PERMANENT MAGNET AND METHOD FOR MANUFACTURING A ROTOR OF A DYNAMOELECTRIC MACHINE WITH SUCH PERMANENT MAGNETS

Description

[0001] The invention relates to a permanent magnet, a method for manufacturing a rotor with such permanent magnets and a dynamoelectric machine with such a rotor as well as a use of such a dynamoelectric machine.

[0002] Rotors, for example those of synchronous motors, especially for industrial applications, are typically constructed with embedded permanent magnets. For this purpose, axially extending recesses are provided in the rotor lamination stack, into which the permanent magnets are axially inserted. To facilitate assembly, the height of the permanent magnet is manufactured to be slightly less than the height of the magnet pocket – primarily in the radial direction – resulting in gaps between the magnets.

[0003] The permanent magnets are usually fixed in the recess using an adhesive or potting compound. The permanent magnets are glued to their outer surface, so that the joint, among other things, contains the adhesive.

[0004] There are various methods and bonding techniques. The following methods are known.

[0005] The magnet pockets in the rotor lamination stack are pre-fitted with the permanent magnet. A low-viscosity adhesive is then applied to the end face, which, due to gravity, seeps or capillaries into the joint gaps, thus bonding the permanent magnet in place. It is unavoidable that some adhesive will seep out onto the other end face and potentially into the flux barriers. To prevent contamination of the tooling, silicone sheets or discs are used as separators. Additionally, this technique involves preheating the rotor lamination stack to achieve a lower viscosity of the adhesive, thereby promoting capillary action into the joint gap.

[0006] In another method, the magnetic pockets are partially filled with adhesive beforehand. The permanent magnets are then inserted, displacing the adhesive and embedding the magnet within it. Here, the tool is coated with a protective layer, primarily silicone, making it easy to clean the adhesive-covered surface after the joining process. Excess adhesive is then wiped off. However, this method inevitably results in the flux barriers located on the sides of the magnetic pockets also being inadvertently filled with adhesive, leading to increased and unpredictable adhesive consumption. To accelerate the curing of the adhesive, subsequent thermal processes, such as oven curing, are often employed.

[0007] Another method is described in DE 10 2012 215 084 A1. In this method, potting compound is supplied to the recesses of the rotor's lamination stack via additional cover discs on the end faces.

[0008] Another procedure is described in WO 2018 / 206328 A1.

[0009] Based on this, the invention aims to create a rotor for a dynamo-electric machine, in particular a permanent magnet synchronous machine, which is easy to manufacture and avoids the aforementioned disadvantages.

[0010] The problem can be solved by using a permanent magnet with a cuboid-shaped basic structure for a rotor of a dynamo-electric machine, in particular a permanent magnet synchronous machine. with two opposite sides facing flux barriers (flux barrier sides), two opposite sides facing end faces (conveyor side and thrust side) and two magnetic field sides (air gap side and shaft side), wherein sections of the conveying side and / or adjoining areas of at least one side located in the magnetic flux, such as the air gap side and / or shaft side, have at least a section-by-section design, in particular a section-by-section curved / flow-engineered design.

[0011] The problem can also be solved by a method for manufacturing a rotor with buried permanent magnets according to the invention. wherein axially extending, fully enclosed recesses of a laminated core of the rotor, which recesses have a magnet pocket and flux barriers, wherein the permanent magnet is provided with two opposite sides facing flux barriers (flux barrier sides), two opposite sides facing end faces (feed side and thrust side) and two magnetic field sides (air gap side and shaft side), wherein sections of the feed side and / or adjoining areas of at least one side located in the magnetic flux, such as the air gap side and / or shaft side, have at least a section-by-section design, in particular a section-by-section curved / flow-engineering design, wherein, with the addition of adhesive to the feed side of the permanent magnet, it is inserted axially into the magnet pocket with the feed side leading and is glued there in the magnet pocket.

[0012] The problem can also be solved by a method for manufacturing a rotor with two or more laminated cores equipped according to the invention, which are axially assembled to form a total laminated core, such that, viewed axially, a staggered arrangement is present, in that the laminated cores are axially offset by a predefinable equal or different angle when viewed in the circumferential direction, whereby the angle can be 0° or up to 30°.

[0013] The problem can also be solved by a dynamo-electric machine, in particular a permanent magnet synchronous machine, with a rotor according to the invention.

[0014] The problem can also be solved by using a dynamo-electric machine according to the invention, in particular a permanent magnet synchronous machine, as a drive for pumps, fans, compressors, roller conveyors, and conveyor systems.

[0015] In order to obtain a fixing according to the invention by means of a method of permanent magnets in recesses of a laminated core of a rotor, in which it is possible to bond the permanent magnets without requiring a complex cleaning process on the end faces of the laminated core of the magnet pocket or of the tool, the permanent magnets according to the invention are first described.

