EP3785357A1

EP3785357A1 - Electrical machine with electric motor and magnetic gear

Info

Publication number: EP3785357A1
Application number: EP19723628.4A
Authority: EP
Inventors: Gerald Jungmayr; Günther Weidenholzer; Edmund MARTH
Original assignee: Ebm Papst Mulfingen GmbH and Co KG
Current assignee: Ebm Papst Mulfingen GmbH and Co KG
Priority date: 2018-04-26
Filing date: 2019-04-26
Publication date: 2021-03-03
Also published as: US20210265905A1; CN112602257A; DE102018110151A1; WO2019204848A1

Abstract

The invention relates to an electrical machine, in particular an electric drive unit comprising an electric motor and a magnetic gear. In accordance with one embodiment the electrical machine has the following: a housing, a first shaft arranged in the housing, by means of which first shaft a first permanent magnet assembly and a second permanent magnet assembly are rigidly connected, and a stator arranged internally on the housing, which stator together with the first shaft forms the electric motor. The electrical machine also has a tubular machine element with a plurality of ferromagnetic pole shoes, into which the first shaft is at least partially inserted, such that the first shaft is situated coaxially with the tubular machine element and the second permanent magnet assembly is situated within the tubular machine element. The first shaft is mounted at a first end on the tubular machine element by means of a first bearing inside the tubular machine element. An annular third permanent magnet assembly is arranged around the tubular machine element so that the second permanent magnet assembly, the tubular machine element and the third permanent magnet assembly form the magnet gear. Either the tubular machine element is mounted rotatably on the housing and the annular third permanent magnet assembly is rigidly connected to the housing, or the tubular machine element is rigidly connected to the housing and the annular third permanent magnet assembly is mounted rotatably on the housing.

Description

ELECTRIC MACHINE WITH ELECTRIC MOTOR AND

MAGNET GEAR

TECHNICAL AREA

[0001] The present description relates to the field of electric drives, in particular an integrated drive unit with an electric motor and a magnetic transmission.

BACKGROUND

[0002] In a magnetic transmission, the two rotors (input and output shafts) are magnetic and not - as in mechanical transmissions - mechanically coupled by means of gears. Compared to mechanical transmissions, therefore, magnetic transmissions have lower friction losses, lubrication can be dispensed with, wear is limited to load-bearing rolling bearings, and noise is lower. In contrast to mechanical gear units, magnetic gear units are not damaged in the event of overload, but fall into slippage. By reducing the load torque, the magnet gear can be coupled in again. Disadvantages can be iron losses and hysteresis losses, which, however, can be kept small by the use of magnetic sheets.

A magnetic transmission may be integrated with an electric motor in a structural drive unit together (see, for example, EP 2 133 982 A2, GB 2 472 020 A). Such drive units can be used as a direct drive and are therefore sometimes referred to as a pseudo-direct drive. The inventors have made it their mission to improve existing concepts for integrated drive units with electric motor and magnetic transmission.

SUMMARY

It is described an electrical machine, in particular an electric drive unit with an electric motor and a magnetic transmission. According to one embodiment, the electric machine comprises: a housing, one in the housing arranged first shaft to which a first permanent magnet assembly and a second permanent magnet assembly are rigidly connected, and a stator disposed inside the housing, which forms the electric motor together with the first shaft. The electric machine further comprises a tubular machine element having a plurality of ferromagnetic pole shoes into which the first shaft is at least partially inserted such that the first shaft is coaxial with the tubular machine element and the second permanent magnet arrangement is within the tubular machine element. The first shaft is mounted at a first end by means of a first bearing in the interior of the tubular Maschi nenelements at this. An annular third permanent magnet arrangement is arranged around the tubular machine element such that the second permanent magnet arrangement, the tubular machine element and the third permanent magnet arrangement form the magnetic transmission. In this case, either the tubular machine element is rotatably mounted on the housing and the annular third permanent magnet arrangement rigidly connected to the housing, or the tubular machine element is rigidly connected to the housing and the annular third permanent magnet arrangement is rotatably mounted on the housing.

[0005] According to a further embodiment, the electric machine has the following: a first shaft arranged in the housing, to which a first permanent magnet arrangement and a second permanent magnet arrangement are rigidly connected, a stator arranged inside the housing, which together with the stator first shaft forms the electric motor, and a tubular machine element having a third permanent magnet arrangement, in which the first shaft is at least partially inserted so that the first shaft is coaxial with the tubular machine element and the second permanent magnet arrangement within the tubular machine element , The first shaft is mounted at a first end thereof by means of the first bearing inside the tubular machine element. An annular arrangement with a plurality of pole shoes is arranged around the tubular machine element so that the second permanent magnet arrangement, the tubular machine element with the third permanent magnet arrangement and the annular arrangement with a plurality of pole shoes form the magnetic transmission. In this case, either the tubular machine element is rotatably mounted on the housing and the annular arrangement with a plurality of pole shoes is rigidly connected to the housing, or the tubular machine element is rigidly connected to the housing and the annular array with a plurality of pole pieces rotatably supported on the housing.

