Patent Application
20250030282
The present disclosure relates to a stator arrangement for a radial flux motor. In particular, the disclosure relates to a radial flux motor for a fan, in particular a high-voltage fan, having a stator arrangement of this kind, and to a high-voltage fan having a corresponding radial flux motor. Furthermore, a cooling system having a corresponding high-voltage fan is disclosed. In addition, the present disclosure relates to a method for producing a stator arrangement for a radial flux motor.
Electric machines have long been used for the production of kinetic energy in many technical fields. An electric machine (also called an electric motor or E-motor) is an electric device that can convert electrical energy into mechanical energy. The mechanical energy can in turn be used to generate kinetic energy, with which other devices can be driven. Here, the electric motor generally comprises a stator and a rotor, which are accommodated in a motor housing. The stator is fixed in its position. The rotor moves relative to the stator and is usually situated on a drive shaft that rotates together with the rotor. The rotational energy can be transmitted to other devices via the shaft. Most electric motors generate energy with a magnetic field and a winding current.
In principle, it is possible to draw a distinction between radial flux machines and axial flux machines:
In axial flux machines, the rotor generally consists of a disc-shaped rotor body with two circular surfaces, wherein, normally, at least two permanent magnets are attached to at least one of the latter. The stator is generally of disc-shaped configuration and is arranged in a fixed manner at an axial distance from the rotor. On its side facing the rotor, the stator carries a plurality of circumferentially distributed winding elements. Each winding element in each case comprises a stator tooth, which extends in the axial direction from a stator yoke toward the rotor. The stator tooth is wound with a wire consisting of a metallic, highly conductive material in order to form the winding. When current is applied to the windings, the rotor, which is fastened to the output shaft of the motor, is subjected to a torque resulting from the magnetic field, wherein the generated magnetic flux in an axial flux machine is an axial flux. In axial flux machines, the rotor and the stator are spaced apart in the axial direction by an axial gap and are therefore also frequently referred to as axial gap machines.
In radial flux machines, the rotor generally consists of a cylindrical body, the entire circumference of which carries magnets. The stator is generally of hollow-cylindrical design and surrounds the rotor at a radial distance. Radial flux machines of this kind are also referred to as radial flux machines having an internal rotor (or radial flux machines having an external stator). Alternatively, radial flux machines can also be formed with an external rotor. That is to say that the stator is internal and is surrounded by a hollow-cylindrical rotor. On its inner side (with an internal rotor) or outer side (with an external rotor), the stator carries a plurality of circumferentially distributed winding elements. Each winding element in each case comprises a stator tooth, which extends in the radial direction from a stator yoke toward the rotor. The stator tooth is wound with a wire consisting of a metallic, highly conductive material in order to form the winding. When current is applied to the windings, the rotor, which is fastened to the output shaft of the motor, is subjected to a torque resulting from the magnetic field, wherein the generated magnetic flux in a radial flux machine is a radial flux.
The continuous further development of electric motors and the trend toward the use of electric current as an energy carrier and source is leading to a continuous expansion of the application portfolio of electric motors. Electric motors are used not only in small electronic devices such as notebooks or household appliances, which are usually operated in the low-voltage range. Increasingly, electric motors in larger dimensions are also being used in the high-voltage range at operating voltages of up to 800 volts or 850 volts and more.
Electric motors, especially in high-voltage applications, generally generate heat during operation. In addition, a positionally precise fixing of the stator relative to the rotor is important. In particular, forces acting during operation, for example magnetic forces between the rotor and stator or heat-induced temperature expansions, for example in the stator, constitute further challenges.
It is the object of the present invention to provide a stator arrangement for a radial flux motor with reliable fastening of the stator.
The present disclosure relates to a stator arrangement for a radial flux motor. In particular, the disclosure relates to a radial flux motor for a fan, and to a high-voltage fan having a corresponding radial flux motor. Moreover, the present disclosure relates to a cooling system having a corresponding high-voltage fan and to a method for producing a stator arrangement for a radial flux motor.
The stator arrangement according to the invention for a radial flux motor having an axis of rotation comprises a stator housing, a stator and an encapsulation body. The stator housing defines a circumferential portion for receiving the stator. The stator is arranged on the circumferential portion and is encapsulated in the stator housing. The encapsulation body is form-fittingly connected to the stator housing in such a manner that the stator is fixed at least in the axial direction in the stator housing by the encapsulation body. In particular, the encapsulation body is form-fittingly connected to the stator housing in such a manner that the stator is fixed in a form-fitting and/or friction-locking manner at least in the axial direction in the stator housing by the encapsulation body. In particular, the stator is at least partially embedded radially, axially and/or in the circumferential direction in the encapsulation body in such a manner that the stator is secured radially, axially and/or in the circumferential direction in the encapsulation body. In addition, it is possible to reduce the variety of designs required for the stator housing. For example, a single stator housing design may be sufficient for different power variants.