[0016] The permanent magnet according to the invention has a cuboid-shaped base structure with six sides. These sides are designated as follows, also based on their subsequent use. The opposite sides of the permanent magnet, which face the flux barriers in the rotor's laminated core, are designated as flux barrier sides. The opposite sides of the permanent magnet, which are aligned axially parallel to the rotor's laminated core and face the end faces of the core, are designated as conveying or thrust sides. The opposite sides of the permanent magnet, which lie within a magnetic flux in the rotor's laminated core, are designated as air gap sides or axis sides.

[0017] According to the invention, sections of the conveying side and adjacent areas of at least one side located in the magnetic flux, i.e., either the air gap side and / or the shaft side, feature a section-by-section material removal or shaping during the manufacture of the permanent magnet, which fluidically shapes the cuboid basic structure. This shaping allows an adhesive applied to the conveying side of the permanent magnet to spread across the gaps between the air gap side and the inside of the magnet pocket, and between the shaft side and the inside of the magnet pocket, during axial movement of the permanent magnet within the magnet pocket, without wetting the flux barriers.

[0018] In other words, at least the conveying side of the permanent magnet has a hydrodynamic contour.

[0019] The edges or sections between the conveyor side and at least one magnetic field side have a flow-engineering or curved design in order to ensure sufficient adhesive distribution between the magnetic field sides and the corresponding inner sides of the magnet pockets when the permanent magnet is inserted axially into an axially running recess.

[0020] The edges exhibit planar surface elements or curved transitions from the conveyor side to at least one magnetic field side.

[0021] To ensure the distribution of the adhesive, the section between the conveyor side and the magnetic field sides is designed symmetrically.

[0022] In another embodiment, it can also be advantageous if the section between the conveying side and the magnetic field sides is designed asymmetrically, which in extreme cases can also mean that only one section between the conveying side and a magnetic field side has such designs.

[0023] In another embodiment, the conveying side can additionally feature at least one transverse channel or trough running from one side of the magnetic field to the other along the conveying side. This also serves to distribute the adhesive.

[0024] In another embodiment, the conveying side has ridges at its edges facing the flow barrier sides. These ridges contribute to adhesive distribution and prevent the adhesive from entering the flow barriers of the recesses in the rotor's lamination stack. These ridges are particularly important when the conveying side has undergone comparatively less material removal.

[0025] The walkway does not necessarily extend beyond the conveyor side, but rather forms a flat surface together with other design elements on the conveyor side.

[0026] These walkways at the edges of the conveyor side and the river dam sides are thus "remnants" of the designed cuboid basic structure. The walkways extend from one magnetic field side to the other.

[0027] The material removal or shaping on the conveying side of the permanent magnet can also extend across the entire width of one or both magnetic field sides, so that no ridges are present.

[0028] The design of the permanent magnets according to the invention relates not only to the essentially cuboid-shaped permanent magnets, but also to other designs of permanent magnets, such as bowl-shaped permanent magnets or so-called "loaf of bread" permanent magnets.

[0029] The permanent magnets can be made from rare earth elements, or they can be made from ferrite. Various coatings, such as epoxy or passivation, are also possible to prevent environmental influences, such as rust formation on the permanent magnets.

[0030] According to the invention, a method is described for fixing these permanent magnets in the recesses in the lamination stack of the rotor, in which it is possible to bond the permanent magnets in their respective magnet pockets without requiring a complex cleaning process on the end faces of the lamination stack of the magnet pocket or the tool.

[0031] A recess in the rotor's laminated core features a magnetic pocket for receiving a permanent magnet, as well as flux barriers adjoining the magnetic pocket.

[0032] Advantageously, this prevents the external flux barriers of the recesses from being filled with adhesive. This also prevents adhesive from oozing out at the end faces of the lamination stack and at the two flux barrier faces of the permanent magnet. This facilitates precise application of adhesive to each recess or magnet pocket, and thus to each rotor.

[0033] Preheating the adhesive and / or the laminated core is also unnecessary, as the adhesive is applied while the permanent magnet is moving, thus utilizing a contour-related hydrodynamic effect. Furthermore, this ensures a uniform, even adhesive layer between at least one side of the magnetic field and the corresponding side of the magnetic pocket.

[0034] The inventive method for bonding these permanent magnets proceeds as follows.

[0035] The permanent magnet according to the invention is first placed against the magnetic pocket of a recess from one side, in particular inserted approximately 2 to 3 mm. Thus, this side – the insertion side – of the magnetic pocket is covered by the contour of the conveying side of the permanent magnet, with only the flux barriers of the recess being and remaining uncovered. An additional silicone seal is not required.

[0036] An adhesive or potting compound is then applied to the feed side of the permanent magnet. This can be done through one or more nozzles, preferably in the central region of the feed side of the permanent magnet. On the feed side, the surface of the permanent magnet and adjacent areas, at least on one side within the magnetic flux (i.e., either the air gap side and / or the shaft side), has a sectional material removal or shaping feature present during the manufacturing process. This shaping allows the adhesive applied to the feed side of the permanent magnet to spread across the gaps, particularly the joining gaps between the air gap side and the inside of the magnet pocket, and between the shaft side and the inside of the magnet pocket, during axial movement of the permanent magnet within the magnet pocket, without wetting the flux barriers.