According to a further exemplary embodiment, the electric machine has the following: a housing, a first shaft arranged in the housing and designed as a hollow shaft, in the interior of which at least one first permanent magnet arrangement and at least one second permanent magnet arrangement are arranged, one inside the housing arranged stator which forms the electric motor together with the first shaft, and a tubular machine element with a plurality ferromagnetic Polschuhen, in which the first shaft is at least partially inserted so that the first shaft coaxial with the tubular machine element and the at least second permanent magnet arrangement in within lie of the tubular machine element. An annular third permanent magnet arrangement is arranged around the tubular machine element so that the two te permanent magnet assembly, the tubular machine element and the third Perma nentmagnetanordnung form the magnetic transmission. In this case, either the tubular Ma machine element is rotatably mounted on the housing and the annular third permanent magnet assembly rigidly connected to the housing, or the tubular Maschinenele element is rigidly connected to the housing and the annular third Permanentmagnetan Regulation is rotatably mounted on the housing.

BRIEF DESCRIPTION OF THE DRAWINGS

Embodiments are tert erläu detail below with reference to figures. The illustrations are not necessarily to scale and the Ausführungsbei games are not limited to the aspects presented. Rather, value is placed to represent the underlying principles of the embodiments. In the pictures shows:

Figure 1 is a sectional view illustrating a longitudinal section of an ers th embodiment of a drive unit with electric motor and magnetic gear.

Figure 2 shows a first modification of the embodiment of Fig. 1, wherein the arrangement of the permanent magnets has been modified. Figure 3 shows a second modification of the embodiment of FIG. 1, wherein a solid shaft is used as the rotor of the electric motor instead of a hollow shaft.

Figure 4 shows a third modification of the embodiment of Fig. 1, wherein the rotor has different outer diameter.

Figure 5 shows a fourth modification of the embodiment of Fig. 1, wherein the housing has two relatively rotatable housing parts

FIG. 6 illustrates a modification of the example from FIG. 5, in which the modulator is rigidly connected to the housing of the electric motor and a further housing part functions as an external rotor.

Figure 7 illustrates a fifth modification of the example of Fig. 1, wherein the engine was designed as a bearingless engine.

Figures 8 and 9 illustrate two further modifications of the embodiment of FIG. 1, wherein the inner hollow shaft 11 is cantilevered.

Figures 10 and 11 illustrate two modifications of the embodiment of FIG. 6, wherein the inner hollow shaft 11 is cantilevered.

FIG. 12 illustrates a further modification of the exemplary embodiment from FIG.

1, wherein the modulator of the magnetic transmission is cantilevered.

Figure 13 illustrates a further modification of the embodiment of FIG. 1 with a forced ventilation of the housing interior.

Figure 14 illustrates a further modification of the embodiment of Fig. 1, in which a magnetic field sensor is provided on the board arranged in the housing.

DETAILED DESCRIPTION

The embodiments described here relate to a new concept for the integration of electric motor and magnetic transmission (magnetic transmission, magnetic gear) in a housing, whereby a compact electric drive unit (electric drive unit) is formed with high power density. Such drive units are also referred to as Magnetic Gear Motor (MGM). A high power density is thereby achieved that the electric motor with comparatively high speed (eg up to 30,000 revolutions per minute or more) is operated. The magnetic transmission reduces the high speed to a "normal" value, for example in the range of 1000 to 6000 revolutions per minute, whereby the available torque is translated accordingly. It is understood that the embodiments described herein with electric motor can also be operated as a generator (if the electric motor for the generator operation is suitable). Structurally, there is no significant difference between electric motor and generator.

In a majority of the known drive units with Magnetge gear and electric motor (MGM units) magnetic gear and electric motor are arranged coaxially in a plane. That is, motor and magnetic gear are not axially offset side by side, but are interleaved to the same axis of rotation rotatably arranged. This arrangement is for example referred to as PDD {pseudo direct drive). Such MGM units therefore have comparatively large diameter-length ratios. The embodiments shown here are based on a side-by-side arrangement of the engine and transmission with a relatively small diameter compared to the length.

