METHOD FOR PRODUCING A MATERIAL LAYER AND A MATERIAL LAYER STRUCTURE FOR A DYNAMOELECTRIC ROTATORY MACHINE

Description

[0001] The invention relates to a method for producing a material layer with a layer thickness between 0.5 and 500 µm.

[0002] The magnetic circuit of a dynamoelectric rotary machine consists of a stator and a rotor. The rotor and stator represent the power-generating components, also called active parts, of the dynamoelectric rotary machine and are currently manufactured as laminated cores.

[0003] Patent WO 2013 / 126546 A1 discloses a composition for forming a stator or a part thereof, comprising a curable elastomer, a fiber, a color dispersion compound and carbon black.

[0004] Patent EP 3 255 758 A1 discloses a rotor for a reluctance machine with conductor layers and insulation layers arranged alternately in the axial direction, wherein the conductor layers have magnetic flux-conducting conductor regions and the insulation layers are electrically insulating. The rotor is manufactured at least partially by additive manufacturing.

[0005] Today's laminated cores consist of sheets cut or punched from rolled large sheets of soft magnetic material. The sheets are then stacked together to form a laminated core.

[0006] Conventional rolling processes for large sheets cannot produce sheets thinner than 100 µm. Furthermore, cutting or punching the sheets from the large sheets generates waste.

[0007] The invention is therefore based on the object of improving the production of sheets for dynamoelectric rotary machines.

[0008] The object is achieved by a method according to claim 1, i.e. a method for producing a material layer with a layer thickness between 0.5 and 500 µm with the following steps: Applying a suspension, comprising at least one binder and solid particles, through a stencil onto a base surface to obtain a green body, expelling the binder from the green body, in particular by debinding, creating a permanent cohesion of the solid particles by heating and / or by compaction, in particular by sintering.

[0009] Furthermore, the object is achieved by a material layer according to claim 8 and a method for producing a material layer structure for a rotor of a dynamoelectric rotary device according to claim 13.

[0010] The object is further achieved by a material layer structure according to claim 15 for a rotor of a dynamoelectric rotary machine, wherein the material layer structure has a plurality of material layers arranged one above the other, a rotor of a dynamoelectric rotary machine having such a material layer structure, and a dynamoelectric rotary machine.

[0011] The material layer advantageously has the previous functions of a conventional sheet in a conventional rotor lamination stack and performs the tasks of a sheet.

[0012] Advantageously, an outline of the material layer essentially corresponds to the outline of a sheet metal.

[0013] The material layer is advantageously manufactured thinner and / or can be manufactured thinner than a sheet.

[0014] The material layer structure advantageously has the previous functions of a rotor lamination stack and performs the tasks of a rotor lamination stack.

[0015] The material layers are arranged one above the other to create the material layer structure. Preferably, the material layers are arranged in the direction of a rotational axis, in other words, along a rotational axis of the material layer structure.

[0016] Other arrangements, in which preferably at least two material layers are adjacent, are also conceivable.

[0017] The material layer preferably has a substantially round, substantially centrally arranged material recess. The material layer structure preferably has a cylindrical material recess along the rotational axis for connection to a shaft.

[0018] For a particularly stable material layer design, the material layer preferably has a layer thickness between 10 and 100 µm.

[0019] The suspension is preferably applied with a squeegee.

[0020] The suspension comprises at least one binder and solid particles that can be expelled, in particular by debinding.

[0021] The binder is preferably an organic binder. The binder is preferably such that it dissociates completely or almost completely into gaseous components upon heating.

[0022] The solid particles are preferably in powder form. A solid particle preferably comprises at least one magnetically and / or electrically conductive material.

[0023] The solid particle preferably has a diameter between 0.1 and 100 µm.

[0024] In a particular embodiment, the solid particle preferably has a diameter between 0.5 and 10 µm. The smaller the diameter of the solid particles, the thinner the material layers that can be produced. For example, a 0.5 µm thin material layer can be produced using a suspension containing solid particles with a diameter of 0.5 µm.

[0025] The powder may comprise solid particles of only one material or may be a powder mixture comprising at least two different materials.

[0026] The powder can be customized in terms of strength, magnetic characteristics, electrical characteristics and thermal conductivity.

[0027] The solid particles are permanently bonded by heating and / or compaction, in particular by sintering.