[0037] These special contours allow the adhesive to be introduced into the gap, which causes the adhesive to be distributed between the air gap side and the axis side of the permanent magnet and their corresponding inner sides of the magnet pocket during further axial displacement of the permanent magnet into the magnet pocket.

[0038] The axial movement of the permanent magnet within the magnet pocket results in a predefined adhesive distribution, which is determined by the adhesive flow rate and the axial joining speed of the permanent magnet within the magnet pocket. Adjusting the adhesive viscosity also influences the adhesive distribution in the chamfer and thus the surface area of ​​the adhesive, particularly on the air gap side and the axial side of the permanent magnet.

[0039] In one embodiment, the contour on the conveying side does not extend to the side surfaces of the permanent magnet facing the flux barriers (flux barrier sides), but is instead terminated by at least a narrow rib. This prevents the adhesive from running laterally into the flux barriers, even during axial movement of the permanent magnet into the magnet pocket, and thus becoming unavailable for the bonding process.

[0040] In another embodiment of the permanent magnets, the contour on the conveying side of the permanent magnet extends to the side surfaces of the permanent magnet facing the flux barriers (flux barrier sides).

[0041] By having at least one trough or transverse channel on the feed side of the permanent magnet, into which the adhesive is predominantly fed, it is possible to supply the gluing process with sufficient adhesive using only one nozzle. This is particularly important when the magnet height, i.e., the distance between the magnetic field faces, is greater than 4 mm.

[0042] This trough or transverse channel does not necessarily have to extend from one side of the magnetic field to the other; shorter lengths are also possible. Likewise, the cross-section of the trough or transverse channel can change from one side of the magnetic field to the other, or it can have a different contour and / or cross-sectional area.

[0043] Other geometries of the conveyor side of the permanent magnets and / or adjacent areas such as the magnetic field sides for distributing the adhesive are also possible.

[0044] It is also possible to apply different amounts of adhesive to the two chamfers and / or both sides of the magnetic field, for example by designing the chamfers differently. This allows the magnetic field sides facing the inside of the magnetic pocket to be supplied with different volumes of adhesive; for example, the air gap side of the permanent magnet could have only 30% of the adhesive volume, while the axis side of the permanent magnet could have 70%.

[0045] This method, in conjunction with the permanent magnets according to the invention, places and fixes the adhesive in predeterminable quantities within the magnetic pocket by means of a hydrodynamic effect between the permanent magnet and the inside of the magnetic pocket. The contour on the conveying side of the permanent magnet, in particular the chamfers on the permanent magnet, forms a kind of reservoir, the "fill level" of which is influenced, among other things, by the displacement speed of the permanent magnet within the magnetic pocket.

[0046] This prevents bubble formation or defects on the adhesive surfaces between a magnetic field side and the corresponding sides of the magnetic pocket of the sheet metal stack.

[0047] The special edge and chamfer geometry on the conveying side of the permanent magnet, which does not extend to the flux barrier sides, prevents the adhesive from running onto the outer surfaces of the permanent magnet and into the flux barriers. According to the invention, the flux barriers thus remain free of adhesive. Sealing the tooling of the device with silicone, particularly on the insertion side, is not required. Cleaning of the tooling and wiping of the recess opposite the insertion side are also unnecessary.

[0048] The filling / dispensing of the adhesive into the magnetic pocket on the feed side of the permanent magnet can continue continuously during the axial insertion of the permanent magnets. The nozzle and the insertion element moving the permanent magnet can be moved in parallel or synchronously, ensuring that the required volume of adhesive is maintained uniformly in the gap(s) between the inside of the magnetic pocket and the magnetic field surfaces.

[0049] To prevent the permanent magnet from slipping forward in the magnet pocket due to its magnetic tensile forces, especially in the axial direction, counter-supports of the device can be provided on the conveying side of the permanent magnet or clamps on the pushing side of the permanent magnet, so that the permanent magnet is fixed in the axial direction in the tool of the device during its insertion.

[0050] This allows for a smooth sliding process at a predetermined speed, without the permanent magnet in the magnetic pocket performing unwanted axial movements.

[0051] Once the permanent magnet is fully or almost fully inserted into the magnet pocket, the dispensing of adhesive from the nozzle is stopped. The excess adhesive droplet then washes away the chamfer, preventing any adhesive from protruding beyond the top or end face of the sheet metal stack / partial sheet metal stack.

[0052] To ensure that the rotor packages equipped with permanent magnets can be handled immediately after the assembly process without interruption, it is possible to expose the axial ends of the magnet pocket, especially the adhesive surface, to UV light after the magnet pocket has been fitted with the permanent magnet – or divided into two time-separate sections at the beginning and end of the assembly process.