Compared to MGM arrangements in which the motor and magnetic gear are arranged coaxially inside one another with the stator of the motor, the side-by-side arrangement has the advantage that the inner rotor can have a smaller diameter , As a result, smaller bearings are possible, which usually also the bearing losses are lower. Compared to MGM arrangements in which the motor and magnetic gear are disposed coaxially inside each other with the stator of the motor, the side-by-side arrangement has the advantage that the effective air gap between the permanent magnet assembly of the high-speed rotor and the stator can be smaller.

Fig. 1 is a sectional view illustrating a longitudinal section (along the axis of rotation As) by an embodiment of an electric drive unit. As already explained, it is a structural unit in which an electric motor 40 and a Mag netgetriebe 30 are arranged in a housing 50. According to the example shown the stator 41 of the electric motor is rigidly connected to the housing 50. In one embodiment, the stator 41 is implemented with a three-phase winding system. However, other phase numbers, for example between one and six, are possible. The arrangement of the coils can be concentrated or distributed. Another possibility is the use of toroidal coils (toroidal motor). If the stator winding is correctly energized, a magnetic rotating field with a pole pair number PMOT is formed in the air gap of the motor (PMOT> 1). To guide the magnetic flux, the stator may have a laminated core (stack of laminated metal sheets) or a component made of soft magnetic composite (SMC). A version without laminated core (air-core motor) is possible. In both cases, a magnetic flux is formed in the radial direction during operation.

The rotor of the electric motor is formed by a permanent magnet arrangement 12 with one or more permanent magnets 12. In the example shown, the permanent magnet arrangement 12 is arranged in the interior of the hollow shaft 11. In particular, at high speeds, the hollow shaft 11 can serve as centrifugal force protection for the Permanentmagnetan Regulation 12. At one end, the hollow shaft 11 is mounted on the housing 50 via a rolling bearing 14 (e.g., ball bearings). On the second bearing point of the hollow shaft 11 will be discussed later. The hollow shaft does not require a shaft shoulder and can therefore be easily manufactured. Depending on the implementation, the hollow shaft 11 may also have several paragraphs with different diameters. The hollow shaft 11 has a comparatively high bending stiffness at a comparatively small moment of inertia, whereby the hollow shaft 11 can be constructed so that resonances of bending vibrations are outside the speed range of the high-speed rotor.

The electric motor can be designed, for example, as a brushless synchronous motor (BLDC motor, brushless DC moto). Alternatively, other types of motors may be used, such as e.g. Asynchronous motors, reluctance motors, etc., which generate a radially directed, magnetic flux and often do not require a permanent magnet assembly 12 in the rotor. The operation of a BLDC motor (as well as other Motorty pen) is known per se and will therefore not be explained further here.

In general, a magnetic gear has an inner, rapidly rotating rotor (in Fig. 1, this rotor Rl with a small number of pole pairs pi), a modulator (in Fig. 1 is this rotor R2 with p ₃ + pi or p ₃ -pi pole shoes) and an outer, slowly rotating rotor (in FIG. 1, this is rotor R3 with pole pair number p ₃ ). In many magnetic transmission designs, the modulator is stationary and the outer rotor R3 represents the output of the transmission. Alternatively, as in the example shown in FIG. 1, the outer rotor R3 may be rigidly connected to the housing 50 and therefore quiet stand. In this case, the modulator (rotor R2) is the output of the transmission. To remain consistent in the description, the three main components of the magnet gear are all referred to as rotors (rotor Rl, rotor R2 and rotor R3), although depending on the design rotor R2 or rotor R3 may be rigidly connected to the housing.

The pi pole pairs of the rotor Rl are formed by a second Permanentmagnetan Regulation 13 with at least one permanent magent, which are also arranged in the interior of the hollow shaft 11 in the case of the game shown. The p ₃ pole pairs of the rotor R3 are formed by a third annular permanent magnet arrangement 32, which comprises a plurality of permanent magnets and which encloses the modulator R2. The p ₃ + pi (or alternatively p ₃ -pi) Pohl shoes of the modulator R2 are formed of ferromagnetic material. When p ₃ + pi pole shoes of the modulator 21 (rotor R2) is the Untersetzungsver ratio of the transmission (from the shaft 11 to the output shaft 23) equal to p ₃ / pi + l. The shaft 11 and the output shaft 23 have the same direction of rotation in this case. For p ₃ -pi pole shoes of the modulator 21, the reduction ratio of the transmission (from the shaft 11 to the output shaft 23) is equal to (p ₃ / pi-1). The shaft 11 and the output shaft 23 wei sen in this case, an opposite direction of rotation. In addition, the amount of the reduction ratio also changes. In some embodiments, the first permanent magnet assembly 12 and the second permanent magnet assembly 13 may be stirred or formed as a unit. In the latter case, the first Permanentmag netanordnung 12 would be a portion of a permanent magnet unit arranged along the longitudinal axis and the second permanent magnet assembly 13, a second portion which lies in the axial direction adjacent to the first section.