In refinements of the stator arrangement, the encapsulation body can be form-fittingly connected to the stator housing via one or more undercuts in order to secure the stator in the axial direction.
Expressed alternatively, the one or more undercuts can be configured to fix the stator in the axial direction. In order to be able to fix the stator in the axial direction, the undercuts have to comprise corresponding wall portions which are at least partially inclined relative to the axial direction in order thereby to absorb axial forces.
In refinements of the stator arrangement, at least one of the one or more undercuts can be formed in the circumferential portion.
In refinements of the stator arrangement, the stator housing can comprise an axial end wall. The axial end wall can extend away from the circumferential portion in the radial direction. The encapsulation body can extend in the axial direction from the stator to the axial end wall. In refinements, the axial end wall can extend from the circumferential portion outward in the radial direction (in particular in a radial flux motor having an external rotor). Alternatively, in particular in the case of a radial flux motor having an internal rotor, the axial end wall can extend from the circumferential portion radially inward in the radial direction.
In refinements, the circumferential portion can have a first (rear) axial end. At the first axial end, the axial end wall can extend away from the circumferential portion in the radial direction. A second axial (front) end lying axially opposite the first axial end can be free-standing, and therefore the stator can be pushed over said second axial end onto the circumferential portion and accommodated.
In refinements of the stator arrangement, at least one of the one or more undercuts can be formed in the axial end wall and/or in the circumferential portion. In particular, at least one undercut can be arranged in the corner region between the axial end wall and the circumferential portion. Expressed in other words, at least one undercut can be at least partially arranged in both the axial end wall and the circumferential portion.
In refinements of the stator arrangement, the axial end wall can be substantially annular.
In refinements of the stator arrangement, the circumferential portion can be a first circumferential portion. The stator housing can furthermore comprise a second circumferential portion. The second circumferential portion can be arranged spaced apart from the first circumferential portion in the radial direction. The encapsulation body can extend in the radial direction from the first circumferential portion to the second circumferential portion. In particular, the second circumferential portion can be arranged spaced apart outward in the radial direction from the first circumferential portion (in particular in a radial flux motor having an external rotor). Alternatively, in particular in the case of a radial flux motor having an internal rotor, the second circumferential portion can be arranged spaced apart inward in the radial direction from the first circumferential portion.
In refinements of the stator arrangement, at least one of the one or more undercuts can be formed in the second circumferential portion. In refinements of the stator arrangement, at least one of the one or more undercuts can be arranged in the second circumferential portion and/or in the axial end wall. In particular, at least one undercut can also be arranged in the corner region between the axial end wall and the second circumferential portion. Expressed in other words, at least one undercut can be at least partially arranged in both the axial end wall and the second circumferential portion.
In refinements of the stator arrangement, the first circumferential portion and/or the second circumferential portion can extend away from the axial end wall in the axial direction. In particular, the first circumferential portion can extend axially away from a radially inner end of the axial end wall (in particular in a radial flux motor with an external rotor). In particular, the second circumferential portion can extend axially away from a radially outer end of the axial end wall (in particular in a radial flux motor with an external rotor). Vice versa, in an internal rotor, the first circumferential portion would extend away axially from a radially outer end of the axial end wall and the second circumferential portion from a radially inner end of the axial end wall.
In refinements of the stator arrangement, at least one of the one or more undercuts can be formed by a surface, which is inclined with respect to the axis of rotation, in the first circumferential portion and/or the second circumferential portion.
In refinements of the stator arrangement, at least one of the one or more undercuts can be formed by a depression in the stator housing, in which depression the encapsulation body engages. In particular, a plurality of depressions can be provided which are spaced apart radially and/or axially and/or in the circumferential direction and form corresponding multiple undercuts. In particular, the depression can have rounded (not sharp-edged) delimitations and/or edges and/or corners. By this means, flow into it during the encapsulation can be improved. In addition, the risk of tension cracks can thereby be reduced. In refinements of the stator arrangement, the depression or the undercut can be groove-shaped. In refinements of the stator arrangement, the depression or the undercut can extend substantially annularly in the circumferential direction in the stator housing. In particular, annular may also include in the shape of an annular portion. Expressed in other words, this can be understood as meaning an intermittent groove. In refinements, the depression or the undercut can extend over a range of approximately 5° to approximately 360º.