[0053] The adhesive is combined with UV-curing substances. The rotor, equipped with permanent magnets, is suitable for further handling and can fully cure at room temperature.

[0054] In another version, a special nozzle is used to apply adhesive containing UV-curing substances, at least for a predefined section at the beginning and end of the process. Otherwise, in the axially central section of the magnetic pocket, the nozzle with adhesive without UV-curing substances is used.

[0055] The method according to the invention can be implemented in rotor poles that have one or more recesses per pole, and whose arrangement is tangential, V-shaped, U-shaped or double-U-shaped, etc.

[0056] The process described above is repeated for each recess in the rotor's lamination stack. After one recess has been filled, the rotor is rotated by a predetermined angle to fill the next recess in the lamination stack according to the invention.

[0057] Depending on the device used, multiple recesses of a sheet metal stack can be loaded simultaneously. It is also possible to load multiple sheet metal stacks at the same time.

[0058] The axial length of the permanent magnets corresponds to the axial length of a laminated core. To achieve axially longer rotor laminated cores, several individual cores can be combined. This allows the rotor to be constructed in a staggered fashion. Each partial laminated core is rotated relative to the axially following partial laminated core by a predefined angle in the circumferential direction.

[0059] According to this method, the permanent magnets can be inserted into the magnetic pockets magnetized, partially magnetized or unmagnetized and then later, if necessary, completely magnetized.

[0060] The permanent magnets are fed from a magazine that is oriented in such a way that the inserted permanent magnets generally lie against the radial outer side of the magnet pocket.

[0061] The permanent magnet being inserted adheres to the outside of the magnet pocket by a retaining contour in the rotor lamination. Retaining elements are provided at the edges of the magnet pocket, facing the flux barriers on the outer circumference of the rotor – i.e., the air gap of the dynamo-electric machine.

[0062] These retaining elements also increase the short-circuit strength of the dynamo-electric machine, especially a permanent magnet synchronous motor with buried permanent magnets.

[0063] Such an amplifying effect can also be achieved through tool-related measures, either instead of or in addition to the traditional method. This could involve a magnetic core to close the magnetic circuit, or additional electromagnetic coils that cause the permanent magnets to be drawn to the outside of the magnetic pocket.

[0064] The use of permanent magnets is advantageous in that the centrifugal force acting on the permanent magnets during the operation of the dynamo-electric machine is better supported by the sheet metal geometry, or the distribution of the adhesive can be aligned towards the defined gap during the manufacturing process.

[0065] Preheating of the package is not required, as with this bonding method the adhesive is wedged into the adhesive gap under hydrodynamic pressure, so that, compared to conventional methods, the high dependence of the functions of gravity, capillary action and viscosity of the adhesive is no longer present.

[0066] The features of the embodiments described so far and below can be combined in any way desired. Likewise, individual features of the respective embodiments can be combined with individual features of another embodiment without departing from the essence of the invention.

[0067] The invention and further advantageous embodiments of the invention are explained in more detail with reference to exemplary embodiments shown in principle, in which: FIG 1 Principal longitudinal section of a dynamo-electric machine, FIG 2 to FIG 6 Embodiments of permanent magnets according to the invention, FIG 7 to FIG 11 Process steps of the manufacturing process according to the invention, FIG 12, 13 Partial cross-sections of a rotor.

[0068] It should be noted that terms such as "axial," "radial," "tangential," etc., refer to the axis 6 used in the respective figure or in the described example. In other words, the directions axial, radial, and tangential always refer to an axis 6 of the rotor 9 and thus to the corresponding axis of symmetry of the stator 8. "Axial" describes a direction parallel to the axis 7, "radial" describes a direction orthogonal to the axis 6, either towards or away from it, and "tangential" is a direction that is circular around the axis 6 at a constant radial distance and with a constant axial position. The expression "circumferential" is synonymous with "tangential."

[0069] With regard to a surface, e.g. a cross-sectional area, the terms "axial", "radial", "tangential", etc. describe the orientation of the normal vector of the surface, i.e., the vector that is perpendicular to the surface in question.

[0070] The term "coaxial components," e.g., coaxial components such as rotor 9 and stator 8, refers here to components that have the same normal vectors, meaning that the planes defined by the coaxial components are parallel to each other. Furthermore, the term implies that the centers of coaxial components lie on the same axis of rotation or symmetry. However, these centers may be located at different axial positions on this axis, and the planes in question may therefore have a distance greater than zero from each other. The term does not necessarily require that coaxial components have the same radius.

[0071] The term "complementary," in the context of two components that are complementary to each other, means that their external forms are designed such that one component can preferably be completely enclosed within its complementary component, so that the inner surface of one component and the outer surface of the other ideally touch without gaps or across their entire surface. Consequently, in the case of two complementary objects, the external form of one object is determined by the external form of the other. The term "complementary" could be replaced by the term "inverse."

