EP0604627A1

EP0604627A1 - Electric machine

Info

Publication number: EP0604627A1
Application number: EP93915960A
Authority: EP
Inventors: Frank Hillmann; Wolf-Rüdiger Canders; Harald Klein; Heinz Von Sothen; Eduard Wiegandt
Original assignee: Piller GmbH
Current assignee: Piller Group GmbH
Priority date: 1992-07-20
Filing date: 1993-07-20
Publication date: 1994-07-06
Also published as: JPH06511376A; WO1994002984A1; EP0604646A1; WO1994002986A1; KR940702660A; JPH06511378A; WO1994002985A1; EP0609410A1; JPH06511377A; DE4223831A1

Abstract

Une machine électrique comprend un rotor tournant autour d'un axe et un stator pourvu d'un jeu de plusieurs éléments polaires en C répartis autour de l'axe et situés à la même distance angulaire les uns des autres. Chaque élément polaire entoure un enroulement du stator avec une bande de base et avec deux doigts polaires qui font saillie sur celle-ci et génère une ligne de force du champ magnétique à peu près parallèle à un plan parmi un système de plans qui traverse l'axe. Afin d'obtenir une telle machine qui soit économique à produire tout en ayant une structure suffisamment stable, les éléments polaires sont insérés dans un évidement continu qui s'étend autour de l'axe dans le sens azimutal et y sont fixés au moyen d'une masse adhésive.An electric machine comprises a rotor rotating around an axis and a stator provided with a set of several C-shaped pole elements distributed around the axis and located at the same angular distance from each other. Each pole element surrounds a stator winding with a base strip and with two pole fingers which protrude from it and generate a line of force of the magnetic field roughly parallel to one plane among a system of planes that crosses the pole. axis. In order to obtain such a machine which is economical to produce while having a sufficiently stable structure, the pole elements are inserted into a continuous recess which extends around the axis in the azimuthal direction and are fixed there by means of an adhesive mass.

Description

DESCRIPTION

Electrical machine

The invention relates to an electrical machine, comprising a rotor rotating about an axis and a stator, which comprises a set with a plurality of C-shaped pole elements arranged at equal angular intervals around the axis, each of which has a base web and two of these protruding pole fingers encompasses a stator winding and generates a magnetic field line course which is aligned approximately parallel to a plane of a plane family passing through the axis.

Such electrical machines are known for example from DE-OS 35 36 538 or DE-QS 39 27 454.

However, the known solutions do not show any solutions that can be manufactured commercially.

The invention is therefore based on the object of creating an electrical machine of the generic type which can be produced inexpensively with a sufficiently stable construction.

This object is achieved according to the invention in an electrical machine of the type described in the introduction in that the pole elements are inserted as individual elements in a recess of a stator carrier which runs around the axis in the azimuthal direction and in that the pole elements are fixed in the recess by an adhesive. With this solution according to the invention, it is possible to produce the electrical machine of the generic type in a cost-effective manner with good stability and accuracy, since the recess is easy to make in the stator carrier and fixation of the pole elements by the adhesive also does not require any complex manufacturing steps.

Since the pole elements in the electrical machine according to the invention are preferably arranged with gaps to one another, it has proven to be particularly advantageous if the pole elements are fixed to one another in the azimuthal direction by base support elements lying between the base webs of the pole elements. The provision of such basic support elements has the great advantage that the pole elements can be stiffened with one another in the azimuthal direction.

Since, in the solution according to the invention, in particular, the forces acting on the pole elements due to the course of the magnetic field occur in the region of the pole fingers, it is also advantageous, alternatively or in addition to the solution described above, if the pole elements are arranged by fingers arranged between successive pole fingers support elements are supported against each other, the finger support elements in particular being arranged in the region of a front end of the pole fingers facing away from the base web. As a result, the pole elements are also supported in the azimuthal direction relative to one another, so that the pole elements together with the finger support elements form a unit that is stable in itself in the azimuthal direction. The provision of base support elements and / or finger support elements has a particularly advantageous effect on the anchoring of the pole elements in the stator carrier, since this anchoring only has to absorb part of the forces acting on the pole elements, since the other part by the base support elements and / or Finger support elements is intercepted. In particular when such support elements are provided, the fixing of the pole elements in the recess by means of the adhesive is sufficient for a stable construction of the electrical machine according to the invention.

No details have so far been given with regard to the design of the support elements.

An advantageous exemplary embodiment provides that each support element comprises a hardened casting compound. In the simplest case, the support elements are therefore made from a casting compound alone. Such a casting compound is, for example, a polymer compound, such as polymer concrete, or a resin, such as casting resin or trickling resin. As an alternative to this, the casting compound can also be, for example, a metal alloy, preferably a low-melting metal alloy, for example a bismuth alloy, which is introduced into the interspaces between the individual pole elements.

In particular when a potting compound is provided, it has proven to be advantageous if each supporting element has an interposed space between the pole elements and is penetrated by the potting compound in the flowable state Has holding body. Such a holding body offers the advantage that the potting compound is received and held by the holding body in the flowable state, that is to say it is prevented from continuing to flow.

The holding body is preferably porous. It is also advantageous if the holding body is elastic and can therefore be fitted exactly into the spaces between the pole elements.

A particularly advantageous solution provides for the holding body to be made of fiber material, in particular of felt. In the case of such a holding body, the holding body is preferably stiffened with a casting resin or a trickling resin as a potting compound.

In the arrangement of the support elements, it is also advantageous if they are positively secured against movement in the radial direction on the pole elements. This can be achieved, for example, by a projection formed from the casting compound, which engages in a recess in the pole elements.

With regard to the design of the recess, no further details have been given in connection with the previous explanation of the advantageous exemplary embodiment.

An advantageous type of recess provides that it has two side walls which extend in the azimuthal direction to the axis and face one another, between which is the potting compound. Such a type of recess makes it easier, on the one hand, to introduce the potting compound and, on the other hand, stabilize the potting compound.

In such an embodiment it is preferably provided that the pole elements sit between the side walls of the recess and are fixed by them against movement transverse to the azimuthal direction. This type of formation of the recess creates additional stiffening and advantageous support of the pole elements against forces acting in the radial direction of the axis, so that these forces do not have to be absorbed by the support elements, for example.

The recess could in principle be defined by the two side walls. However, it is even more advantageous if the recess has a bottom which extends between the side walls and which also serves to accommodate the casting compound between itself and the side walls.

A particularly stable version of the solution according to the invention provides that the pole elements sit with their base web on the floor, so that the floor forms an additional support against forces acting in the axial direction and additionally a support against tilting forces when the pole elements with their base webs lie fully on the floor.

In connection with the previous explanation of the solution according to the invention, it was only assumed that the pole elements in the recess a potting compound serving as an adhesive are fixed. Such a potting compound creates the additional advantage of fixing the pole elements as stiffly as possible in the recess.