In refinements of the stator arrangement, the stator can be arranged at least partially in contact in the radial direction with the circumferential portion. In particular, the stator can lie with an inner circumferential surface on a radially outer surface of the (first) circumferential portion (in particular in a radial flux motor with an external rotor). Alternatively, in particular in the case of a radial flux motor with an internal rotor, the stator can lie at least partially in contact in the radial direction by means of an outer circumferential surface on a radially inner surface of the circumferential portion.
In refinements of the stator arrangement, the circumferential portion can comprise at least one web. The stator can be arranged in the radical direction so as to be at least partially in contact with the at least one web. Expressed in other words, the at least one web forms a radially outer surface of the circumferential portion, on which the stator lies. At least one of the at least one web can be formed in the circumferential portion of the stator housing. Alternatively or additionally, at least one, a plurality or all of the webs of the at least one web can be arranged or fastened as separate elements on the circumferential portion. For example, the webs can be formed by sleeves, in particular plastic sleeves (e.g. PTFE sleeves) which are pushed onto the circumferential portion. In summary, the circumferential portion can comprise at least one web which is defined by the circumferential portion or by a separate element.
In refinements of the stator arrangement, the at least one web can extend in the circumferential direction. In particular, the at least one web can extend completely, in sections or intermittently in the circumferential direction. In sections or intermittently should be understood in such a manner that the web, by means of one or more web portions which are interrupted in the circumferential direction, forms an annular or cylindrical supporting surface for the stator, which supporting surface can serve in particular for centering the stator.
In refinements of the stator arrangement, the circumferential portion can comprise two axially spaced-apart webs for receiving the stator. In particular, the stator can rest with two axially opposite end regions of the stator laminated core on the webs.
In refinements, the webs can have different outer circumferences. In refinements, the front web can have a smaller outer circumference or outer diameter than the rear web. For example, an outer diameter of the front web can be 0.1 mm to 2 mm, preferably 0.2 mm to 1.5 mm, and particularly preferably 0.5 mm to 1 mm smaller than the rear web. By this means, on the one hand, better mountability of the stator, in particular the stator laminated core, on the circumferential portion can be ensured and, on the other hand, so too can a firm fit and good centering. In particular, the stacking of the stator laminations to form a stator laminated core mean that minimal radial displacements of individual laminations can arise, as a result of which the inner diameter of the entire stator laminated core is not uniform. By means of a front web having a smaller diameter, tolerances, in particular during the installation, can more easily be compensated for. The rear web can remain here in accordance with the desired fit, for example press fit. Simple installation and a firm fit of the stator are therefore achieved at the same time. While the refinements having different diameters afford certain advantageous technical effects, it goes without saying that, in alternative refinements, the webs can also have an identical outer radius or diameter.
In some refinements, it is also possible to provide more than two axially spaced-apart webs.
In refinements having at least two webs, at least one web can extend in the axial direction over a maximum of 25%, preferably a maximum of 15%, and particularly preferably over a maximum of 5% of an entire axial width of a stator laminated core of the stator. By this means, in comparison to an axially broader web, the advantage arises that the mountability and/or the fit of the stator is improved because of, for example, manufacturing/installation tolerances of the stator laminated core. This is also advantageous in particular if both webs in refinements having two webs extend over a maximum of 25%, preferably a maximum of 15%, and particularly preferably over a maximum of 5% of an entire axial width of a stator laminated core of the stator.
In refinements of the stator arrangement, a depression into which the encapsulation body projects and forms an undercut can be formed between the two webs. In addition to the axial securing by the undercut, the depression which is filled with the material of the encapsulation body leads in a synergetically advantageous manner to an improvement in the heat dissipation from the stator into the circumferential portion. In more pronounced terms, better thermal connection can be achieved in comparison to a design without a depression or without solid material therein. In refinements, the encapsulation body can substantially completely fill the depression. In particular, the formation of bubbles in the encapsulation body or during the encapsulation can be prevented or at least reduced by the formation of the depression and/or by the provision of the webs. In exemplary refinements, the depression can have a radial depth in comparison to the webs of, for example, 0.01 mm to 1.0 mm, preferably of 0.05 mm to 0.5 mm, and particularly preferably of 0.1 mm to 0.25 mm. In refinements having different web diameters, the radial depth can be measured in particular relative to the web having the smaller diameter. Alternatively or additionally, at least one of the webs can have a radial height in comparison to the depression next to the corresponding web of, for example, 0.01 mm to 1.0 mm, preferably of 0.05 mm to 0.5 mm, and particularly preferably of 0.1 mm to 0.25 mm. As already mentioned, one or more further webs can also be arranged in the depression. Expressed alternatively, this means that the depression can be formed by a plurality of partial depressions between respectively adjacent webs.
In refinements, the depression can extend annularly in the circumferential direction.