[0072] For the sake of clarity, in some cases where components are present multiple times, not all components shown in the figures are provided with reference symbols.

[0073] FIG 1Figure 1 shows a general longitudinal section of a dynamo-electric machine 1. In this example, a stator 8, with a winding system 7 arranged in substantially axially extending slots 16, is housed in a casing 2. The casing 2 is supported on a shaft 5 by means of bearings 4 via end shields. A rotor 9, spaced from the stator 8 by an air gap 25, is provided and has permanent magnets 14 in substantially axially extending recesses 13. Both the laminated cores 10, 11 of the stator 8 and rotor 9 can optionally have axially extending cooling channels to enable a closed internal cooling circuit within the casing 2. When the winding system 7 of the stator 8 is energized, the shaft 5 is set into rotation about an axis 6 by electromagnetic interaction with the rotor 9. This rotation drives a working machine (not shown) and an internal fan 15 in the casing 2.

[0074] Figures 2 to 6 show non-restrictive examples of permanent magnets 14 designed according to the invention, with which the method can be implemented particularly advantageously.

[0075] A permanent magnet 14, which has a cuboidal base structure, has the following sides. The permanent magnet 14 has a cuboidal base structure with six sides. The opposing sides of the permanent magnet 14, which in later use in the lamination stack 11 of the rotor 9 face the flux barriers 34, are designated as flux barrier sides 17. The opposing sides of the permanent magnet 14, which in later use in the lamination stack 11 of the rotor 9 are designated as conveying sides 18 and pusher sides 19, respectively, which are aligned with their normal vectors parallel to the axis and face the end faces of the lamination stack 11, respectively. The opposing sides of the permanent magnet 14, which in later use in the lamination stack 11 of the rotor 9 lie perpendicularly in a magnetic flux, are designated as air gap sides 23 and axis sides 24.

[0076] According to the invention, sections of the conveying side 18 and adjoining areas on at least one side located in the magnetic flux, i.e., either the air gap side 23 and / or the shaft side 24, have a section-by-section material design or material removal. This shapes the cuboid basic structure of the permanent magnet 14 in such a way that an adhesive 29 applied to the conveying side 18, when the permanent magnet 14 moves axially within the magnet pocket 40, is distributed across the gaps 41, 42 between the air gap side 23 and the magnet pocket 40, and between the shaft side 24 and the magnet pocket 40, without wetting the flux barriers 34.

[0077] In other words, at least the conveying side 18 of the permanent magnet 14 has such a hydrodynamic contour.

[0078] The edges or sections between conveyor side 18 and at least one magnetic field side 23, 24 have a flow-technical or curved design in order to obtain sufficient adhesive distribution between the magnetic field sides 23, 24 and the corresponding sides of the magnet pockets 40 in the lamination stack 11 when the permanent magnet 14 is inserted axially 30 into the axially extending recess 13.

[0079] In this area, the edges of the permanent magnets 14 have planar surface elements or curved transitions from the conveying side 18 to at least one magnetic field side 23, 24.

[0080] For the insertion of the permanent magnets 14 into the magnet pocket 40 of the lamination stack 11, the lamination stack 11 is preferably oriented horizontally such that the recesses 13 to be fitted are arranged essentially at the bottom.

[0081] According to the procedure according to the Figures 7 to 11An exemplary device for carrying out the method is shown, with each figure depicting a basic cross-section and longitudinal section of two sheet metal stacks 11. For clarity, each pole 44 is shown with only a simplified tangential recess 13. The recesses 13 themselves are arranged as follows: FIG 12 and FIG 13 The magnetic pockets 40, flux barriers 34, and optimal holding elements 33 are shown together. Likewise, each pole 44 can have several recesses 13, such as V-arrangements, U-arrangements, or double-V arrangements.

[0082] First, the permanent magnet 14 is inserted into its magnet pocket 40 approximately 2 to 3 mm from one end face, with the conveying side 18 leading ( FIG 8Thus, this insertion side of the magnetic pocket 40 is covered by the contour of the permanent magnet 14. The flux barriers 34 of the recess 13 remain uncovered. An additional silicone cover is not required. Now, adhesive 29 is applied to the conveying side 18 of the permanent magnet 14 by means of one or more nozzles 28. Ideally, this occurs at the center of this surface. Special contours are incorporated on the conveying side 18 and optionally on the adjacent areas of the air gap side 23 and / or shaft side 24. These contours ensure that the adhesive 29 is distributed across the air gap side 23 and shaft side 24 as the permanent magnet 14 is further axially displaced into the magnetic pocket 40. Ideally, the nozzle 28 and the permanent magnet 14 move synchronously in the axial direction ( FIG 9, FIG 10 ).