As shown in Fig. 1, the hollow shaft 11 of the electric motor 40 is also part of the inner, rapidly rotating rotor Rl of the magnetic gear 30. In the region of the magnetic gear 30 is therefore in the hollow shaft 11, the second permanent magnet assembly 13, the together forms with the hollow shaft 11, the inner high-speed rotor Rl (ie the input) of the magnetic transmission 30. In one embodiment, the pole pair number pi is one (the NS polarization is indicated by arrows), which is at Given output speed at the output of the transmission, a high reduction and thus a high speed (and thus high performance) of the electric motor 40 allows. Alternatively, the pole pair number pi may also be two.

The modulator (rotor R2) of the magnetic transmission is formed by a rohrför Miges machine element, e.g. a further hollow shaft 22 and the pole pieces 21 up, which are arranged along the circumference of the hollow shaft 22. The annular machine element further comprises a shaft 23 (input or output shaft) with a Wellenab set 23 a, which is rigidly connected at one end of the hollow shaft 22 with this. The hollow shaft 22 is therefore closed at one end by the shaft 23 and open at the other end. Pole shoes 21 and hollow shaft 22 may be manufactured as one component. Alterna tive or in addition, the hollow shaft 22 and the shaft 23 may be made in one piece. The hollow shaft 22 is mounted at both ends by means of rolling bearings 24 and 25 on the housing 50. Depending on the construction can be arranged between the bearings 24 and 25 jacks 51 and 52, in which the bearings 24 and 25 are arranged.

A particularly compact construction is obtained when the hollow shaft 11 (rotor R1) is mounted in the interior of the hollow shaft 22 on a shaft portion of the shaft 23 (for example via roller bearings 15). That is, the hollow shaft 11 extends partially inside the hollow shaft 22 and is mounted at the closed end of the hollow shaft 22 at a shaft portion of the shaft 23. When p3 + pi pole shoes of the modulator 21 "does not see the bearing 15, the full speed of the electric motor, but only the difference in rotational speeds at the input and the output of the magnetic transmission 30th

[0031] the outer rotor R3 of the magnetic gear 30 rigid housing with the Ge As mentioned 50 is connected, and thus, strictly speaking, not a rotor, but the stator 31 of the magnet gear 30 to which the permanent magnets may be arranged 32 along the circumference (number of pole pairs p ₃ ). However, it is referred to in terms of a consistent description as the rotor R3, as this component can rotate in some embodiments also ren (for example, the modulator 21 is fixed, see, for example, Fig. 6). Similar to the stator 41 of the electric motor, the stator 31 for guiding the magnetic flux packet (or a component of SMC) have a sheet metal to achieve a high magnetic flux density in the air gap. The housing 50 may be made in one piece or in several parts. Depending on the type of motor, a control electronics (motor electronics) may be necessary, which may be arranged on a printed circuit board (PCB) 61, which in turn may be mounted inside the housing. In the example shown, the hollow shaft 11 is a piece passed through the circuit board 61, so that angle sensors can be arranged directly on the circuit board 61 (see also Fig. 14).

The high-speed rotor Rl (hollow shaft 11) is at the same time the rotor of the electric motor and the drive rotor (in engine operation) of the magnet gear; Due to the arrangement of the bearings 14 and 15, it does not have to be connected to the outside and can therefore be arranged completely inside the housing 50. The stator 41 of the electric motor 40, the stator 31 (rotor R3) of the magnetic transmission 30 and housing 50 together form a compact assembly. The bearings, particularly the high-speed bearing 14 and the fast-rotating bearing 15, may be formed as ceramic bearings or as hybrid bearings in which bearing rings and rolling elements are made of different materials (e.g., steel bearing rings and ceramic balls). Ceramic or hybrid bearings also represent a higher magnetic resistance for the magnetic field lines of the permanent magnet arrangements than conventional bearings made of steel. In particular, a magnetic "short circuit" of the magnetic field lines through the bearings can be reduced. Compared to conventional bearings made of steel, the eddy current losses in the bearing are completely avoided in ceramic bearings. When using hybrid bearings, the eddy current losses due to the stray magnetic field of the permanent magnet arrangement 12 or 13 are reduced.