In refinements, the depression can extend in the axial direction over at least 25%, preferably over at least 50%, and particularly preferably over at least 75% of an entire axial width of a stator laminated core of the stator. Analogously, in the case of more than two webs, i.e. in refinements having a depression which comprises a plurality of axially extending partial depressions, it is advantageous if the partial depressions together extend over at least 25%, preferably over at least 50%, and particularly preferably over at least 75% of an entire axial width of a stator laminated core of the stator. These features can result in a further improvement in the connection between the stator and stator housing in a thermal and structural respect. A wide depression is particularly advantageous with two narrow webs.
In refinements of the stator arrangement, the stator can be arranged in contact in the axial direction with a radially protruding offset of the circumferential portion. In particular, the offset can protrude outward in the radial direction from the circumferential portion (in particular in a radial flux motor having an external rotor). Alternatively, in particular in the case of a radial flux motor having an internal rotor, the offset can protrude inward in the radial direction from the circumferential portion.
In particular, the offset can serve as an axial stop for the stator, in particular for the stator laminated core thereof. Expressed in other words, the offset is in the form of a step. Together with the at least one web, a positionally precise placing of the stator can be ensured. This positioning can be fixed by the encapsulation body. In particular, the stator laminated core of the stator can lie axially on the offset.
In refinements, the axial stop can be arranged axially between the at least one web and the axial end wall. In particular, a radial depression in the first circumferential portion can be arranged axially between the axial stop and the axial end wall.
In refinements of the stator arrangement, the offset can at least partially extend in the circumferential direction. In refinements, the offset can extend completely in the circumferential direction. In exemplary refinements, the offset can extend approximately 5° to approximately 360° in the circumferential direction. In refinements, the offset can also be formed intermittently, for example. For example, an offset extending for 15° can be arranged every 30° in the circumferential portion.
In refinements, the stator arrangement can furthermore comprise a rotation lock. In refinements, the rotation lock can be formed by engagement of the stator and/or of the encapsulation body in the stator housing. In refinements, the rotation lock can be formed by at least one groove which extends in the axial direction in the circumferential portion and in which the stator and/or the encapsulation body engages. In refinements, the groove can be introduced, for example, radially inwardly into an outer circumferential surface of the circumferential portion. Alternatively, the groove can also be introduced radially outward into an inner circumferential surface of the second circumferential portion. In particular, the stator laminated core can engage in the groove. For this purpose, the stator laminated core can comprise a corresponding elevation on the inner diameter or on the outer diameter, the elevation projecting into the groove.
In refinements of the stator arrangement, the stator can comprise an annular stator laminated core. The stator laminated core can comprise a plurality of stator teeth and a plurality of electric windings which are in each case wound around the stator teeth.
In refinements, the stator can furthermore comprise a casing which is arranged between the stator laminated core and the electric windings. In refinements, the casing can comprise a first axial end cap and a second axial end cap. The end caps can be arranged at opposite axial ends of the stator laminated core. In particular, the end caps can be annular. In particular, the end caps can be electrically insulating.
In refinements, the stator arrangement can furthermore comprise an interconnecting disc. The interconnecting disc can be designed for guiding the electric windings away from the stator. In refinements, the interconnecting disc can be arranged axially between the stator and the axial end wall. In particular, the interconnecting disc can be embedded in the encapsulation body. The interconnecting disc makes it possible to realize a space-saving integration and insulation of the connection on the side of the stator in the direction of the inverter space. Even if the interconnecting disc is an advantageous refinement, alternative different solutions are also conceivable, for example a printed circuit board (PCB) or a Lead Frame.
In refinements, the encapsulation body can comprise a resin material. In particular, the encapsulation body can comprise a synthetic resin material. In refinements, the encapsulation body can comprise particles promoting heat conduction. In particular, the particles promoting heat conduction can be produced from a non-metallic material. As a result, an impairment of the electric and/or magnetic insulation effect of the encapsulation body can be prevented or at least reduced. For example, the encapsulation body can comprise glass fibers.
The present invention furthermore relates to a radial flux motor for a fan, wherein the radial flux motor comprises a stator arrangement in accordance with any of the preceding refinements. In addition, the radial flux motor comprises a motor housing, a rotor and a shaft, which is mounted rotationally in the motor housing. The rotor is arranged for conjoint rotation on the shaft in the motor housing. The stator of the stator arrangement is arranged radially adjacent to the rotor in the motor housing.
In refinements of the radial flux motor, the rotor can be formed externally. Furthermore, the rotor can comprise a plurality of permanent magnets. The plurality of permanent magnets can be arranged distributed in the circumferential direction on a rotor body of the rotor. The rotor body of the rotor can be in particular pot-shaped.