It is particularly expedient if the pole elements are embedded with their base web in the potting compound which essentially fills the recess. This ensures a particularly rigid fixation of the pole elements in the stator carrier.

In order to fix the pole elements aligned in the stator carrier in precisely defined positions, in particular precisely defined angular distances, and in particular to keep them in the positions provided for them, it is provided in addition or as an alternative to the previously described exemplary embodiments that the pole element is positioned rings are held aligned on the stator carrier at equal angular intervals.

Such positioning rings can be parts of the stator carrier on the one hand. However, it is particularly advantageous if the positioning rings can be mounted on the stator carrier, so that the positioning rings can be manufactured independently of the stator carrier and the recess in the stator carrier and these are subsequently mounted on the stator carrier.

A clear alignment of the pole elements by means of the positioning rings can in particular advantageously be achieved in that the positioning rings of each pole element Fix in the azimuthal direction between two projections. This represents the structurally simplest and, in particular, also the most technically economical solution for the formation of the positioning rings.

In the simplest case it could be sufficient if a positioning ring is provided, but it is even more advantageous if two positioning rings are arranged at a distance from one another.

The positioning rings have a particularly useful effect if they are arranged on opposite sides of the recess.

With regard to the alignment and design of the pole fingers, no further details have been given in connection with the previous explanation of individual advantageous exemplary embodiments. For example, in the context of the solution according to the invention it is conceivable to arrange the pole fingers in accordance with the teaching of DE-OS 35 36 538 or DE-OS 39 27 454. However, it is even more advantageous if the pole fingers extend approximately parallel to the axis.

In this case, a solution which is favorable in terms of assembly and later stability provides that the pole elements are inserted into the recess in the direction parallel to the axis.

Structurally particularly simple manufacturing conditions arise when the side walls of the recess open Cylinder surfaces lie to the axis, which on the one hand enable precise radial positioning of the pole elements and on the other hand are easy to manufacture.

Furthermore, it is advantageously provided that the bottom of the recess lies in one plane, the plane extending in particular transversely to the axis.

With regard to the size and the force effect, there are particularly advantageous conditions if the stator carrier extends in the radial direction to the axis and has the recess.

The stator carrier is expediently designed in such a way that it forms a bearing plate for mounting the rotor, so that, in turn, a defined orientation of the pole elements relative to the rotor is ensured, which is in particular less sensitive to deformation and ensures high rigidity , so that on the other hand an air gap between the rotor and the pole elements can be kept relatively small.

It has also proven to be particularly expedient if the end shields forming the stator carrier are part of a housing and are in particular stabilized relative to one another by a housing shell extending between the end shields. This is in addition to the stable and rigid arrangement of the pole elements At the same time, a housing for the electrical machine according to the invention has been created, so that this solution offers particular advantages in terms of cost-effective manufacture.

In connection with the previous explanation of a single exemplary embodiment, it was always assumed that at least one set of pole elements is provided; It is particularly advantageous with regard to a higher torque if several sets of pole elements are provided.

This can be implemented in a structurally simple manner particularly when the pole fingers of the pole elements from different sets extend parallel to one another.

An advantageous exemplary embodiment of an electrical machine according to the invention provides that in each case a set of pole elements is arranged on opposing stator carriers and in particular that the pole fingers are directed towards one another.

It is even more advantageous, in particular to achieve the greatest possible torque, if the pole elements are E-shaped, so that one set of E-shaped pole elements comprises two sets of C-shaped pole elements.

With regard to the construction of the pole elements, none in connection with the previous exemplary embodiment details given. An advantageous exemplary embodiment provides that the pole elements are constructed from laminated cores, the laminated cores preferably having laminations stacked in the azimuth direction.

With regard to the cost-effective manufacture of the laminated cores, it is particularly expedient if the laminated cores are constructed from a predetermined number of uniform sheets, i.e. that each laminated core has the same number of identical sheets.

The metal sheets themselves can comprise conventional soft iron material used for electrical machines.

An advantageous alternative is the use of sheets made of metallic glasses, since in the present case these have more advantageous properties.

As an alternative to constructing the pole elements from sheet metal, another solution according to the invention provides that the pole elements are made from iron powder, i.e. that the entire body of the pole elements is made from iron powder.

Alternatively, a further embodiment provides that the pole elements are made of a sintered material.

In the previous description of individual advantageous exemplary embodiments, it was no longer considered how the recess should be arranged in the stator carrier. An advantageous exemplary embodiment provides that the stator carrier is an inherently rigid part which carries the pole elements via a mechanically rigid connection, such as, for example, the casting compound.

With regard to the transmission of vibrations, however, it is particularly advantageous if the pole elements are mounted elastically. This is possible, for example, by elastic anchoring of the pole elements on the stator carrier.

However, it is even more advantageous if the recess receiving the pole elements is arranged in a retaining ring and the retaining ring is elastically mounted on a stator stand. Thus, a set of pole elements together with the retaining ring rotating around the axis form a unit which is rigid in itself and this unit which is rigid in itself is elastically mounted on the stator stand. The elastic mounting is sufficient to dampen the vibrations occurring in the area of the pole elements and to pass them on to the stator carrier as little as possible. On the other hand, the inherently rigid unit consisting of pole elements and retaining ring has the advantage that the pole elements themselves are fixed with sufficient rigidity and the elastic connection to the stator with the stator carrier does not lead to excessive mobility of the pole elements, which in turn has the disadvantage that that an air gap between the pole elements and the rotor would have to be increased taking into account the mobility of the pole elements. A particularly advantageous fixation of the retaining ring on the stator stand is given if the retaining ring is supported on two opposite sides by elastic elements on the stator stand, so that a sufficiently rigid connection between the retaining ring and the stator stand takes place despite elastic support.

A particularly advantageous exemplary embodiment provides that the retaining ring is held elastically between two bearing walls extending in the shape of a cylinder jacket or a cone jacket around the axis.

Another expedient embodiment provides that the retaining ring is elastically supported in a bearing recess in the stator stand.

For example, rubber rings are provided as elastic elements, which are glued to the retaining ring and the stator carrier or are vulcanized onto corresponding surfaces.

No details have so far been given with regard to the formation of the rotor and the formation of magnetic circuit elements of the rotor. It would be conceivable, for example, if the pole elements with their pole fingers point to the magnetic circuit elements of the rotor, as is the case, for example, with the magnetic circuit elements according to DE-OS 39 27 454. However, it is even more advantageous if a free pole slot section is arranged between the pole fingers of the pole elements following the stator winding, in which magnetic circuit elements of the rotor can be successively positioned.

Such an arrangement of the magnetic circuit elements of the rotor has the advantage that the magnetic circuit elements act on the rotor with the smallest possible moments transversely to a rotary movement of the rotor.

With regard to the design of the magnetic circuit elements, different variants are also conceivable. For example, it is conceivable to produce the magnetic circuit elements from iron powder or a sintered material or a ferro-ceramic.