Fig. 2 shows an alternative to the example of Fig. 1. The embodiment of Fig. 2 is almost identical to the previous example with the only difference that the permanent magnets 32 '(numeral 32 in Fig. 1) instead of Stator 31 (rotor R3) are arranged on the rotor R2 (that are part of the above-mentioned tubular machine element). Whereas in FIG. 1 the modulation of the permanent magnetic field by the pole shoes takes place on the rotor R2 (modulator), this is done in FIG. 2 by the external rotor R3 (in FIG. 1 and FIG. 2, the rotor R3 is thus stationary taken as a stator acts). The stator 31 (rotor R3) has for this purpose an annular arrangement with a plurality of pole shoes 21 '. In the example of Fig. 2, the stator 31 performs the function of the modulator, whereas the magnetic field is generated by the permanent magnet assembly 21 'of the rotor R2 (tubular machine element). Incidentally, the structure, in particular the bearing of the hollow shaft 11 at a shaft portion of the shaft 23 in the interior of the hollow shaft 22 is the same as in the previous example of FIG. 1st

Fig. 3 shows a further alternative to the example of Fig. 1. The Ausfüh tion of Fig. 3 is almost identical to the previous example with the single-gen difference that instead of the hollow shaft 11, a solid shaft 1 V is provided. The permanent magnets 13 and 14 are therefore not inside, but outside of the shaft 1 V arranged. Nonetheless, similar to Fig. 1, the shaft 1 V is mounted internally on the hollow shaft 22 or in a central bore of the shaft 23. Incidentally, the construction is the same as in the previous example of FIG. 1. The embodiment according to FIG. 3 may be suitable, for example, for applications in which no centrifugal force protection is required due to smaller rotational speeds or smaller outer diameters of the magnet arrangements 12 and 13.

Fig. 4 shows a variant of the example of Fig. 1, in which the hollow shaft 11 has two sections with different diameters. Thus, for the electric motor 40 and the magnetic gear 30, different diameters in the region of the air gap (i.e., between the outer diameter of the hollow shaft 11 and the inner diameter of the modulator 21 in the magnetic gear and between the outer diameter of the hollow shaft 11 and the stator 41 in the engine) can be realized.

Fig. 5 shows a variant of the example of Fig. 1, in which the rotor R3 is mounted relative to the housing 50 (see Fig. 5, bearings 26a and 26b). The now rotatably mounted rotor R3 (in Fig. 1 rigidly coupled to the housing 50) can be driven and / or act as an output. If the rotor R3 were held in place, the function of the embodiment according to FIG. 5 would be the same as in FIG. 1. The bushings 51 and 52 (see FIG. 1) are not used in this case. Instead, the sleeve 50b, which is rotatably mounted on the housing 50 by means of the bearings 26a and 26b, functions as an external rotor. The hollow shaft 22 is mounted with the bearings 24 and 25 on the sleeve 50b (instead of as in Fig. 1 on the housing 50). As he suggests, in the illustrated example, the outer rotor R3 of the magnet gear 30 is not rigidly coupled to the stator 41 of the electric motor 40 and the drive unit has there with two outputs. The first output forms the shaft 23 as in the example of Fig. 1 and the second output forms the sleeve 50b, which can rotate as mentioned and forms the external rotor. One of the power take-offs or both power take-offs can also be used as a drive, wherein the mechanical power at the two Ab tri eben / drives be combined. Depending on whether the net power is positive or negative, the motor 40 is operating in motor or generator mode.

Fig. 6 illustrates a modification of the example of Fig. 5, in which the modulator 21 is rigidly connected to the housing of the electric motor 40 (housing part 50a). In this example, the bearings 26a and 26b are omitted and the magnets 32 (rotor R3) are rigidly connected to a housing part 50b which functions as an external rotor. Instead of the (rotatable) hollow shaft 22, a (non-rotatable) sleeve 22 'is provided. In the illustrated example, the sleeve 22 'has a shoulder 22a which is fixedly connected to the housing part 50a. For example, the sleeve 22 '(with the shoulder 22a) is screwed or pressed into the housing part 50a. The output shaft 23 is replaced by a housing cover 50c. The output forms the housing part 50b, which is an external rotor similar to the example of FIG. The motor 40 is the same in this example as in the previous examples; the difference to the example of Fig. 5 is only there that the rotor R2 (with modulator 21) is "held" by the rigid coupling with the housing part 50a. The hollow shaft 11 is - similar to the previous example - with means of the roller bearing 15 inside of the housing cover 50 c stored (in this example, the storage obviously the role of the shaft 23 takes over). The rolling bearings 14 and 15 Kgs nen as in the example of FIG. 5 be constructed practically the same (depending on the application as a steel bearing, ceramic bearings or hybrid bearings). Incidentally, the present example corresponds essentially to the example from FIG. 5. In the case of p3 + pi pole shoes of the modulator 21, the reduction ratio of the transmission (from the shaft 11 to the output 50b) is equal to -p ₃ / pi. The shaft 11 and the output 50b have opposite directions of rotation. For p ₃ -pi pole shoes of the modulator 21, the reduction ratio of the transmission (from the shaft 11 to the output 50b) is equal to p ₃ / pi. The shaft 11 and the output 50b have the same direction of rotation here.