In refinements of the radial flux motor, the motor housing can comprise a rotor housing and the stator housing. The rotor housing and the stator housing can be interconnected with a force fit.
The present invention furthermore relates to a high-voltage fan. The high-voltage fan comprises a radial flux motor in accordance with any of the preceding refinements. In addition, the high-voltage fan comprises a fan impeller. The fan impeller is arranged for conjoint rotation on the shaft outside the motor housing.
The present invention furthermore relates to a cooling system for a fuel cell drive or a battery-electric drive. The cooling system comprises a cooling circuit, a heat exchanger, and a high-voltage fan in accordance with the preceding refinement. The high-voltage fan is designed and arranged to extract heat from the cooling circuit via the heat exchanger. In particular, the cooling system can be designed for use in a fuel cell, a battery and/or in an electric traction motor.
The present invention furthermore relates to a method for producing a stator arrangement for a radial flux motor. The method comprises the following steps. Providing a stator housing of a motor housing of the radial flux motor, the stator housing defining a circumferential portion for receiving the stator. Providing a stator. Pushing the stator onto the circumferential portion and placing a bell-shaped encapsulation thereon such that the stator is completely surrounded by the bell-shaped encapsulation and the stator housing. Encapsulating the stator in a horizontal position by filling encapsulation compound between the stator and the stator housing and/or the bell-shaped encapsulation. In the process, by curing of the encapsulation compound, an encapsulation body is provided which is form-fittingly connected to the stator housing in such a manner that the stator is secured at least in the axial direction in the stator housing by the encapsulation body. A horizontal position can be understood here as meaning an orientation of the stator arrangement in which the axial direction is opposed to the weight force. Expressed in other words, the weight force in the horizontal position points in the axial direction with respect to the end wall.
In refinements of the method, the stator can be wound with electric windings before being pushed onto the circumferential portion and can be pushed thereon as a wound stator.
In refinements of the method, the wound stator can be potted with the encapsulation compound and thereby fixed in the encapsulation body after curing of the encapsulation compound.
In refinements of the method, the encapsulation compound can be cast into one or more depressions which are recessed in the stator housing, in order, after the curing of the encapsulation compound, to produce the form-fitting connection to the stator receiving portion.
In refinements of the method, a resin material can be used as the encapsulation compound. In particular, a synthetic resin material can be used as the encapsulation compound. The resin material or the synthetic resin material can optionally be provided with fillers promoting heat conduction.
Further features can be seen from the accompanying drawings, which form part of this disclosure. The drawings are intended to further explain the present disclosure and to enable a person skilled in the art to put the present disclosure into practice. However, the drawings are to be understood as non-limiting examples. Common reference signs in various figures indicate identical or similar features.
Refinements of the stator arrangement, the radial flux motor, the high-voltage fan, the cooling system, and the method according to the present disclosure are explained below with reference to the drawings.
In the context of this application, the terms axial or axial direction relate to an axis of rotation 100a of the radial flux motor 100 or to a central axis 100a of the stator arrangement 10 and the stator 40, said central axes being arranged concentrically with respect to the axis of rotation 100a. Since the respective axes 100a of the stator 40, the stator arrangement 10, and the radial flux motor 100 are identical, they are depicted by the same reference sign. Depending on to which element or to which entity reference is being made, the (central) axis 100a or the axis of rotation 100a may be described in conjunction with the stator 40, the stator arrangement 10, and/or the radial flux motor 100 and/or further elements or entities, for example the rotor 130, the shaft 120, or the fan 1. In the figures (see, e.g.