An advantageous variant provides that the magnetic circuit elements of the rotor are designed in the form of laminated cores.

The laminated cores are preferably designed such that they have laminations stacked in the direction of the axis of the rotor.

Such sheets are preferably conventional soft iron sheets used in electric motor construction.

On the other hand, due to the arrangement of the magnetic circuit elements between the pole fingers and the resulting small size, it is conceivable to use metallic glasses as sheets. All of the sheets in the packages are preferably insulated from one another.

With regard to the arrangement of the magnetic circuit elements on the rotor, no further details have likewise been given in connection with the previous explanation of individual exemplary embodiments.

The magnetic circuit elements could, for example, be formed by a continuous circumferential ring which is closed about the axis of the rotor, in which case a magnetic asymmetry between the successive magnetic circuit elements is created by an enlarged air gap between them.

However, it is particularly advantageous if the rotor has a multiplicity of individual magnetic circuit elements which can be penetrated by the magnetic field line profile of the poles, and which follow one another in the azimuthal direction, the number of magnetic circuit elements of a set corresponding in particular to the number of pole elements of the corresponding set.

The provision of individual magnetic circuit elements in contrast to a closed ring made of a uniform material rotating around the axis is to be seen in the fact that on the one hand these are material-saving in terms of the expensive material required for the magnetic circuit elements and on the other hand there is the possibility of controlling thermal expansion more easily. When individual magnetic circuit elements are provided, it is particularly advantageous if there is a gap with respect to the magnetic conductivity between successive magnetic circuit elements. This solution allows a maximum variation of the magnetic conductivity between successive magnetic circuit elements and thus an optimization of the function of the electrical machine according to the invention.

It is particularly expedient if the gap in the azimuthal direction has an extent which is at least half the extent of one of the magnetic circuit elements in the azimuthal direction.

Another advantageous exemplary embodiment provides that intermediate pieces are arranged in the gaps between the magnetic circuit elements.

In order to suppress the stray field as much as possible in the gaps between successive magnetic circuit elements, it is preferably provided that the intermediate pieces are made from a stray field shielding material. This is preferably a highly electrically conductive material which suppresses the stray field in the region of the gaps by the formation of eddy currents.

Furthermore, the intermediate pieces are advantageously made of a material with high electrical conductivity in order to achieve that through the stray field in the intermediate pieces Eddy currents are achieved with the lowest possible losses, which lead to a desired further damping of the stray field.

The intermediate pieces are preferably made of a magnetically non-conductive material in order to achieve the greatest possible fluctuation in the magnetic conductance between the intermediate pieces and the magnetic circuit elements.

The intermediate pieces are expediently shaped such that they bear in a form-fitting manner on the magnetic circuit elements and thus fix the magnetic circuit elements in a form-fitting manner on the rotor.

It is particularly advantageous if the intermediate pieces fix a central area of the magnetic circuit elements in a form-fitting manner and thus the magnetic circuit elements extend beyond the intermediate pieces in a radial direction. A particularly expedient solution provides that the intermediate pieces also fix the magnetic circuit elements positively against rotation about an axis parallel to the axis of the rotor.

With regard to the arrangement of the magnetic circuit elements and the intermediate pieces, no further details have so far been given either.

An advantageous exemplary embodiment provides that the intermediate pieces sit on a rotor body carrying the magnetic circuit elements. The intermediate pieces could in turn be connected to the rotor ring by connecting elements. However, it is even more advantageous if the intermediate pieces are integrally formed on the rotor body.

So far nothing has been said about the cooling of the magnetic circuit elements. A particularly good cooling effect of the magnetic circuit elements can be achieved if the intermediate pieces are thermally coupled to the magnetic circuit elements. In the simplest case, this is done by pouring gaps between the intermediate pieces and the magnetic circuit elements, for example with a casting compound.

With regard to the design of the intermediate pieces relative to the magnetic circuit elements, no further details have been given.

It is preferably provided that the intermediate pieces extend in the direction of the magnetic circuit elements over the same distance as the magnetic circuit elements. The magnetic circuit elements preferably extend in a direction parallel to the axis of the rotor, so that the intermediate pieces between the magnetic circuit elements also extend in this direction.

No details have so far been given regarding the training of the runner.

An advantageous exemplary embodiment provides that the rotor encompasses a rotor disk carrying the rotor ring. In particular in the case of pole elements arranged on opposite sides of the rotor, it is provided that the rotor disk carries a rotor ring on opposite sides.

In the context of the previous description of individual exemplary embodiments, the primary focus was on how an electrical machine works with a single set of C-shaped pole elements and associated magnetic circuit elements. However, it is particularly advantageous, in particular with regard to the greatest possible output and the most uniform torque possible, if the electrical machine comprises a plurality of motor units, each with a set of C-shaped pole elements and a set of magnetic circuit elements associated therewith.

It is particularly advantageous with regard to a concentricity which is as uniform as possible if the pole elements and the magnetic circuit elements of different motor units are arranged in the electrical machine in such a way that the motor units form a sequence of motor units which operate with a constant phase shift between successive motor units, which means that there is a phase shift between every two successive motor units, which corresponds to 2TT divided by the number of motor units of the electrical machine.

Structural advantages with regard to the construction of such an electrical machine result when the magnetic circuit elements of different motor units are attached the rotor are arranged with an angular offset relative to one another, since this allows the C-shaped pole elements associated with these magnetic circuit elements to be arranged in one plane. This means that, for example, the pole elements of different motor units sitting on one side of the rotor are each arranged in the same planes and the magnetic circuit elements assigned to these different motor units are then held on the rotor with a corresponding offset.

With regard to the design of the stator winding, no further detailed information has been given in connection with the exemplary embodiments described so far.

An advantageous exemplary embodiment provides for the stator winding to comprise a coil ring which extends around the axis and is arranged coaxially to the latter and around which the C-shaped pole elements each engage.

The magnetic circuit elements could, for example, also be permanent magnets. However, magnetic circuit elements that are made of a non-permanently magnetized and magnetically conductive material are particularly advantageous.

Particularly when the electrical machine is operating as a reluctance motor, it is advantageously provided that the stator winding has a current flowing through it with an AC component and a current with a DC component. A particularly preferred embodiment of the electrical machine according to the invention works as a synchronous motor, in particular as a modified reluctance motor, in which the number of pole elements of a set corresponds to the number of magnetic circuit elements assigned to this set of pole elements and all magnetic circuit elements are attracted to the pole elements or not at the same time get dressed by.

The basic design of the electrically excited transverse flux machines, for example encompassed by the invention, is known from DE 39 27 454 C2.

Such synchronous machines are used in particular where a high force density per unit volume and low losses are required. Essential features of such transverse flux machines are the design of the winding in the form of ring coils concentric to the shaft and the magnetic circuits arranged transversely around the coil.