[0028] Sintering is preferably a thermal process, which depends particularly on the materials used. For example, a temperature or temperature range depends on the alloy of the material, other additives, and the desired result (after sintering).

[0029] The stencil is preferably a template for transferring desired shapes and / or outlines and / or patterns and / or cutouts, etc. The stencil can be used as often as desired.

[0030] Using the template, the desired shape of the material layer can be created. This eliminates waste. Two or more templates can also be used for one material layer.

[0031] The template can be modified quickly and inexpensively (especially faster than a punching tool).

[0032] Even delicate shapes can be reproduced from the template. Material layers with delicate shapes are particularly advantageous for lightweight construction of dynamoelectric rotary machines, cooling, and magnetic dispersion.

[0033] In a further advantageous embodiment of the invention, an insulating material is applied to the material layer on at least one side of the layer.

[0034] Preferably, the insulation material is a ceramic, in particular a non-magnetic oxide ceramic, for example zirconium oxide or aluminum oxide.

[0035] The applied insulation material preferably serves for electrical insulation.

[0036] The applied insulation material preferably serves to electrically insulate one material layer from at least one further material layer when at least two or more material layers are arranged one above the other, in particular to create a material layer structure.

[0037] The advantageously applied insulation material therefore prevents current from passing from one material layer to another.

[0038] In a further advantageous embodiment of the invention, an insulating material is applied to the material layer on both sides of the layer.

[0039] If the insulation material is applied to only one side of the material layer, the material layer is thinner. If the insulation material is applied to both sides of the material layer, the material layer is better insulated.

[0040] In a further advantageous embodiment of the invention, a varnish, in particular a baking varnish, is applied to the material layer.

[0041] The varnish, especially self-adhesive varnish, can be the insulating material. However, the varnish and the insulating material can also be two different materials.

[0042] The advantageously applied baking varnish enables particularly good electrical insulation of the material layer, in particular with respect to an adjacent further material layer in a material layer structure.

[0043] Furthermore, the material layer can be solidified with the adjacent material layer or layers, in particular by means of the baking varnish.

[0044] The advantageously applied bonding varnish enables high strength and rigidity of the material layer structure, as the material layers are bonded across the entire surface. This also reduces vibrations and noise.

[0045] In a further advantageous embodiment of the invention, the solid particles comprise particles of electrically and / or magnetically conductive material, in particular metal particles.

[0046] The electrically conductive material is preferably silver, copper, gold, aluminum, tungsten, iron, and / or steel and / or their alloys. However, other electrically conductive materials are also conceivable.

[0047] Preferably, the magnetically conductive material is a ferromagnetic material.

[0048] In a further advantageous embodiment of the invention, the solid particles comprise particles of soft magnetic material.

[0049] For example, the soft magnetic material is iron, nickel, cobalt, and / or their alloys. However, other magnetically conductive materials, especially ferromagnetic ones, are also conceivable.

[0050] In a further advantageous embodiment of the invention, the suspension is structurally viscous.

[0051] This has the advantage that the suspension is less viscous during application to the base surface to create the green body, preferably with a squeegee, and the desired shape can be optimally transferred through the stencil. Once application is complete, the green body retains the desired shape.

[0052] The invention further relates to a material layer produced in the manner described, wherein the material layer has a layer thickness between 0.5 and 500 µm, in particular between 10 and 100 µm, wherein the material layer comprises a soft magnetic material, wherein the material layer has an insulating material on at least one layer side.

[0053] In a further advantageous embodiment of the invention, the material layer has an insulating material on both sides of the layer.

[0054] In a further advantageous embodiment of the invention, the material layer comprises varnish, in particular baking varnish.

[0055] In a further advantageous embodiment of the invention, the material layer can be consolidated with at least one further material layer.

[0056] In a further advantageous embodiment of the invention, the material layer has a material recess arranged substantially centrally.

[0057] Preferably, the material recess is essentially circular. The material recess allows for connection to a shaft.

[0058] The invention also relates to a method for producing the material layer structure for the rotor of the dynamoelectric rotary machine, comprising the following steps: Additive manufacturing of a first material layer, wherein the first material layer comprises at least one material layer, applying an insulating material to the first material layer, additive manufacturing of at least one further material layer, wherein the at least one further material layer comprises at least one material layer, applying an insulating material to the at least one further material layer, joining the first and the at least one further material layer, mutually solidifying the material layers.