In the illustration of
With further reference to
The refinements of the radial flux motor 100 that are shown in all of the figures relate to a radial flux motor 100 having an external rotor 130. As described above in the section regarding the background of the invention, the rotor 130 is arranged radially outside the stator 40 or surrounds the stator 40 radially on the outside. As can be readily seen in particular in
With further reference to
The stator 40 and the stator arrangement 10 surrounding the latter will be discussed in greater detail below. In conjunction with further elements of the radial flux motor 100, the stator arrangement 10 for the radial flux motor 100 is depicted in the right part of
The stator housing 20 defines a circumferential portion 30 for receiving the stator 40. The circumferential portion 30 should be understood as meaning a housing portion or housing region of the stator housing 20. The stator 40 is arranged on the circumferential portion 30. In more precise terms, the stator 40 is arranged on the circumferential portion 30. As shown in the figures, the circumferential portion 30 is formed substantially cylindrically, in particular substantially circular-cylindrically. For this reason, the circumferential portion is also referred to below as the cylindrical circumferential portion 30. This should also be understood as meaning cylindrical housing portions which comprise one or more flattened portions and/or depressions and/or recesses on the outer circumference and/or on the inner circumference. According to the present disclosure, flattened portions and/or depressions and/or recesses of this type can be filled with compound of the encapsulation body 50. For example, the circumferential portion 30 can have a circular-cylindrical shape at least in one or more portions, in order to define the supporting surface for the stator 40. Expressed in other words, the stator 40 surrounds the cylindrical circumferential portion 30. In addition, the stator 40 is encapsulated in the stator housing 20. The encapsulation body 50 is form-fittingly connected to the stator housing 20 in such a manner that the stator 40 is secured at least in the axial direction 2 in the stator housing 20 by the encapsulation body 50. By fastening the stator 40 by means of the encapsulation body 50, the stator holding force can be cost-efficiently improved. In addition, greater efficiency in comparison to a screwed solution can be achieved because of smaller power losses in the stator core. In particular in comparison to alternative, in particular mechanical, fastening solutions, such as the use of a snap ring, screws with segments for clamping purposes or in the form of a complete ring instead of individual segments, the required number of parts can be reduced and the production process simplified. For example in comparison to a screwed solution, apart from inserting and encapsulating the stator 40, no additional production and installation steps are required. The encapsulation body 50 is formed by encapsulating the stator 40 in the stator housing 20. In particular, the stator 40 is fixed in the encapsulation body 50, in particular with a form fit and/or frictional lock. In particular, the stator 40 is at least partially embedded radially 4, axially 2 and/or in the circumferential direction 6 in the encapsulation body 50 in such a manner that the stator 40 is secured radially 4, axially 2 and/or in the circumferential direction 6 in the encapsulation body 50 (see
As can be seen in particular in
As in the exemplary refinements of
The (first) cylindrical circumferential portion 30 can have a first (rear) axial end. At the first axial end, the axial end wall 22 can extend away from the cylindrical circumferential portion 30 in the radial direction 2 (in particular radially outward). Furthermore, the (first) cylindrical circumferential portion 30 can have a second (front) axial end lying axially opposite the first axial end. In refinements, the second axial end can be free-standing. During the installation, the stator 40 can be pushed over the second axial end onto the cylindrical circumferential portion 30 and accommodated. In this regard,
As already mentioned, the axial end wall 22 can extend away from the cylindrical circumferential portion 30 in the radial direction 4. In the exemplary embodiment of a radial flux motor 100 that is illustrated in
The second cylindrical circumferential portion 24 can be arranged spaced apart in the radial direction 4 from the first cylindrical circumferential portion 30. In the exemplary embodiment of a radial flux motor 100 that is illustrated in
As can furthermore be seen in the figures (in particular
As already mentioned, the stator housing 20 is connected via a flange to the rotor housing 112 via its flange. It can be seen from
In the refinement example illustrated (see in particular
At least in an axially rear region of the stator housing, the first cylindrical circumferential portion 30, the axial end wall 22 and the second cylindrical circumferential portion 24 form an annular axial depression. Expressed in other words, the three portions 22, 24, 30 of the stator housing 20 form an axial depression which extends in the circumferential direction 6. This depression can readily be seen at the position of the reference sign for the axial end wall 22 in
In particular with reference to
In refinements, the encapsulation body 50 can comprise a resin material. In particular, the encapsulation body 50 can comprise a synthetic resin material. In refinements, the encapsulation body 50 can comprise particles promoting heat conduction. In particular, the particles promoting heat conduction can be produced from a non-metallic material. As a result, an impairment of the electric and/or magnetic insulation effect of the encapsulation body 50 can be prevented or at least reduced. For example, the encapsulation body 50 can comprise glass fibers.
As already mentioned with reference to
In principle, one or more undercuts 52, 53, 54, 55, 56 and depressions 32, 23, 34, 25, 36 can be formed in the first cylindrical circumferential portion 30 and/or in the axial end wall 22 and/or in the second cylindrical circumferential portion 24. In principle, features which are explained with respect to a certain undercut 52, 53, 54, 55, 56 can also be used on other undercuts (shown and not shown), if technically expedient.
In
Alternatively or additionally, one or more undercuts can also be formed in a corner region between the axial end wall 22 and the second cylindrical circumferential portion 24. This also applies analogously to the corner region between the axial end wall 22 and the first cylindrical circumferential portion 30. Expressed in other words, at least one undercut can be at least partially arranged in both the axial end wall 22 and the cylindrical circumferential portion (the first circumferential portion 30 or the second circumferential portion 24).