In the solution known from DE 39 27 454, the magnetic flux is guided in soft iron pole elements which are arranged perpendicular to the direction of movement, the winding with its magnetizing parts running in the longitudinal direction and being divided into two coil parts, one of which is in one a direct current and an alternating current in the other. The magnetic circuits formed by the soft iron pole elements should always include both coil parts. Numerous problems arise in practical implementation, in particular with regard to a compact design with a high force density. The solution according to the invention is based on the consideration of optimizing the pole geometry of the machine in the sense of increasing the force density, based on the machine volume.

In this sense, the invention in its most general embodiment provides an electrically excited transverse flux machine with a movable and a fixed part (rotor; stator) with the following features:

the stator has a number of pole elements aligned radially to the shaft of the machine, which are arranged uniformly distributed in the circumferential direction, each pole element is designed with at least one pole groove extending in the direction of the axis of the rotor, each pole element, for example , starting from a central pole section, in the direction of two end-side bearing plates of the machine is formed in mirror image, in the pole groove runs at least one excitation coil arranged concentrically to the shaft, the rotor guided on roller bearings comprises at least one, in particular two carrier disks, each with ¬ because at least one rotor ring running concentrically to the shaft is fitted, which engages in the corresponding pole groove in the stator. This structure enables the arrangement of the soft iron pole elements in a uniform distribution and radial alignment in a very small space, and the corresponding design of the rotor rings enables a high force density with a small mass.

This can be further optimized if, according to one embodiment, the pole elements, starting from the central pole section, are each formed with three pole fingers on each side (mirror image), with simultaneous formation of two pole grooves each concentric to the axis Page.

In the side view, the individual pole piece thus has the shape of a double "E", the two "E" being arranged in mirror image to one another.

If, for example, two excitation coils are inserted in the pole grooves (two on each side), this corresponds to the integral design of four motors, with the corresponding coils being actuated offset. The result is extremely smooth machine operation with minimal losses.

The excitation coils can be coils wound from copper wire.

Starting from, for example, 64 pole elements arranged symmetrically to the shaft axis, each with three pole fingers on each side, there are 128 sections of the pole elements on each side which are to be insulated from the respective excitation coil. To solve this structurally and electrically complicated problem, one embodiment of the invention provides for the insulation between the excitation coils and the pole faces of the corresponding pole fingers to be formed by U-shaped insulating bodies or groove linings that are open in the direction of the end shields.

The individual insulating pieces or groove designs can preferably be discrete components, but this requires a corresponding outlay on equipment. According to an advantageous embodiment of the invention, the base sections of the U-shaped bent-up insulating bodies should therefore be integrally connected to one another between adjacent pole elements.

This results in the possibility of isolating all contact surfaces between the excitation coil and the pole elements with a single insulating body or a single slot formation per pole slot. The insulating body can be a stamped insulating paper, which then has a central, annular, closed base, from which radially outward and inward leg sections run which are later bent up.

With the help of a single tool, such an insulating body can be used in one work step.

A further development provides for the free ends of the U-legs of each insulating body section to be cranked outwards, the cranked section then can snap into corresponding slots on the surfaces of the pole fingers. In this way, an anti-rotation lock is achieved at the same time.

It is particularly advantageous if the excitation coils are covered on the top by insulating pieces attached to the pole fingers.

The slots for the insulating bodies can also be used to fix insulating pieces which are placed on the top of the excitation coils, in particular if the excitation coil is made in several parts per pole slot, so that the individual partial windings are separated from one another by the insulating pieces mentioned.

The electrical connection elements of the windings can be brought out radially between the pole pieces.

The pole elements are preferably made of soft iron and are each formed, for example, from a large number of laminated sheets. Electrical baked enamel sheets have proven to be particularly advantageous.

For the assembly of the individual pole elements (which - viewed in the direction of the axis of the rotor - corresponds approximately to the minute division of a clock), the application of a shrink ring has proven to be advantageous. A corresponding inner ring can prevent the deformation of the pole elements. Basically, a shrink ring, which then preferably runs on the peripheral surface of the central pole sections, is sufficient for the assembly. Likewise, however, the pole fingers projecting on both sides can also be surrounded on the circumference by their own shrink rings. Such shrink rings can be expanded, for example, by inductive heating and then applied in a stationary manner by cooling to the peripheral surface.

With regard to a necessary cooling of the machine, the shrink rings can be formed simultaneously with cooling fins or grooves for the passage of cooling air.

Structural advantages result when the pole pieces and the excitation coils lying in the pole grooves are cast with an insulating resin.

It is particularly expedient if the rotor rings are formed on the circumference with corresponding groove-like depressions in accordance with the positioning of the pole pieces.

It is also expedient if at least one excitation coil is located in each of the pole slots.

In addition, it is preferably provided that the excitation coil of each pole slot is divided into two partial coils arranged one above the other (viewed in the direction of the axis). Further features and advantages of the solution according to the invention are the subject of the following description and the drawing of some exemplary embodiments. The drawing shows:

1 shows a longitudinal section through an electrical machine according to the invention.

FIG. 2 is a sector-by-section representation of a plan view in the direction of arrow A in FIG. 1, with the right stator broken away at the top left and additionally the rotor broken away at the top right;

FIG. 3 shows an enlarged, fragmentary, plan view of a pole element in a view similar to FIG. 1;

4 shows an enlarged detail; Top view of several pole elements in a view similar to Figure 2 top right.

5 shows an enlarged illustration of a plan view of a plurality of pole elements in the direction of arrow B in FIGS. 1 and 2;

FIG. 6 shows an enlarged illustration of a pole element similar to FIG. 3 with support elements;

7 shows a cross section through a rotor in a view similar to FIG. 1. FIG. 8 is an enlarged partial illustration of the rotor along line VIII-VIII in FIG. 9;

FIG. 9 is an enlarged, fragmentary illustration of a plan view of the rotor in the direction of arrow D in FIG. 7;

FIG. 10 shows an enlarged detail, illustration of a second exemplary embodiment in a view similar to FIG. 6;

11 shows a partial section through a third exemplary embodiment of a machine according to the invention;

FIG. 12 shows a plan view of a partial segment of an insulating body for use in the machine according to FIG. 11;

13 the insulating body according to FIG. 12, in the assembly position (in section) and

14 is a plan view of an inner surface of a rotor of the machine according to FIG. 11.

A first exemplary embodiment of an electrical machine according to the invention comprises, as shown in FIG. 1, a housing 10 in which a rotor 12 is mounted so as to rotate about an axis 14. For this purpose, the rotor 12 has a rotor shaft 16, which is arranged in two rotor bearings 18 and 20 arranged at a distance from one another in a front Bearing plate 22 or a rear bearing plate 24 of the housing 10 is mounted. The front end plates 22 and 24 carry a housing jacket 26 which extends between the end plates 22 and 24 and closes an interior 28 of the housing together with the end plates 22 and 24 to the outside.