[0083] In other words, the axial feed 31 of nozzle 28 and the axial feed 30 of permanent magnet 14 are equal. This can be ensured, among other things, by providing an optional counter-support of the device on the conveying side 18 of the permanent magnet 14 to prevent the permanent magnet 14 from leading due to its magnetic tensile forces in the magnet pocket 40, particularly in the axial direction.

[0084] The contours of the permanent magnet 14 on the conveying side 18 can be straight or oval chamfers 20. Additionally, possibly with a channel or a recess 22 arranged transversely to the permanent magnet 14, the chamfers 20 from the conveying side 18 to the magnetic field sides 23, 24 can thus be optimally supplied with adhesive 29.

[0085] This recess makes it possible, among other things, to supply the adhesive process with sufficient adhesive 29 using only one nozzle 31 per magnetic pocket 40. This is particularly important when the magnet height (distance between the two magnetic field sides) is less than 4 mm.

[0086] Other geometries for the design of the conveying side 18 and its adjoining areas of the magnetic field sides 23, 24 for distributing the adhesive 29 are possible. For example, the two chamfers 20 can be designed differently to supply the two magnetic field sides 23, 24 with different amounts of the adhesive 29. For example, according to FIG 13 The gap 41 on the air gap side 23 of the permanent magnet 14 is supplied with only 30% of the adhesive volume, while the gap 42 on the shaft side 24 receives 70% of the adhesive volume.

[0087] The channel or trough 22 on the conveying side 18 of the permanent magnet 14 can also be inclined or closed on one side to ensure proper distribution of the adhesive 29.

[0088] This results in an adhesive distribution that is coordinated by the volume flow rate of the adhesive 29 and the axial joining speed of the permanent magnet 14 into the magnet pocket 40. Adjusting the viscosity of the adhesive 29 also influences the distribution of the adhesive 29 in the chamfer 20 and thus the surface area (magnetic field side 23, 24 facing the inside 43 of the magnet pockets 40).

[0089] It is important that the chamfer 20 does not extend to the side surfaces of the permanent magnet 14, i.e., the flux barrier sides 17. This prevents the adhesive 29 from running laterally into the flux barriers 34 during axial movement of the permanent magnet 14.

[0090] This remaining footbridge 21 thus prevents the adhesive 29 from running into the river barriers 34.

[0091] The filling of the magnetic pocket 40 with the axially moving permanent magnet 14 contained therein can therefore be continued continuously for each magnetic pocket 40. After each magnetic pocket 40 has been filled, the lamination stack 11 is rotated further by a predefinable angle 37 to fill the next magnetic pocket 40. The nozzle 28 and the insertion element, particularly as part of a placement device 38 for the permanent magnet 14, can be moved synchronously and equidistantly, so that the adhesive volume in the gaps between the magnetic field sides 23, 24 and the inner sides 41, 42 of the magnetic pocket 40 is kept uniform.

[0092] To prevent the permanent magnet 14 from slipping forward due to its magnetic tensile forces in the lamination stack 11, counter supports can be provided in the loading device 38 on the conveying side 18 of the permanent magnet 14, so that the permanent magnet 14 is fixed in the axial direction in the tool during loading.

[0093] Once the permanent magnet 14 is fully inserted into the magnet pocket 40, the dispensing of the adhesive 29 from the nozzle 28 is stopped. Any excess adhesive droplet is then washed away from the chamfer 20, thus preventing any axial protrusion of adhesive 29 beyond the end face of the laminated core 11.

[0094] To enable immediate subsequent processing of the rotor 9, each magnetic pocket 40 can optionally be exposed to UV light on its end faces, especially on the adhesive surfaces, after being fitted with its permanent magnet 14. FIG 11The light curing 32 can be carried out simultaneously or sequentially. Likewise, all end faces of the magnetic pockets 40 of a rotor 9 can also be cured simultaneously. For this purpose, the adhesive 29 must be coated with UV-curing substances. The rotor 9 is then suitable for further handling and can subsequently cure completely at room temperature.

[0095] The permanent magnets 14 are fed from a magazine 27, so that ideally the permanent magnets 14 generally lie on the radial outside of the magnet pocket 40 and the gap 41 between air gap side 23 of the permanent magnet 14 and inside 41 of the magnet pocket 40 is minimized.

[0096] The permanent magnets 14 can be inserted into the magnetic pockets 40 magnetized, partially magnetized or unmagnetized according to this procedure and then, if necessary, completely magnetized later.

[0097] The permanent magnets are fed in - as already described - from the magazine 27, which is oriented so that the permanent magnets 14 to be inserted generally lie against the inner side 43 of the magnet pocket 40 facing the outer circumference.

[0098] The adhesion of the inserted permanent magnet 14 to the outside of the magnet pocket 40 can be secured by a retaining contour of the magnet pocket 40 already in the lamination cut of the rotor lamination stack 11. Retaining elements 33 are provided at the edges of the magnet pocket 40 for the flux barriers 24, which face the outer circumference of the rotor 9 – i.e., the air gap 25 of the dynamo-electric machine 1. These retaining elements 33 also increase the short-circuit withstand capability of a dynamo-electric machine 1, in particular a permanent magnet synchronous machine with buried permanent magnets 14.