Alternatively or additionally to the depression 25, an undercut in the second cylindrical circumferential portion 24 can be formed by a surface, which is inclined with respect to the axis of rotation 100a, in the second cylindrical circumferential portion 24. This can be a partial surface of the inner circumferential surface of the second cylindrical circumferential portion 24 or the entire inner circumferential surface. In order to achieve axial securing, the inclined surface of the second cylindrical circumferential portion 24 has to have an angle smaller than 90° relative to the axial end wall 22 or its end surface facing the stator 40 (if said end surface extends in precisely the radial direction 4). This analogously also applies to the first cylindrical circumferential portion 30 and its outer circumferential surface which, at least in a partial surface, can have an angle of smaller than 90° relative to the axial end wall 22 (if the latter extends in exactly the radial direction).
As shown by way of example in
Again with reference to
As already explained, the stator 40 can be arranged on the first cylindrical circumferential portion 30. In particular, the stator 40 can be arranged so as to be at least partially in contact in the radial direction 4 with the cylindrical circumferential portion 30. In particular, the stator 40 can lie with an inner circumferential surface on a radially outer surface of the first cylindrical circumferential portion 30 (in particular in a radial flux motor 100 having an external rotor 130). Alternatively, in particular in the case of a radial flux motor having an internal rotor, the stator 40 can lie so as to be at least partially in contact in the radial direction 4 with an outer circumferential surface on a radially inner surface of the cylindrical circumferential portion (not depicted). “At least partially in contact” should be understood as meaning that, because of manufacturing tolerances, it is not necessarily ensured that the entire circumference of the stator 40 is fully in contact with the circumferential portion 30. However, it can be understood in such a manner that the at least partially contacting arrangement is designed for the radial mounting and for the centering of the stator 40.
As can be gathered in particular from
As can be seen in particular in
The two webs 35, 37 can be in particular spaced apart axially. The intermediate web depression 34 already mentioned above can be formed axially between the two webs 35, 37. In particular, the encapsulation body 50 can project into the depression 34 and form the undercut 54. In particular, the stator 40 can rest with two axially opposite end regions of the stator laminated core 42 on the webs 35, 37. In addition to the axial securing by means of the undercut 54, the depression 34 which is filled with the material of the encapsulation body 50 leads in a synergetically advantageous manner to an improvement in the heat dissipation from the stator 40 into the first cylindrical circumferential portion 30. In more precise terms, better thermal connection can be achieved in comparison to a design without a depression or without solid material (i.e. the encapsulation body 50). In refinements, the encapsulation body 50 can substantially completely fill the depression 34. In particular, by means of the formation of the depression 34 and/or by the provision of the webs 35, 37, the formation of bubbles in the encapsulation body 50 or during the encapsulation can be prevented or at least reduced. In exemplary refinements, the depression 34 can have a radial depth in comparison to the webs 35, 37 of, for example, 0.01 mm to 1.0 mm, preferably of 0.05 mm to 0.5 mm, and particularly preferably of 0.1 mm to 0.25 mm. In refinements having different web diameters, the radial depth can be measured in particular relative to the web 37 having the smaller diameter. In particular, the radial depth can be measured in particular relative to the front web 37. Alternatively or additionally, at least one of the webs 35, 37 can have a radial height in comparison to the depression 34 next to the corresponding web 35, 37 of, for example, 0.01 mm to 1.0 mm, preferably of 0.05 mm to 0.5 mm, and particularly preferably of 0.1 mm to 0.25 mm. As already mentioned, one or more further webs can also be arranged in the depression 34. Expressed alternatively, this means that the depression 34 can be formed by a plurality of partial depressions between respectively adjacent webs.
As can be seen in particular in
In particularly advantageous refinements, the first and the second web 35, 37 extend in the axial direction 2 over a maximum of 5% of an entire axial width of a stator laminated core 42 of the stator 40. This results, in comparison to an axially wider web, in the advantage that the mountability and/or the fit of the stator 40 is improved because of, for example, manufacturing/installation tolerances of the stator laminated core 42. This is also advantageous in particular if at least the first (rear) web 35, which is arranged closer to the axial end wall 22, extends at maximum over 5% of an entire axial width of a stator laminated core 42 of the stator 40. In alternative and also advantageous refinements, one or both webs 35, 37 can extend over at maximum 25% or preferably at maximum 15% of an entire axial width of a stator laminated core 42 of the stator 40.
In particularly advantageous refinements, the depression 34 can extend in the axial direction 2 over at least 25%, preferably over at least 50%, and particularly preferably over at least 75% of an entire axial width of a stator laminated core 42 of the stator 40. Analogously in the case of more than two webs, i.e. in refinements having a depression 34 which comprises a plurality of axially extending partial depressions, it is advantageous if the partial depressions extend together over at least 25%, preferably over at least 50%, and particularly preferably over at least 75% of an entire axial width of a stator laminated core 42 of the stator 40. These features can result in a further improvement of the connection (via the encapsulation body 50) between the stator 40 and stator housing 20 in a thermal and structural respect. A wide depression 34 is particularly advantageous with two narrow webs 35, 37.