The example of FIG. 6 can be further modified by using a solid shaft instead of the hollow shaft 11 as in the example of FIG. 3. According to a further modification, the permanent magnets 32 are arranged on the rotor R2 (sleeve 22 ') instead on the outer rotor R3 (similar to the example of Fig. 2), which as mentioned with reference to the example of Fig. 2 leads to the fact that the outer rotor R3 takes over the function of Modula sector. The embodiment of Figure 7 is a further modification of the example of Figure 1, wherein the motor 40 is designed as a bearingless motor. The bearing 14 can therefore be omitted. Incidentally, reference is made to the description of FIG. 1. As shown in FIG. 7, the hollow shaft 11 is supported only at one point by means of the roller bearing 15. The bearingless motor generates, in addition to the drive torque and the radial forces that are necessary to keep the hollow shaft 11 in position. For this purpose, the motor 40 can have position sensors which are arranged so that they measure a radial deflection of the hollow shaft 11 in the region of the electric motor 40. Incidentally, reference is made to the comments on Fig. 1. The modifications and variants described with reference to FIG. 1 can also be applied to the example from FIG. 7. In another variant, the hollow shaft is completely magnetically supported (active or passive). In this case, the rolling bearing 15 can be omitted.

The embodiment of Fig. 8 is a further modification of the example of Fig. 1, wherein the bearing 14 is not arranged at the left end of the hollow shaft 11, son countries between the electric motor 40 and the magnetic gear 30. In this example, that between the electric motor 40 and magnetic gear 30 lying bearing of the hollow shaft 11 denoted by l4 '. In contrast to the bearing 14 of FIG. 1, the bearing l4 'of FIG. 8 has a larger diameter, resulting in greater friction losses in the bearing. Incidentally, reference is made to the comments on Fig. 1. The modifications and variants described with reference to FIG. 1 can also be applied to the example of FIG. 8.

The exemplary embodiment from FIG. 9 is a further modification of the example from FIG. 1, wherein the bearing 15 located in the hollow shaft 22 is not arranged at the right end of the hollow shaft 11, but between the electric motor 40 and the magnet gear 30 In this example, the bearing of the hollow shaft 11 lying between the electric motor 40 and the magnetic transmission 30 is designated by 15 '. In contrast to the bearing 15 from FIG. 1, the bearing 15 'of FIG. 9 has a larger diameter, which results in greater friction losses in the bearing. Incidentally, reference is made to the comments on FIG. 1. The modifications described in relation to FIG. 1 can also be applied to the example of FIG. 9. With respect to the two examples of Fig. 8 and 9, it should be noted that a cantilevered mounting of the hollow shaft 11 (projection on the motor side in Fig. 8 and projection on the side of the magnetic transmission in Fig. 9), the resonance frequency of the bending vibration lower is as in the example of Fig. 1. Depending on the rotary speed of the high-speed rotor Rl (hollow shaft 11), this resonance can cause problematic, unwanted vibrations. Furthermore, the bearings l4 'and 15' located axially between the motor 40 and the magnetic transmission 30 can result in a larger (axial) size of the device.

The embodiment of FIG. 10 is a modification of the example of FIG.

6, wherein the bearing 14 is not arranged at the left end of the hollow shaft 11, but between the electric motor 40 and the magnetic gear 30. In this example, the bearing of the hollow shaft 11 lying between the electric motor 40 and the magnetic gear 30 is denoted by l4 ' , In contrast to the bearing 14 from FIG. 6, the bearing l4 'from FIG. 10 has a larger diameter, which results in greater friction losses in the bearing. Incidentally, reference is made to the comments on Fig. 6. As in the example of FIG. 6, the sleeve 22 'replaces the hollow shaft 22 (rotor R2, modulator / pole shoes 21). The sleeve 22 'may have a plurality of heels of different diameters. In the illustrated example, the bearing l4 'on the shoulder 22b inside and the bearing 24 on the shoulder 22b arranged outside, so that the bearing forces of both bearings are substantially in a radial line.