[0059] The material layer comprises at least one material layer, i.e., only one layer of solid particles. This makes the material layer particularly thin. However, to achieve a stable material layer, two or more material layers on top of each other are advantageous.

[0060] In a preferred embodiment, the applied insulation material is varnish, especially self-bonding varnish. Self-bonding varnish is easy to apply, and two or more layers of material can be bonded together by bonding.

[0061] The insulation material, in particular the baking varnish, and the material layer are preferably bonded together.

[0062] In an alternative embodiment, the insulation material is ceramic.

[0063] Water glass and other glasses can also be used as insulation materials.

[0064] Other insulation materials are also possible.

[0065] The application of a ceramic insulation material is particularly successful when a ceramic suspension comprising solid ceramic particles and an expellable binder is applied to the material layer with a doctor blade. The solid ceramic particles are preferably in the form of ceramic powder.

[0066] The ceramic solid particles can include magnesium oxide, titanium dioxide, silicon carbide, silicon nitride, boron carbide, boron nitride, and / or aluminum nitride. Other materials are also conceivable.

[0067] However, an oxide ceramic, in particular zirconium oxide and / or aluminum oxide, is preferred.

[0068] A ceramic solid particle preferably has a diameter substantially between 0.1 and 2 µm.

[0069] The smaller the diameter of the ceramic solid particles, the thinner the insulated material layers that can be produced. For example, using a suspension containing solid particles with a diameter of 0.5 µm and a suspension containing ceramic solid particles with a diameter of 1 µm, a 1.5 µm thin single-sided insulated material layer or a 2.5 µm thin double-sided insulated material layer can be produced.

[0070] In a particularly thin material layer design, the material layer has a layer thickness of 1 µm.

[0071] The ceramic solid particles form at least one layer of material. However, two or more layers of material are also possible.

[0072] The ceramic powder may comprise ceramic solid particles of only one material or may be a ceramic powder mixture comprising at least two different ceramic materials.

[0073] The ceramic solid particles are permanently bonded by heating and / or compaction, in particular by sintering. The ceramic solid particles are preferably permanently bonded to the solid particles by heating and / or compaction, in particular by sintering. The permanent bond is preferably a material bond.

[0074] In a further advantageous embodiment of the invention, a material layer structure is produced by means of a plurality of material layers with a layer thickness of 0.5 to 500 µm.

[0075] The material layer structure is suitable for a rotor of a dynamoelectric rotary machine, wherein the material layer structure has a plurality of material layers arranged in the direction of a rotor axis of the material layer structure.

[0076] The rotor of the dynamoelectric rotary machine has such a material layer structure.

[0077] The invention further relates to a dynamoelectric rotary machine having such a rotor.

[0078] The dynamoelectric rotary machine comprises a rotor with a plurality of material layers arranged one above the other. The material layers are preferably individually electrically insulated from one another. For this purpose, the arrangement planes are advantageously arranged parallel to the direction of the magnetic flux.

[0079] Since the material layers are very thin, eddy current losses are significantly reduced. This is because an eddy current can only develop within the thickness of the material layer, which significantly reduces the eddy current strength in thin material layers.

[0080] The insulation between the individual material layers prevents the eddy currents from superimposing themselves to form large, loss-making eddy currents.

[0081] The invention is preferably applied to dynamoelectric rotary machines. However, the invention can also be used in other energy converters, such as transformers.

[0082] The invention is also applicable to a stator of a dynamoelectric rotary machine. In this case, a plurality of stacked material layers preferably replaces a conventional stator lamination stack.

[0083] The invention is particularly suitable for engines that require high performance with low weight, especially in aircraft, helicopters and Formula E racing cars.

[0084] The invention is described and explained in more detail below with reference to the exemplary embodiments shown in the figures. They show: FIG 1 shows the method according to the invention for producing a material layer with a layer thickness between 0.5 and 500 µm, FIG 2 shows the material layer, FIG 3 shows the material layer in a side view, FIG 4 shows a method for producing a material layer structure for a rotor of a dynamoelectric rotary machine, FIG 5 shows a rotor of the dynamoelectric rotary machine and FIG 6 shows a side view of the dynamoelectric rotary machine.