The end shields 22 and 24 simultaneously represent stator carriers for two stators 30 and 32, each of which, as shown in particular in FIG. 2, a set with a plurality of circumferentially around the axis 14 at equal angular distances and equal radial distances from the Axis 14 arranged pole elements 34 includes.

As shown in FIG. 3, each of the pole elements 34 comprises a base web 36, from which three pole fingers 38, 40 and 42 extend parallel to one another, with a pole groove between each of two pole fingers 38 and 40 and 40 and 42 44 or 46 lies, so that overall the pole element has an E-like shape, which can also be referred to as double-C, the pole fingers 38 and 40 with the base web 36 and the pole fingers 40 and 42 with the base web 36 form a C-shape.

In the pole grooves 44 and 46, namely in a rear groove section 48 or 50 of the pole groove 44 or 46, which extends from a groove bottom 52 or 54, there is one as a whole in each of the pole grooves 44 and 46 designated 56 and 58 stator winding. Each of the stator windings 56 and 58 runs coaxially to the axis 14 on an annular path perpendicular to the axis 14, but at a different distance from the axis 14. In the exemplary embodiment shown in FIG. 3, the two stator windings 56 and 58 are further divided into two partial windings 56a and b and 58a and b, the two partial windings 56a, b and 58a, b being separated from one another by a spacer finger 60 and 62, respectively are. The spacer fingers 60 and 62 are integrally formed on the base web 36 of the pole element 34 and rise approximately centrally from the respective groove bottom 52 and 54, respectively.

It engages in a front slot section 64 or 66 which adjoins the rear slot section 48 or 50 and which extends from the stator windings 56 or 58 to the front ends 68, 70, 72 of the pole fingers 38, 40, 42 Runner 12 with its magnetic circuit elements 74 and 76, respectively, in order to permit a closed magnetic field line profile 78 or 80 respectively in the magnetic circuit element 74 or 76 standing in the front groove section 64 or 66, the magnetic field line profile 78 through the base web 36 as well as the pole fingers 38 and 40 and the magnetic circuit element 74 and the air gaps between the latter and the pole fingers 38 and 40, while the magnetic field line course 80 runs through the base web 36 and the pole fingers 40 and 42, the magnetic circuit element 76 and the air gaps between the latter and the pole fingers 40 and 42 passes through.

The magnetic field line courses 78 and 80 of the pole elements 34 preferably lie in planes of a set of planes which passes through and is defined by the axis 14. For anchoring to the respective stator carrier, that is to say to the front bearing plate 22 and the rear bearing plate 24, the pole elements 34 are inserted into a recess 82 in the stator carriers 22, 24, this recess 82 preferably being formed as an annular groove concentric with the axis 14 , whose inner side wall 84 and outer side wall 86 are each part of a cylindrical surface coaxial with the axis 14 and whose bottom 88 is formed by an annular surface concentric with the axis 14, which is perpendicular to the axis 14.

The recess 82 is designed such that the pole elements 34 lie with a substantial part of their base web 36 in the recess 82, sit on the base 88 with a base surface 90 and with their outer sides 92 and 94, which are in outer sides 92 and 94 the pole fingers 38 and 42 pass over, bear against the inner side wall 84 and the outer side wall 86 and are thus positively secured against movement radially to the axis 14 by the recess 82.

To fix the pole elements in such a way that their mutually facing surfaces 96 and 98 also extend approximately parallel to planes of a plane group passing through and defined by the axis 14 and the pole elements 34 at equal angular distances around the axis 14 an inner positioning ring 100 is provided on a radially inner side of the pole elements 34 and an outer positioning ring 102 is provided on a radially outer side of the pole elements 34, each of the positioning rings 100, 102 having projections 104 and 106, respectively , Which engage between mutually facing surfaces 96, 98 of successive pole elements 34 and rest on these surfaces 96, 98 of successive pole elements 34 and thus exactly define the distance between these pole elements.

These positioning rings 100 and 102 can preferably be fixed to the respective stator carrier 22 or 24 by fastening elements 108 and 110, so that advantageous positioning of the positioning rings 100 and 102 is possible, which is separate from the stator carrier and has a more dimensioned manufacture Projections 104 and 106 relieved. These positioning rings 100 and 102 can thus be retrofitted to the stator carriers 22 and 24 which are produced separately with the recess 82.

In addition to the alignment of the pole elements 34 at defined angular intervals around the axis 14, the pole elements 34 are stabilized relative to one another in the azimuthal direction 112 by base support elements 114 lying in the recess 82 on the one hand, which base bases 36 of the pole elements 34 lie opposite one another Fill in surfaces 96 and 98. In the simplest case, the base support elements 114 are formed by a potting compound which fills the recess 82 and, after they have hardened, forms the base support elements lying between the surfaces 96 and 98 of the pole elements 34 in the region of the base webs 36. At the same time, the potting compound causes the areas of the base webs 36 lying in the recess 82 to be glued on all sides to the side walls 84 and 86 and the bottom 88 thereof. An even more advantageous alternative of base support elements, shown in FIGS. 5 and 6, comprises a holding body 116 made of elastic and porous material, for example felt, which in the spaces between the surfaces 96 and 98 in the region of the base webs 36 into the recess 82 is inserted and impregnated with a sealing compound 118, which on the one hand passes through the holding body 116 and at the same time also penetrates into the spaces between the pole elements 34 and the recess 82, so that after hardening the porous and elastic holding body stiffens on the one hand and on the other hand the pole element 34 is also glued into the recess 82 with its outer sides 92 and 94 and the base surface 90.

The holding body 116 has the advantage that it absorbs the casting compound 118 and thus also holds it in the uncured state and prevents it from flowing away.

In addition, for additional stiffening between the pole elements 34 in the region of the pole fingers 38, 40 and 42, finger support elements 120 are provided, which likewise comprise a holding body 122 made of porous and elastic material, for example also felt, which in turn is stiffened by a sealing compound 124 . The holding body 122 has the great advantage that it also keeps the potting compound 124 in the uncured state and prevents it from flowing away.

The finger support elements 120 preferably sit in the region near the ends 68, 70 and 72 of the pole fingers 38, 40 and 42 and likewise lead to a stiffening between the pole elements 34 in the direction of the azimuthal direction 112. For better fixation on the pole elements 34, the finger support elements 120 engage in recesses 117 in the pole elements 34 with projections 119, the projections 119 passing through the casting compound 124, which emerges from the holding body 122 in the region of the recesses 117 , form the.

The rotor designated as a whole as 12 includes, as shown in FIG. 7, in addition to the rotor shaft 16, a rotor disk 130 extending radially to the latter and in a plane 132 perpendicular to the axis 14. This rotor disk carries in a radially outer region 7 and 8, on both sides of the air circulation blades 134 and 136 extending away from the same in the direction of the axis 14, which in turn carry rotor rings 138 and 140, respectively, with their ends facing away from the rotor disk 130, from which the magnets circular elements 74 and 76 also extend in the direction parallel to the axis 14.