The embodiment of FIG. 11 is a further modification of the example of FIG. 6, wherein the bearing 15 is not disposed at the right end of the hollow shaft 11, but between the electric motor 40 and the magnetic gear 30. In this example, this is between Electric motor 40 and magnetic gear 30 lying bearing of the hollow shaft 11 denoted by l5 '. In contrast to the bearing 15 of FIG. 6, the bearing l5 'of FIG.

11 a larger diameter, which has greater friction losses in the camp result. Incidentally, reference is made to the comments on Fig. 6. As in the example of FIG.

6 replaced the sleeve 22 ', the hollow shaft 22. The sleeve 22' may have several paragraphs with ver different diameters. In the example shown, the bearing 15 'on the shoulder 22b is arranged on the outside and the bearing 24 on the shoulder 22b on the outside, so that the bearing forces of both bearings lie substantially in a radial line. Even in the examples shown in FIGS. 10 and 11, due to the cantilevered mounting of the hollow shaft 11, resonances of bending oscillations can be problematic (depending on the engine speed).

The embodiment of FIG. 12 is a further modification of the example of FIG. 1, wherein the bearing 24 is arranged not to the left of the modulator 21, but to the right thereof. The bearings 24 and 25 are thus on the same side of the modulator 21. Incidentally, reference is made to the description of FIG. 1. With reference to FIG. described modifications and variants can also be turned to the example of FIG. 12 at. The present example can be used in particular with a comparatively short axial length of the magnetic transmission 30.

Based on the examples described herein, further examples may be made by combining features from the various examples. For example, depending on the application, plain bearings may also be used in all embodiments instead of roller bearings. In all embodiments, the inner hollow shaft 11 can be replaced by a solid shaft 1 V (cf., exemplary embodiment of FIG. By two or more shaft sections with different

Diameter of the inner hollow shaft 11, the size and the position of the magnetically active seed air gaps can be influenced. The inner bearing 14 of the hollow shaft (see Fig. 1) can be replaced by an external bearing. Many other such modifications are possible without changing the function of the embodiments described herein.

The embodiment of FIG. 13 is a further modification of the example of FIG. 1 with a forced ventilation of the interior of the housing 50. On the hollow shaft 11, a fan 16 is arranged, which ensures convection in the interior of the housing. Air is drawn into the interior of the housing at one (axial) end of the housing 50 (for example at the front end) via one or more inlets 55. The air flows through the Elekt romotor and the magnetic gear and can dissipate heat. At the other, the inlets 55 opposite end of the air passes through one or more outlets 56 back to the outside. In the example shown, the outlets 56 extend through the waves paragraph 23a of the output shaft 23. The air flow is indicated in Fig. 13 with "L". On the other hand, the example shown in FIG. 13 is identical to that of FIG. 1 and reference is made to the above explanations. The components responsible for ventilation can also be used in other embodiments.

Embodiment of Fig. 14 is a further modification of the example of Fig. 1. In this embodiment, the electric motor is a BLDC motor, for example. To control the electronic commutation of the stator winding, a measurement of the angular position of the rotor is necessary. For this purpose, a magnetic field sensor 62 is arranged on the circuit board 61 to save space, for example a Hall sensor or a magneto-resistive (MR) sensor. Since the printed circuit board 61 is inserted into the housing in a space-saving manner at right angles to the axis of rotation. is built, the sensor 62 may be attached directly to the circuit board 61 and at the same time be arranged in the vicinity of the stator winding 42. Incidentally, the example illustrated in FIG. 13 is identical to that of FIG. 1, and reference is made to the above explanations. The arrangement of the sensor 62 on the circuit board 61 can play in all Ausführungsbei- play, where an angle measurement is necessary, are used. For certain appli cations it may be necessary (in addition to or as an alternative to the sensor 62) to use a rotary angle sensor during the output (rotor R2 and / or rotor R3) to allow precise control of the angle position on the output.

Claims

1. An electric machine comprising:

a housing (50);

a first shaft (11) arranged in the housing, with which a first permanent magnet arrangement (12) and a second permanent magnet arrangement (13) are rigidly connected;

a stator (41) arranged inside the housing (50) and forming together with the first shaft (11) an electric motor (40);

a tubular machine element (R2, 22, 22 ') with a plurality of ferromagnetic pole shoes (21) into which the first shaft (11) is at least partially inserted so that the first shaft (11) is coaxial with the tubular machine element (R2, 22 , 22 ') and the second permanent magnet arrangement (13) lie within the tubular machine element (R2);

a first bearing (15), wherein the first shaft (11) at a first end by means of the first bearing (15) in the interior of the tubular machine element (R2, 22, 22 ') is mounted thereon;

an annular third permanent magnet assembly (32) which is arranged around the tubular machine element (R2, 22, 22 '), so that the second Permanentmag netanordnung (13), the tubular machine element (R2, 22, 22') and the third Perma nentmagnetanordnung (32) form a magnetic gear (30);

wherein either the tubular machine element (R2, 22, 22 ') is rotatably mounted on the housing (50) and the annular third permanent magnet arrangement (32) is rigidly connected to the housing (50), or the tubular machine element (R2, 22, 22'). ) rigidly connected to the housing (50) and the annular third Permanentmag netanordnung (32) on the housing (50) is rotatably mounted.

