) to the S Polfinger ( 104 ' ) couples. Rotor ( 56 ' ) according to any one of the preceding claims, wherein each pole finger ( 100 ' . 104 ' ) circumferentially opposed leading and trailing flank surfaces ( 164 ' . 168 '; 172 ' . 176 ' ) and the associated radially inner surface ( 184 ' . 192 ' ) in the circumferential direction between the leading and following flank surfaces ( 164 ' . 168 '; 172 ' . 176 ' ), and wherein the rotor further comprises at least one magnet ( 200 ' ) between the coupling leading and trailing edge surfaces ( 164 ' . 168 '; 172 ' . 176 ' ) of a pair of circumferentially adjacent first and second pole fingers (FIG. 100 ' . 104 ' ) is arranged and magnetically opposite Polseitenflächen ( 216 ), each magnetically opposite polar side surface ( 216 ) at either the leading or the following Polfinger flank surface ( 164 ' . 168 '; 172 ' . 176 ' ) substantially along the entire length of the corresponding Polfingers ( 100 ' . 104 ' ) between its proximal and distal ends ( 148 ' . 152 ' ) is present. Rotor ( 56 ' ) according to one of the preceding claims, additionally comprising an exciting coil ( 88 ) around the axis ( 60 ) around between the first and the second pole piece hub ( 92 . 96 ), wherein the N and S magnetic pole denominations of the first and second pole piece hub ( 92 . 96 ) selectively by a selected flow direction of the electrical current in the exciter coil ( 88 ). Rotating electrical machine ( 20 ' ) with: a rotor ( 56 ' ) according to one of the preceding claims, a stator ( 52 ' ), the rotor ( 56 ' ) and a housing ( 24 ) connected to the stator ( 52 ' ), wherein the rotor ( 56 ' ) of the housing ( 24 ) for rotation relative to the stator ( 52 ' ). Rotor ( 56 ' ) for a rotating electrical machine ( 20 ' ), the rotor ( 56 ' ) comprising: a pair of magnetic first and second pole pieces ( 44 ' . 48 ' ), each one hub ( 92 . 96 ), the first and second pole piece hubs ( 92 . 96 ) at a distance from each other along an axis ( 60 ) are arranged and a first and a second plurality Polfinger ( 100 ' . 104 ' ), the first and the second plurality of pole fingers ( 100 ' . 104 ' ) at a distance from each other about the axis ( 60 ) are arranged to define a substantially cylindrical outer rotor surface, each Polfinger ( 100 ' . 104 ' ) One Base ( 148 ' ), which on the first and the second pole piece hub ( 92 . 96 ) is mounted and towards the other pole piece hub ( 92 . 96 ), each Polfinger ( 100 ' . 104 ' ) of the first and second plurality of pole fingers ( 100 ' . 104 ' ) in a tip ( 192 ' ) ending between the bases ( 148 ' ) of a pair of pole fingers ( 100 ' . 104 ' ) of the other Polfingervielzahl ( 100 ' . 104 ' ), each Polfingerspitze ( 152 ' ) with a radially inwardly open cavity ( 220 ), which has a length which is in a direction axially inwardly of the tip ( 152 ' ) to the base ( 148 ' ) of the corresponding Polfingers ( 100 ' . 104 ' ) to the end of the excavation ( 224 ), wherein the cavity ( 220 ) a width extending between opposite flanks ( 156 . 160 ) of the corresponding Polfingers ( 100 ' . 104 ' ) in a direction substantially perpendicular to the axis ( 60 ), and a depth that extends substantially radially into the corresponding pole finger (FIG. 100 ' . 104 ' ), wherein at least one of these two dimensions of the cavity, namely width and depth, decreases along the cavity length in the direction axially inward. Rotor ( 56 ' ) according to claim 18, wherein the first pole fingers ( 100 ' ) magnetically N Polfinger and the second Polfinger ( 104 ' ) S Polfinger, wherein the rotor also has at least one magnet ( 200 ' ) between a circumferentially adjacent pair of N and S pole fingers (FIG. 100 ' . 104 ' ), the magnet ( 200 ' ) opposite N and S pole sides ( 216 ), the magnetic N pole side ( 216N ) to the N Polfinger ( 100 ' ) and the magnetic pole side ( 216S ) to the S Polfinger ( 104 ' ) couples. Rotating electrical machine ( 20 ' ) with: a rotor ( 56 ' ) according to claim 18 or 19, a stator ( 52 ' ), the rotor ( 56 ' ) and a housing ( 24 ) connected to the stator ( 52 ), wherein the rotor ( 56 ' ) of the housing ( 24 ) for rotation relative to the stator ( 52 ' ) is supported.

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