8 and 9, the magnetic circuit elements 74 and 76 sit between teeth 142 and 144 which are integrally formed on the rotor rings 138 and 140 and which encompass the magnetic circuit elements 74 and 76 in a central region 146 in a form-fitting manner on both sides.

The magnetic circuit elements 74 and 76 have radially inner projections 148 and radially outer projections 150, which pass through a central region 146 are connected, which in turn has an outer contour 152 which extends transversely to the radial direction from one projection 148 to the other projection 150 and bulges and narrows transversely to the radial direction, this outer contour 152 having, for example, the shape of a circular cylinder segment.

The bulging and narrowing outer contour 152 is encompassed by the teeth 142 on both sides of each magnetic circuit element 74, 76 and thus leads to a positive fixation of the magnetic circuit elements 74 and 76 both against movement in the radial direction and in the azimuthal direction and additionally against rotation about an axis parallel to axis 14.

Magnetic circuit elements 74, 76 are preferably provided with central regions 146 of holes 154 penetrating them and extending parallel to axis 14, through which fastening screws 156 pass, which in turn are screwed into rotor rings 138 and 140, so that screws 156 the magnetic circuit elements 74, 76 bear against the rotor rings 138 and 140 and hold them fixed between the teeth 142, 144 against movement in the direction parallel to the axis 14.

The teeth 142 and 144 extend from the rotor rings 138 and 140 in the direction parallel to the axis 14 over the same distance as the magnetic circuit elements 74, so that the rotor 12 in the region of the magnetic circuit elements 74 and 76 continuously runs in a plane around the side circular ring elements faces 160 and 162. However, the teeth 142 and 144 extend in the radial direction only to such an extent that they engage positively around the central region 146 of the magnetic circuit elements 74 and 76, so that the magnetic circuit elements 74, 76 with their radially inner projections 148 project beyond an inner side 164 and with their radially outer projections 150 over an outer side 166.

The teeth 142 and 144 are preferably formed in one piece on the rotor rings 138 and 140 and are made of a magnetically nonconductive, but electrically good conductive material, such as aluminum.

For optimum fixation, gaps 168 which form between the magnetic circuit elements 74 and 76 and the teeth 142 and 144 are cast with an impregnating resin in order to obtain a thermally optimal coupling between the teeth 142, 144 and the magnetic circuit elements 74, 76.

As shown in FIG. 6, all the pole elements 34 with their pole fingers 38 and 40 and the part of the base web 36 connecting them form a set of C-shaped pole elements which is arranged around the axis 14. All magnetic circuit elements 74 interact with this set of C-shaped pole elements, the number of magnetic circuit elements 74 corresponding to the number of C-shaped pole elements. For example, 64 C-shaped pole elements and 64 magnetic circuit elements 74 are provided.

These C-shaped pole elements formed from the pole fingers 38 and 40 and the base web 36 together with the stator winding 56 and the magnetic circuit elements 74 form a Motor unit 170, which runs as a synchronous motor and in which all magnetic circuit elements 74 are always attracted or not attracted simultaneously by the C-shaped pole elements (FIGS. 1 and 6).

In the same way, the pole fingers 40 and 42 together with the corresponding section of the base web 36 form a set of C-shaped pole elements arranged around the axis 14 and with the stator winding 58 and the magnetic circuit elements 76 a further motor unit 172, which in the same Way works like motor unit 170.

The magnetic circuit ^elements' 76, however, are compared with the magnetic circuit members 74, as is apparent in particular from Fig. 2, offset at an angle distance from each other arranged an¬ which is selected so that the magnetic circuit elements 74 then elements exactly in their associated C-shaped pole stand when the magnetic circuit elements 76 stand exactly in the middle between the C-shaped poles associated therewith. This means that the angular offset of the arrangement of the pole elements 74 relative to the pole elements 76 corresponds to a phase offset of 2TT / 2.

The magnetic circuit elements 74 and 76, which protrude from the rotor 12 on the opposite side thereof, also form motor units 174, 176 with parts of the pole elements 34 of the stator 32, so that the electrical machine according to the invention has a total of four motor units 170, 172 , 174, 176, which all work out of phase with one another and form a sequence 170, 174, 172, 176 in which each of the motor units is opposite the other has a phase shift of 2TT / 4. This achieves an extremely uniform concentricity of the electrical machine according to the invention with low losses at the same time (FIG. 1).

The pole elements 34 can in principle be made in one piece from sintered material or iron powder. A particularly advantageous construction of the pole elements 34 from individual sheets 180, which are insulated from one another and run parallel to the surfaces 96, 98. These sheets are particularly E-shaped. For example, these individual sheets are lacquered electrical baking sheets.

Such a pole element 34 thus represents a laminated core of laminations 180 lying against one another, which are stacked on top of one another in the azimuthal direction 112 and extend parallel to the surfaces 96, 98. These sheets are preferably electric baked enamel sheets, but alternatively it is also conceivable to form these sheets from metallic glasses.

In the same way, the magnetic circuit elements 74 and 76 are either made in one piece from iron powder or likewise as laminated cores, which, as shown in FIG 184 exist. These sheets are, for example, also electrical baked enamel sheets. Due to the small size of the magnetic circuit elements 74, 76, it is also possible, for example, to use sheets made of metallic glasses as sheets 184. In a second exemplary embodiment, shown in FIG. 10, the recess 82 is not arranged in the respective end shield 22, 24, as shown in FIG. 1, but the recess 82 lies in a retaining ring 190, which in turn is concentric with the Axis 14 extends around it and is supported in a bearing recess 192 in a stator stand of the respective end shield 22 or 24. The bearing recess 192 comprises an inner bearing wall 194 and outer bearing wall 196, both of which preferably have a cylindrical shape with respect to the axis 14. In these, the retaining ring 190 is arranged such that an inner outer wall 198 and an outer outer wall 200 extend at a distance from the respective bearing wall 194 and 196, respectively. An intermediate space located between the respective bearing wall 194 or 196 and the respectively opposite outer wall 198 or 200 is filled by an elastic intermediate layer 202 or 204, which is on the one hand on the bearing wall 194 or 196 and on the other hand on the respective outer wall 198 or 200 supports, holds the retaining ring 190 and is aligned so that the pole fingers 38, 40, 42 each extend parallel to the axis 14.

In order to obtain the most effective cooling of the pole elements 34, an intermediate space 210, through which a cooling medium flows, is preferably provided between a recess bottom 206 of the bearing recess 192 and a rear side 208 of the retaining ring 190. The space 210 is expediently divided by partitions 212, so that a defined space 210 is formed in this space Management of a cooling medium is possible. The intermediate walls 212 rise from the recess base 206 and extend to the rear side 208, the rear side 208 standing at a short distance from these intermediate walls 212 or an elastic material which the intermediate spaces 210 is arranged between the rear side 208 and the intermediate walls 212 seals against each other.