[0099] The orientation of the permanent magnets 14, which can also be influenced by the design of their conveying side 18, is advantageous in that the centrifugal force acting on the permanent magnets 14 during the operation of the dynamo-electric machine 1 can be better supported by the sheet metal geometry. Furthermore, this ensures that the distribution of the adhesive 29 during the manufacturing process of the rotor 9 is aligned with a predetermined dimension of the gap 41.

[0100] The permanent magnets 14 (air gap side 23) are advantageously located directly on the outside of the magnetic pocket 40.

[0101] Direct contact means that the permanent magnets are in direct contact with the sheet metal - only slight irregularities in the µm range are present.

[0102] On the axial side of the magnetic pocket, there is a gap of approximately 0.15 to 0.25 mm between the permanent magnet and the sheet metal.

[0103] In this method for manufacturing a rotor 9 with buried permanent magnets 14 according to the invention, the adhesive 29 is placed and fixed in the joining gaps 41, 42 between the inner surfaces 43 of the magnetic field pockets 40 and the magnetic field sides 23, 24 by means of its resulting hydrodynamic effect. The chamfers 20 on the permanent magnet 14 form a kind of reservoir for the adhesive 29, which ensures a sufficient supply of adhesive 29 during the filling process, depending on the feed rate 30 of the permanent magnet 14.

[0104] This also prevents bubble formation or defects on the adhesive surfaces between the magnetic field sides 23, 24 and the corresponding inner surfaces 43 of the magnetic pockets 40. The special contour, in particular the ribs 21, prevents the adhesive 29 from running into the flux barriers of the recesses. According to the invention, the flux barriers 34 thus remain free of adhesive 29.

[0105] Sealing the tool of the placement device 38 with silicone, particularly on the end faces of the magnetic pockets 40, is not required. Cleaning the tool and wiping the end faces is unnecessary.

[0106] Preheating of the lamination stack 11 of the rotor 9 is not required, since with this bonding method the adhesive 29 is wedged into the adhesive gaps / joining gaps 41, 42 under hydrodynamic pressure formation and the previous high dependence of the functions gravity effect, capillary action and viscosity of the adhesive when fixing the permanent magnets in the magnet pocket 40 is no longer present.

[0107] FIG 12 Figure 1 shows an exemplary partial cross-section of a rotor 9, in which, for illustrative purposes, only a magnet pocket 40 is provided with a permanent magnet 14. The rotor 9 also has inertial recesses 35 and cooling channels 36.

[0108] FIG 13shows a pole 44 with V-shaped recesses 13, where, for illustrative purposes only, a magnetic pocket 40 is also provided with a permanent magnet 14.

[0109] Columns 41 and 42 may have different levels of detail.

[0110] In order to provide axially longer rotors 9 for corresponding dynamoelectric machines 1, these laminated cores 11, equipped with permanent magnets 14, can be arranged axially one behind the other and, in particular, fixed to the shaft 5 in a rotationally fixed manner. The individual laminated cores 11 can be offset from each other circumferentially by a predefinable angle to achieve a staggered arrangement of the poles 44 of the rotor 9 over its entire axial length. This can reduce torque ripple.

[0111] Such rotors 9 are primarily used in dynamoelectric machines 1, such as permanent magnet synchronous machines, which are mainly operated in industrial environments. They are designed to drive pumps, fans, compressors, roller conveyors, and conveyor systems that require very long continuous operating times. These dynamoelectric machines 1 can also be used in traction drives such as those for mining vehicles, electric buses, trams, or trains, among other things to ensure more reliable operation by increasing the stability of the opposing magnetic field.

[0112] In principle, such dynamoelectric machines 1 can be used as motors or generators. Reference symbol list

[0113] 1 Dynamo-electric machine 2 Housing 3 Bearing shield 4 Bearing 5 Shaft 6 Axis 7 Winding system 8 Stator 9 Rotor 10 Stator lamination stack 11 Rotor lamination stack 12 Stator cooling channel 13 Rotor recess for permanent magnets 14 Permanent magnet 15 Self-rotating motor 16 Stator slots 17 Permanent magnet side face (facing flux stop) 18 Feed side of permanent magnet 19 Push side of permanent magnet 20 Chamfer 21 Web 22 Transverse channel 23 Air gap side of permanent magnet 24 Axis side of permanent magnet 25 Air gap 26 Rotor lamination stack bore 27 Magazine 28 Nozzle 29 Adhesive 30 Permanent magnet feed 31 Nozzle feed 32 Light curing 33 Mounts 34 Flux stop 35 Inertia recess 36 Cooling channel rotor 37 Direction of rotation 38 Loading device 39 Axial height of rotor lamination stack 40 Magnet pocket 41 Gap between air gap side PM and inside of magnet pocket 42 Gap between shaft side PM and inside of magnet pocket 43 Inside of magnet pocket 44 Pole