[0085] FIG 1 shows the inventive method for producing a material layer with a layer thickness between 0.5 and 500 µm.

[0086] The layer thickness is preferably between 10 and 100 µm for a stable material layer.

[0087] In a process step S1, a suspension comprising at least one binder and solid particles is applied to a base surface through a stencil to obtain a green body. "Applied" preferably means: the suspension is applied to the base surface using a doctor blade.

[0088] In a process step S2, the binder is expelled from the green body, in particular by debinding.

[0089] In a process step S3, a permanent cohesion of the solid particles is created by heating and / or by means of compaction, in particular by means of sintering.

[0090] In a process step S4, insulation material is applied to one side of the layer. "Applied" preferably means: insulation material is applied to the layer side with a doctor blade, the layer side is coated with a spreading tool, or the layer side is immersed in a container containing the insulation material.

[0091] The insulation material is preferably varnish, in particular baking varnish.

[0092] However, other insulation materials are also conceivable. For example, the insulation material can be applied to the layer side using a ceramic suspension comprising at least one binder and ceramic solid particles, and the binder can be removed, particularly by debinding.

[0093] In addition, it is possible to apply an insulating material in a process step S4a (not shown) and additionally to apply varnish, in particular baking varnish, in a process step S4b (not shown).

[0094] If both sides of the layer are to be provided with insulation material and / or varnish - marked with b? and j - this is done in a process step S41.

[0095] If only one side of the layer is to be provided with insulation material and / or varnish, the material layer is completed in a process step S5 using b? and n.

[0096] FIG 2 shows material layer 1.

[0097] Material layer 1 has a layer thickness d. The material layer is preferably made in one piece.

[0098] Preferably, each material layer 1 has an insulating material on at least one side of the layer. The figure shows an embodiment in which each material layer 1 has an insulating material on both sides of the layer. In the figure, the insulating material is varnish, in particular self-adhesive varnish. This corresponds to a preferred embodiment.

[0099] Preferably, the insulation material and the material layer are bonded together.

[0100] The material layer 1 has varnish 2 with an insulation thickness d2 on an upper layer side and varnish 3 with an insulation thickness d3 on a lower layer side.

[0101] It is also possible for material layer 1 to comprise a different type of insulation material and additional varnish. It is also possible for material layer 1 to comprise a different type of insulation material on one side of the layer and varnish on the other side. It is also possible for material layer 1 to comprise a mixture of a different type of insulation material and varnish.

[0102] The figure also shows a centrally arranged material recess 5 (for later connection to a shaft, see FIG 5 ). A rotation axis R passes through a center point of the material recess 5.

[0103] The described reference symbols are also valid for the following figures, provided they are present in the embodiments, and are not explained again for reasons of clarity.

[0104] FIG 3 shows material layer 1 in a side view.

[0105] The figure shows the thinnest version of material layer 1, since only one layer of solid particles forms material layer 1. The solid particles in the figure are granular material. In other words: The solid particles are small spheres that lie next to each other and are preferably FIG 1 described sintering, are connected to each other.

[0106] In the figure, the layer thickness d corresponds to the diameter of a solid particle.

[0107] Likewise, the figure shows only one layer of insulation material 2 on the upper layer side and only one layer of insulation material 3 on the lower layer side. The insulation thickness d2 and the insulation thickness d3 in the figure correspond to the diameter of a solid ceramic particle or a solid lacquer particle.

[0108] However, two or more solid particles can also be stacked on top of each other to form material layer 1. Two or more ceramic solid particles can also be stacked on top of each other to form the insulation. Two or more lacquer solid particles can also be stacked on top of each other to form the insulation.

[0109] FIG 4 shows a method for producing a material layer structure for a rotor of a dynamoelectric rotary machine.

[0110] In a method step S10, a first material layer is additively manufactured, wherein the first material layer comprises at least one material layer.

[0111] In a process step S11, an insulating material is applied to the first material layer. The insulating material is preferably lacquer, in particular self-adhesive varnish. However, the insulating material can also be ceramic or another material.

[0112] In a method step S12, at least one further material layer is additively manufactured, wherein the at least one further material layer comprises at least one material layer.

[0113] In a method step S13, an insulating material is applied to the at least one further material layer.

[0114] In a method step S14, the first and at least one further material layer are joined together.