In refinements, the two webs 35, 37 can have different outer circumferences. In refinements, the front web 37 can have a smaller outer circumference or outer diameter than the rear web 35. For example, an outer diameter of the front web 37 can be 0.1 mm to 2 mm, preferably 0.2 mm to 1.5 mm, and particularly preferably 0.5 mm to 1 mm smaller than the rear web 35. By this means, firstly, better mountability of the stator 40, in particular of the stator laminated core 42, on the first cylindrical circumferential portion 30 can be ensured, as can, on the other hand, a firm fit and good centering. In particular, the stacking of the stator laminations to form a stator laminated core 42 can result in minimal radial displacements of individual laminations, as a result of which the inner diameter of the entire stator laminated core 42 is not always precisely uniform. By means of a front web 37 having a smaller diameter, tolerances, in particular during the installation, can be more easily compensated for. The rear web 35 can remain here in accordance with the desired fit, for example press fit. Simple installation and a firm fit of the stator 40 are therefore achieved at the same time. While the refinement having different diameters affords certain advantageous technical effects, it is understood that, in alternative refinements, the webs 35, 37 can also have an identical outer radius or diameter.
As is shown in particular in
In particular, the offset 33 can serve as an axial stop for the stator 40, in particular for its stator laminated core 42. Expressed in other words, the offset 33 is in the form of a step. Together with the at least one web 35, 37, positionally precise placing of the stator 40 can be ensured. This positioning can be fixed by the encapsulation body 50. In particular, the stator laminated core 42 of the stator 40 can lie axially on the offset 33.
In refinements, the axial stop 33 can be arranged axially between the at least one web 35, 37 and the axial end wall 22. In particular, the first radial depression 32 in the first cylindrical circumferential portion 30 can be arranged axially between the axial stop 33 and the axial end wall.
In refinements of the stator arrangement 10, the offset 33 can at least partially extend in the circumferential direction 6. In refinements, the offset 33 can completely extend in the circumferential direction 4. In exemplary refinements, the offset 33 can extend approximately 5° to approximately 360° in the circumferential direction 6. In refinements, the offset 33 can also be intermittent, for example. For example, an offset extending for 15° can be arranged every 30° in the cylindrical circumferential portion 30.
In refinements, the stator arrangement 10 can furthermore comprise a rotation lock 70. In refinements, the rotation lock 70 can be formed by engagement of the stator 40 and/or of the encapsulation body 50 in the stator housing 20 (see in particular
In refinements, the stator 40 can furthermore comprise a casing 44 which is arranged between the stator laminated core 42 and the electric windings 46 (see in particular
In refinements, the stator arrangement 10 can furthermore comprise an interconnecting disc 48. The interconnecting disc 48 can be designed for guiding the electric windings 46 away from the stator 40. In refinements, the interconnecting disc 48 can be arranged axially between the stator 40 and the axial end wall 22. In particular, the interconnecting disc 48 can be embedded in the encapsulation body 50. Space-saving integration and insulation of the connection on the side of the stator 40 in the direction of the inverter space can be realized by the interconnecting disc 48.
The inverter space can be arranged, for example, axially next to the axial end wall 22. In refinements, for this purpose, the axial end wall 22 can have a passage (not depicted) in the axial direction 2, as seen to the right in
The present disclosure furthermore relates to a method for producing a stator arrangement 10 for a radial flux motor 100 (see
In refinements of the method, the stator 40 can be wound with electric windings 46 before being pushed 330 onto the cylindrical circumferential portion 30 and can be pushed thereon as a wound stator 40.
In refinements of the method, the wound stator 40 can be potted with the encapsulation compound and thereby fixed in the encapsulation body 50 after the encapsulation compound has cured.
In refinements of the method, the encapsulation compound can be cast into one or more depressions 32, 23, 34, 25, 36 which are recessed into the stator housing 20, in order, after the curing of the encapsulation compound, to produce the form-fitting connection to the stator housing 20. In particular, one or more undercuts 52, 53, 54, 55, 56 can be formed in the process.
In refinements of the method, a resin material can be used as the encapsulation compound. In particular, a synthetic resin material can be used as the encapsulation compound. The resin material or the synthetic resin material can optionally be provided with fillers promoting heat conduction.
Although the present invention has been described above and is defined in the attached claims, it should be understood that the invention can alternatively also be defined in accordance with the following embodiments:
| Number | Date | Country | Kind |
|---|---|---|---|
| 10 2023 119 282.5 | Jul 2023 | DE | national |