2. An electric machine comprising:

a housing (50);

a housing arranged in the first shaft (11), with a first Perma nentmagnetanordnung (12) and a second permanent magnet assembly (13) are rigidly connected ver;

a stator (41) arranged inside the housing (50) and forming together with the first shaft (11) an electric motor (40); a tubular machine element (R2, 22, 22 ') having a third permanent magnet arrangement (31') into which the first shaft (11) is at least partially guided such that the first shaft (11) is coaxial with the tubular machine element (R2, 22, 22 ') and the second permanent magnet assembly (13) lie within the tubular machine element (R2);

an annular arrangement with a plurality of pole pieces (21 ') which is arranged around the tubular machine element (R2, 22, 22'), so that the second Perma nentmagnetanordnung (13), the tubular machine element (R2, 22, 22 ') with the drit th permanent magnet assembly (32) and the annular arrangement with multiple pole shoes (21 ') form a magnetic transmission (30);

wherein either the tubular machine element (R2, 22, 22 ') rotatably supported on the housing (50) and the annular arrangement with a plurality of pole shoes (21') is rigidly connected to the housing (50), or the tubular machine element (R2, 22 , 22 ') is rigidly connected to the housing (50) and the annular arrangement with a plurality of pole pieces (21') is rotatably mounted on the housing (50).

3. The electric machine according to claim 1 or 2, further comprising:

a second bearing (14) supporting the first shaft (11) at a second end on the housing (50), or

a second bearing (l4 ') supporting the first shaft (11) on the housing (50) and disposed between the electric motor (40) and the magnetic gear (30), or

a second bearing (l4 ') supporting the first shaft (11) on the tubular machine element (R2, 22, 22').

4. The electric machine according to one of claims 1 to 3,

wherein the tubular machine element (R2) has a hollow shaft (22) which by means of a third bearing (24) and a fourth bearing (25) rotatably mounted on the housing (50) and the third permanent magnet assembly (32) inside the housing (50 ) is fixed, and

wherein the tubular machine element (R2) further comprises an output shaft (23) rigidly connected to one end of the hollow shaft (22).

5. The electric machine according to one of claims 1 to 3,

wherein the tubular machine element (R2) has a sleeve (22 ') which is non-rotatably connected to the housing (50), and

wherein the third permanent magnet arrangement (32) is fixed to a rotatable housing part (50b) designed as an external rotor.

6. The electric machine according to one of claims 1 to 3,

wherein the tubular machine element (R2) has a hollow shaft (22) which is rotatably mounted by means of at least one third bearing (24, 25),

wherein the third permanent magnet arrangement (32) is fixed to an external rotor (50b) mounted rotatably on the hollow shaft (22), and

wherein the tubular machine element (R2) has a second input or output shaft (23) which is rigidly connected to one end of the hollow shaft (22).

7. The electric machine according to one of claims 1 to 6,

wherein the first shaft (11) is a hollow shaft and the first permanent magnet arrangement (12) and the second permanent magnet arrangement (13) are arranged inside the first shaft (11).

8. An electric machine comprising:

a housing (50);

a first shaft (11), which is arranged in the housing and designed as a hollow shaft, in the interior of which at least one first permanent magnet arrangement (12) and at least one second permanent magnet arrangement (13) are arranged;

a tubular machine element (R2, 22, 22 ') having a plurality of ferromagnetic pole shoes (21) into which the first shaft (11) is at least partially inserted such that the first shaft (11) is coaxial with the tubular machine element (R2, 22) , 22 ') and the at least second permanent magnet arrangement (13) lie within the tubular machine element (R2, 22, 22'); an annular third permanent magnet arrangement (32) which is arranged around the tubular machine element (R2, 22, 22 '), so that the second permanent magnet arrangement (13), the tubular machine element (R2, 22, 22') and the third Per Manentmagnetanordnung (32) form a magnetic gear (30);

9. The electric machine according to one of claims 1 to 8,

wherein the first permanent magnet arrangement (12) and the second permanent magnet arrangement (13) are formed by a first or second section of a permanent magnet unit.

10. The electrical machine according to one of claims 1 to 9,

wherein the electric motor (40) is operable as a generator.