The intermediate layers 202 and 204 are preferably made of glued-in or vulcanized-in rubber rings, wherein, for example, either one or more O-rings are used as rubber rings. In the following figures, identical or equivalent components are identified with the same reference numerals.

In a third exemplary embodiment, shown in FIG. 11, “W” denotes the axis of a rotor shaft (not shown) of a rotor of an electrical machine according to the invention.

A total of 64 pole elements 310 are provided radially to the axis W of a rotor shaft. Each pole piece 310 consists of a plurality of electro-baked enamel sheets arranged one on top of the other and has the following shape: a central pole section 310m, from which - in the direction of the axis W - three pole fingers 310f run on both sides, which are between them correspondingly form two pole grooves 310n. As shown in FIG. 1, the side view shows a configuration of a double "E" along an imaginary axis of symmetry radially to the axis "W" through the central pole section 310m. The respective middle pole sections 310 sit on the inside on an abutment 310w which runs concentrically to the axis W of the shaft.

The pole elements 310 are arranged symmetrically about the shaft axis W and are held on the outside by tension rings 310s.

While the clamping ring 310s running around the middle pole sections 310m is smooth on the outside, the clamping rings (shrink rings) 310s' arranged on the free ends of the outer pole fingers 310f are formed with a plurality of grooves running in the direction of the axis W. , which are used to guide cooling air, as will be described below.

Insulating bodies 312 are located in the pole grooves 310n, the basic structure of which is shown in FIGS. 12, 13.

12 shows a partial segment of a groove lining or an insulating body 312, which has an annular, continuous central region 312m, from which sections 312a, 312i extend radially outwards and inwards, which by 90 ° before insertion into the corresponding pole groove 10n be bent up.

In this way, all the inner surfaces between opposite sections of the pole fingers 310f and the associated area of the middle pole section 10m can be covered with a single insulating body 312. To fix the insulating body 312 in the pole grooves 310n, the sections 312a, 3l2i are formed at their free ends with outwardly projecting latching lugs 312r which, as shown in FIG. 13, snap into corresponding slot-like receptacles 310a of the pole fingers 310f.

11 to 13 further shows that in each pole groove 310n (i.e. both the inner and the outer pole groove) two excitation coils 314i, 314a are arranged one above the other and opposite the pole fingers 310f and the middle pole section 310m are insulated by the described insulating body 312 and from one another by insulating spacers 316 which have an annular shape and are likewise latched in the slot-shaped recesses 310a of the pole fingers 310f.

In this way, not only is a particularly simple and reliable isolation of the parts from one another achieved, but at the same time an (undesirable) displacement of the ring-shaped excitation coils 314i, 314a in the direction of the axis W and thus out of the pole grooves 310n is prevented different.

The electrical connection elements for the excitation coils 314i, 314a extend outward between the spaced pole fingers 310f, as indicated in FIG. 11.

13 shows that the excitation coils 314i, 314a only extend over part of the height of the pole grooves 310n. The remaining section of the pole grooves 310n is filled, as shown in FIG. 11, by rotor sheet metal rings 316i, 316a, which are arranged on a carrier disk 318, which here consists of aluminum and is connected via plastic carriers 318k. The rotor plate rings 316i, 316a are each formed on their inner and outer circumferential surfaces with groove-like depressions, in correspondence with the distribution of the pole fingers 310f, so that the rotor plate rings 316i, 316a fit precisely in the area not filled by the excitation coils 314i, 314a of the pole grooves 310n can be used.

However, the rotor can also be formed from other materials without further ado.

The carrier disk 318 is seated on the shaft and is enclosed overall by a housing 320, which is not described in any more detail here.

The middle pole sections 310m and the pole fingers 310f of the pole pieces are cast with a two-component epoxy resin, just like the excitation coil 314i, 314a within the pole grooves 310n.

The groove formation or the insulating body 312 consists, for example, of hard paper.

The pole elements 310 are formed from soft iron sheets, while the excitation coils 314i, 314a are coils wound from copper wire. In the exemplary embodiment, the rotor shaft (not shown) is made of steel, as are the tension rings (shrink rings) 310, 310s.

The machine shown in the figures is designed as a surface-cooled machine. For this purpose, it is necessary to conduct the heat loss generated in the machine to the machine surface and from there to the environment. The heat is transported in the machine through heat conduction and forced convection of the machine air.

The structural arrangement of the potting elements between the stator iron elements, i.e. in particular the pole elements 310 is selected so that heat can be dissipated via the encapsulation element shrink ring 310s-housing 312, but also by forced convection (air circulation). So that a forced, sufficiently turbulent flow can be generated in the machine, fan blades 322 are attached to the rotor disks 318.

The air is then circulated in the direction of arrow L (FIG. 11) as a double flow by both rotor carrier disks 318. On the back of the rotor disk 318, the air releases the absorbed heat to the corresponding end shield of the housing 312. Here, too, cooling fins can again be arranged on the inside of the housing 312.

Claims

EXPECTATIONS

1. Electrical machine, comprising a rotor rotating about an axis and a stator, which comprises a set with a plurality of C-shaped pole elements arranged at equal angular intervals around the axis, each with a base bar and two of this protruding pole finger encompasses a stator winding and generates a magnetic field line course which is oriented approximately parallel to a plane of a plane sheet passing through the axis, characterized in that the pole elements (34) move in an azimuth direction (112) about the axis (14) circumferential recess (82) of a stator carrier (22, 24) are inserted and that the pole elements (34) are fixed in the recess (82) by an adhesive.

2. Electrical machine .nach claim 1, characterized gekenn¬ characterized in that the pole elements (34) in Azimutalrich¬ direction by the base webs (36) of the Polele¬ elements (34) lying base support elements (114) are fixed against each other.

3. Electrical machine according to claim 1 or 2, characterized in that the pole elements (34) are supported against one another by finger support elements (120) arranged between successive pole fingers (38, 40, 42).

4. Electrical machine according to claim 2 or 3, characterized in that each support element (114, 120) comprises a hardened casting compound (118, 124).

5. Electrical machine according to one of claims 2 to 4, characterized in that each support element (114, 120) one in spaces between the Pol¬ elements (34) arranged and of the potting compound (118, 124) in the flowable state interspersed holding body ( 116, 122).

6. Electrical machine according to one of the preceding claims, characterized in that the recess (82) two in the azimuthal direction (112) to the axis

(14) extending and facing side walls (84, 86).

7. Electrical machine according to claim 6, characterized gekenn¬ characterized in that the pole elements (34) between the side walls (84, 86) of the recess (82) sit and of these against a movement transverse to the Azimutalrich¬ direction (112) are fixed.

8. Electrical machine according to claim 6 or 7, characterized in that the recess (82) has a floor (88) extending between the side walls (84, 86).

9. Electrical machine according to claim 8, characterized gekenn¬ characterized in that the pole elements (34) sit with their base web (36) on the bottom (88) of the recess (82).