Claims

1. Method for manufacturing a rotor (9) with buried permanent magnets (14) having a base structure, in particular a cuboid base structure, for a rotor (9) of a dynamoelectric machine (1), wherein axially extending, circumferentially closed recesses (13) of a laminated core (11) of the rotor (9) have a magnet pocket (40) and flux barriers (34), wherein the permanent magnet (14) has two opposing flux-barrier sides (17) facing the flux barriers (34), two opposing sides facing end faces, namely a conveying side (18) and a pushing side (19), and two magnetic-field sides, namely an air-gap side (23) and an axial side (24), wherein portions of the conveying side (18) and / or adjoining regions of at least one side located in the magnetic flux, such as the air-gap side (23) and / or axial side (24), have sectionally curvilinear / fluid-dynamic designs, wherein, with the addition of adhesive (29) to the conveying side (18) of the permanent magnet (14), the latter is inserted axially into the magnet pocket (40) with the conveying side (18) leading and is adhesively bonded there in the magnet pocket (40), wherein an adhesive (29) applied to the conveying side (18), during axial movement of the permanent magnet (14) in the magnet pocket (40), is distributed over the gaps (41, 42) between the air-gap side (23) and the magnet pocket (40) and between the axial side (24) and the magnet pocket (40), without wetting the flux barriers (34).

2. Method for manufacturing a rotor (9) with buried permanent magnets (14) according to Claim 1, characterized in that the addition of adhesive (29) per magnet pocket (40) takes place via at least one nozzle (28), which is moved at least in sections in the magnet pocket (40) synchronously with and equidistant from the permanent magnet (14) to be inserted.

3. Method for manufacturing a rotor (9) with buried permanent magnets (14) according to either Claim 1 or Claim 2, characterized in that the joining gap (41) between the air-gap side (23) of the permanent magnet (14) and the corresponding inner side (43) of the magnet pocket (40) is set by means of the design of the conveying side (18) of the permanent magnet (14) and / or retaining elements (33) on the side of the magnet pocket (40) facing the outer circumference of the rotor (9) and / or external magnetic fields.

4. Method for manufacturing a rotor (9) with buried permanent magnets (14) according to any one or more of the preceding claims, characterized in that the permanent magnets (14) are inserted into the magnet pockets (40) in a previously magnetized, or at least partially magnetized, or unmagnetized state.

5. Method for manufacturing a rotor (9) with buried permanent magnets (14), with two or more laminated cores (11) equipped according to any one of the preceding claims, which are assembled axially into an overall laminated core in such a way that, when viewed axially, a staggering is present in that the laminated cores (11), viewed in the circumferential direction, are assembled with an axial offset by a specifiable identical or different angle, wherein the angle may be 0° or up to 30°.

6. Method for manufacturing a rotor (9) with buried permanent magnets (14) according to any one or more of the preceding claims, characterized in that at least one edge between a magnetic-field side (23, 24) and the conveying side (18) of the permanent magnet (14) is designed at least in sections.

7. Method for manufacturing a rotor (9) with buried permanent magnets (14) according to any one or more of the preceding claims, characterized in that the area or edges between a magnetic-field side (23, 24) and the conveying side (18) of the permanent magnet (14) are designed at least in sections as flat surfaces.

8. Method for manufacturing a rotor (9) with buried permanent magnets (14) according to any one or more of the preceding claims, characterized in that the area or edges between a magnetic-field side (23, 24) and the conveying side (18) of the permanent magnet (14) are designed at least in sections to be rounded.

9. Method for manufacturing a rotor (9) with buried permanent magnets (14) according to any one or more of the preceding claims, characterized in that the conveying side (18) of the permanent magnet (14) has at least one transverse channel or recess (22).

10. Method for manufacturing a rotor (9) with buried permanent magnets (14) according to any one or more of the preceding claims, characterized in that the conveying side (18) of the permanent magnet (14) has a symmetrical edge design with respect to its longitudinal axis or transverse axis.

11. Method for manufacturing a rotor (9) with buried permanent magnets (14) according to any one or more of the preceding claims, characterized in that the conveying side (18) of the permanent magnet (14) has an asymmetrical edge design with respect to its longitudinal axis or transverse axis.

12. Method for manufacturing a rotor (9) with buried permanent magnets (14) according to any one or more of the preceding claims, characterized in that the conveying side (18) of the permanent magnet (14) forms ribs (21) at its ends in the direction of the flux-barrier sides (17).

13. Dynamoelectric machine (1), in particular a permanently excited synchronous machine, having a rotor (9) manufactured according to any one of the preceding claims.

14. Use of a dynamoelectric machine (1), in particular a permanently excited synchronous machine according to Claim 13, as a drive for pumps, fans, compressors, compressor units, roller lines, and conveyor systems.