[0115] In process step S15, the material layers are bonded together. If bonding varnish was applied to the material layers in process steps S11 or S13, the material layers are bonded together by baking.

[0116] In this case, bonding means that the material layers are bonded together, preferably using pressure and heat. Pressure and heat cause the bonding varnish to soften, bond the material layers together, and then harden. This has the advantage over other joining methods such as welding, punching, and riveting in that the material layers do not have contact points that could damage the material. Furthermore, magnetic flux is not disrupted, and no material stresses or deformations occur.

[0117] The method shown is also suitable for a stator of a dynamoelectric rotary machine.

[0118] FIG 5 shows a rotor 11 of the dynamoelectric rotary machine.

[0119] The rotor 11 has a material layer structure 9. In the figure, the material layer structure comprises a plurality of material layers 1 arranged one above the other along the rotation axis. The material layer structure 9 is connected to a shaft 7.

[0120] In the figure, material layer 1 is consolidated with at least one additional material layer. The figure shows a plurality of material layers 1 consolidated together.

[0121] Bonding is particularly successful with self-bonding varnish, as it can be easily applied. Subsequent bonding of the material layers 1 creates a stable and robust bond.

[0122] FIG 6 shows a side view of the dynamoelectric rotary machine 15.

[0123] The machine 15 has the rotor 11, which comprises the shaft 7 and the material layer structure 9. The rotor 11 can rotate in a stator 12 along the rotation axis R.

Claims

1. Method for producing a material layer (1) for a rotor (11) or a stator (12) of a dynamoelectric rotary machine with a layer thickness (d) between 0.5 and 500 µm with the following steps: - applying a suspension, having at least one binding agent and solid particles, through a template onto a base area in order to obtain a green body, - driving the binding agent out of the green body, in particular by means of debindering, - creating a permanent cohesion of the solid particles by heating and / or by means of compaction, in particular by means of sintering.

2. Method according to claim 1, wherein an insulation material (2, 3) is applied to the material layer (1) on at least one layer side.

3. Method according to one of the preceding claims, wherein an insulation material (2, 3) is applied to the material layer on both layer sides.

4. Method according to one of the preceding claims, wherein a varnish, in particular thermosetting varnish, is applied to the material layer (1).

5. Method according to one of the preceding claims, wherein the solid particles comprise particles of electrically and / or magnetically conductive material, in particular metal particles.

6. Method according to one of the preceding claims, wherein the solid particles comprise particles from soft-magnetic material.

7. Method according to one of the preceding claims, wherein the suspension is pseudoplastic.

8. Material layer (1) for a rotor (11) or a stator (12) of a dynamoelectric machine (15), produced according to one of claims 1 to 7, - wherein the material layer (1) has a layer thickness (d) between 0.5 and 500 µm, in particular between 10 and 100 µm, - wherein the material layer (1) has a soft-magnetic material, - wherein the material layer (1) has an insulation material (2, 3) on at least one layer side.

9. Material layer (1) according to claim 8, wherein the material layer (1) has an insulation material (2, 3) on both layer sides.

10. Material layer (1) according to one of claims 8 or 9, wherein the material layer (1) has varnish, in particular thermosetting varnish.

11. Material layer (1) according to one of claims 8 to 10, wherein the material layer (1) can be strengthened with at least one further material layer (1).

12. Material layer (1) according to one of claims 8 to 11, wherein the material layer (1) has a material cut-out (5) arranged substantially centrally.

13. Method for producing a material layer structure (9) for a rotor (11) of a dynamoelectric rotary machine (15) with the following steps: - additive manufacturing of a first material layer (1) according to one of claims 8 to 12, wherein the first material layer (1) comprises at least one material slice, - applying an insulation material (2, 3) to the first material layer (1), - additive manufacturing of at least one further material layer (1), wherein the at least one further material layer (1) comprises at least one material slice, - applying an insulation material (2, 3) to the at least one further material layer (1), - joining the first and the at least one further material layer (1), - reciprocally strengthening the material layers (1).

14. Method according to claim 13, wherein a material layer structure (9) is produced by means of a plurality of material layers (1) with a layer thickness (d) of 0.5 to 500 µm.

15. Material layer structure (9) for a rotor (11) of a dynamoelectric rotary machine (15), wherein the material layer structure (9) has a plurality of material layers (1) arranged one above the other according to one of claims 8 to 12.