10. Electrical machine according to one of the preceding claims, characterized in that the Polele¬ elements (34) in the recess (82) with a serving as an adhesive potting compound (118) are fixed.

11. Electrical machine according to claim 10, characterized ge indicates that the pole elements (34) are embedded with their base web (36) into which the recess (82) essentially filling potting compound (118).

12. Electrical machine according to the preamble of claim 1 or according to one of the preceding claims, characterized in that the pole elements (34) are held in alignment by positioning rings (100, 102) at equal angular intervals on the stator carrier (22, 24) .

13. Electrical machine according to claim 12, characterized ge indicates that the positioning rings (100, 102) on the stator carrier (22, 24) can be mounted.

14. Electrical machine according to claim 12 or 13, characterized in that the positioning rings (100, 102) fix each pole element (34) in the azimuthal direction (112) between two projections (104, 106).

15. Electrical machine according to one of claims 12 to 14, characterized in that two spaced positioning rings (100, 102) are seen vor¬.

16. Electrical machine according to claim 15, characterized in that the positioning rings (100, 102) are arranged on opposite sides of the recess (82).

17. Electrical machine according to one of the preceding claims, characterized in that the pole fingers (34) extend approximately parallel to the axis (14).

18. Electrical machine according to claim 17, characterized in that the pole elements (34) are inserted in the direction parallel to the axis (14) in the recess (82).

19. Electrical machine according to claim 17 or 18, da¬ characterized in that the side walls (84, 86) of the recess (82) lie on cylindrical surfaces or conical surfaces to the axis (14).

20. Electrical machine according to one of claims 17 to 19, characterized in that the bottom (88) of the recess (82) lies in a plane extending transversely to the axis (14).

21. Electrical machine according to one of the preceding claims, characterized in that the stator carrier (22, 24) extends in the radial direction to the axis (14).

22. Electrical machine according to claim 21, characterized ge indicates that the stator carrier (22, 24) forms a bearing plate for mounting the rotor.

23. Electrical machine according to claim 22, characterized in that the bearing plates (22, 24) forming the stator carrier are part of a housing (10).

24. Electrical machine according to one of the preceding claims, characterized in that several sets of pole elements (34) are provided.

25. Electrical machine according to claim 24, characterized in that the pole fingers (38, 40, 42) of the pole elements (34) from different sets (30, 32) extend parallel to one another.

26. Electrical machine according to claim 25, characterized in that a set (30, 32) of pole elements (34) is arranged on mutually opposite gate carriers (22, 24) and the pole fingers (38, 40, 42) are directed towards each other.

27. Electrical machine according to one of the preceding claims, characterized in that the Polele¬ elements (34) are E-shaped.

28. Electrical machine according to one of the preceding claims, characterized in that the Polele¬ elements (34) are constructed from laminated cores.

29. Electrical machine according to claim 28, characterized ge indicates that the laminated cores (34) in the azimuthal direction (112) have stacked sheets (180).

30. Electrical machine according to claim 28 or 29, characterized in that each sheet stack (34) has the same number of identical sheets (180).

31. Electrical machine according to one of claims 1 to 27, characterized in that the pole elements (34) are made of iron powder.

32. Electrical machine according to one of claims 1 to 27, characterized in that the pole elements (34) are made of a sintered material.

33. Electrical machine according to the preamble of claim 1 or according to one of the preceding claims, characterized in that the pole elements (34) on the stator carrier (22, 24) are elastically mounted.

34. Electrical machine according to claim 33, characterized in that the pole elements (34) receiving recess (82) is arranged in a retaining ring (190) and that the retaining ring (190) on a stator stand (22 ') is elastic is stored.

35. Electrical machine according to claim 34, characterized in that the retaining ring (190) is mounted on two mutually opposite sides (198, 200) by elastic elements (202, 204) on the stator stand of the stator carrier (22 ¹ ) .

36. Electrical machine according to one of the preceding claims, characterized in that the Polele¬ elements (34) following the stator winding (56, 58) have a free Polnutabschnitt (64, 66), in which magnetic circuit elements (74, 76) of Intervene with the rotor (12).

37. Electrical machine according to one of the preceding claims, characterized in that the magnetic circuit elements (74, 76) ^{'are formed} in the form of laminated cores.

38. Electrical machine according to claim 37, characterized in that the laminated cores (74, 76) in the direction of the axis (14) of the rotor (12) have stacked laminations (184).

39. Electrical machine according to the preamble of claim 1 or according to one of the preceding claims, characterized in that the rotor (12) passes through a plurality of the magnetic field line course (78, 89) of the C-shaped pole elements (34) ¬ baren in the azimuthal direction (112) successively arranged individual magnetic circuit elements (74, 76).

40. Electrical machine according to one of claims 37 to 39, characterized in that a gap with respect to the magnetic conductivity is provided between successive magnetic circuit elements (74, 76).

41. The electrical machine as claimed in claim 40, characterized in that the gap in the azimuthal direction (112) has an extent which is at least half the extent of one of the magnetic circuit elements (74, 76) in the azimuthal direction (112).

42. Electrical machine according to claim 40 or 41, characterized in that intermediate pieces (142, 144) are arranged in the gaps between the magnetic circuit elements (74, 76).

43. Electrical machine according to claim 42, characterized ge indicates that the intermediate pieces (142, 144) are made of a stray field shielding material.

44. Electrical machine according to claim 42 or 43, characterized in that the intermediate pieces (142, 144) bear positively on the magnetic circuit elements (74, 76).

45. Electrical machine according to claim 42 or 44, characterized in that the intermediate pieces (142, 144) positively fix a central region (146) of the magnetic circuit elements (74, 76).

46. Electrical machine according to one of claims 42 to 45, characterized in that the intermediate pieces (142, 144) sit on a rotor body (130, 138, 140) carrying the magnetic circuit elements (74, 76).

47. Electrical machine according to one of the preceding claims, characterized in that the magnetic circuit elements (74, 76) are integrally formed on the rotor body (130, 138, 140).

48. Electrical machine according to one of the preceding claims, characterized in that it has a plurality of motor units (170, 172, 174, 176), each with a set of C-shaped pole elements (34) and a set of magnetic circuit elements (74, 76) associated therewith includes.

49. Electrical machine according to claim 48, characterized in that the pole elements (34) and magnetic circuit elements (74, 76) of different motor units (170, 172, 174, 176) are arranged such that the motor units (170 , 172, 174, 176) form a sequence of motor units (170, 174, 172, 176) operating with a constant phase shift between successive motor units (170, 174, 172, 176).

50. Electrical machine according to claim 49, characterized ge indicates that the magnetic circuit elements (74, 76) of different motor units (170, 172, 174, 176) on the rotor (12) are arranged with an angular offset relative to one another.

51. Electrical machine according to one of the preceding claims, characterized in that the stator winding (56, 58) comprises a ring coil running around the axis (14) and arranged approximately coaxially to the latter.