COMPONENT FOR AN ELECTRIC MACHINE WITH A POLYMER COATING, AND METHOD FOR COATING A COMPONENT

Abstract

A component for an electric machine includes a flat region in which an electric line runs when the component is integrated into the electric machine and which includes a sharp edged structure. A polymer layer adheres to the flat region without further aid such as to mask the sharp-edged structure and thereby protect from damage the electric line on the flat region. The polymer layer is made of cured plastic adhesive and jetted onto the flat region in the form of threads, such that the threads are spin-coated on top of one another in the form of overlapping loops and form a network structure which spans the sharp-edged structure.

Claims

1.-3. (canceled)

14. A component for an electric machine, comprising: a flat region in which an electric line runs when the component is integrated into the electric machine and which includes a sharp-edged structure; and a polymer layer adhering to the flat region without further aid such as to mask the sharp-edged structure and thereby protect from damage the electric line on the flat region, said polymer layer being made of cured plastic adhesive and jetted onto the flat region in the form of threads, such that the threads are spin-coated on top of one another in the form of overlapping loops and form a network structure which spans the sharp-edged structure.

15. The component of claim 14, wherein the component is embodied as a stator including a winding overhang on a connection side, said flat region being arranged on an end winding of the winding overhang, with a section of the electric line lying on the flat region and fixed to the winding overhang by the polymer layer.

16. The component of claim 15, wherein the polymer layer covers the section of the electric line.

17. The component of claim 15, wherein the plastic adhesive is jetted in the form of threads onto the flat region containing the section of the electric line lying thereon, such that the threads are spin-coated on top of one another hi the form of overlapping loops and form a network structure.

18. The component of claim 14, wherein the component is embodied as a stator or a rotor or a housing.

19. The component of claim 14, wherein the plastic adhesive is a thermoplastic hot melt adhesive.

20. The component of claim 19, wherein the thermoplastic hot melt adhesive is a polyolefin or a polyamide.

21. An electric machine, comprising a component, said component comprising a flat region in which an electric line runs when the component is integrated into the electric machine and which includes a sharp-edged structure, and a polymer layer adhering to the flat region without further aid such as to mask the sharp-edged structure and thereby protect from damage the electric line on the at least one flat region, said polymer Dyer being made of cured plastic adhesive and jetted onto the flat region in the form of threads, such that the threads are spin-coated on top of one another in the form of overlapping loops and form a network structure which spans the sharp-edged structure.

22. The electric machine of claim 21, wherein the component is embodied as a stator including a winding overhang on a connection side, said flat region being arranged on an end winding of the winding overhang, with a section of the electric line lying on the flat region and fixed to the winding overhang by the polymer layer.

23. The electric machine of claim 22, wherein the polymer layer covers the section of the electric line.

24. The electric machine of claim 22, wherein the plastic adhesive is jetted in the form of threads onto the flat region containing the section of the electric line lying thereon, such that the threads are spin-coated on top of one another in the form of overlapping loops and form a network structure.

25. The electric machine of claim 21, wherein the component is embodied as a stator or a rotor or a housing.

26. The electric machine of claim 21, wherein the plastic adhesive is a thermoplastic hot melt adhesive, in particular a polyolefin or a polyamide.

27. The electric machine of claim 21, wherein the component is embodied as a housing and the flat region is embodied as a region of the housing with an aperture, and further comprising an electric line runs through the aperture, wherein the polymer layer including the cured plastic adhesive spans and seals the aperture and adheres both to the electric line and to the housing.

28. A method for creating a polymer layer adhering to a flat region of a component of an electric machine, with an electric line running on the flat region when the component is integrated into the electric machine and the flat region including a sharp-edged structure, said method comprising: creating with a nozzle a thread of a thermoplastic hot melt adhesive; and while the thread is created, moving the nozzle in such a way that the thread is applied onto the flat region in layers and covering the whole area so that the thread is spin-coated in the form of overlapping loops, in order to form a network structure, with the network structure spanning the sharp-edged structure in order to protect from damage the electric line on the flat region.

29. The method of claim 28, wherein the thread is applied in the form of slings.

30. The method of claim 28, wherein the thermoplastic hot melt adhesive is fed to the nozzle at an operating pressure of between 1 bar and 10 bar.

31. The method of claim 28, wherein the thermoplastic hot melt adhesive is fed to the nozzle at an operating temperature of between 180° C. and 220° C.

32. The method of claim 28, wherein the thermoplastic hot melt adhesive is applied fully automatically.

33. The method of claim 28, wherein the thermoplastic hot melt adhesive is applied fully automatically using a robot.

Description

[0038] Further features, properties and advantages of the present invention emerge from the following description with reference to the accompanying figures, in which, shown schematically:

[0039] FIG. 1 shows a component integrated into an electric machine;

[0040] FIG. 2 shows a rotary electric machine;

[0041] FIG. 3 shows a section through the laminated core of the rotary electric machine in FIG. 2;

[0042] FIG. 4 shows a connection-side winding overhang of the rotary electric machine in FIG. 2;

[0043] FIG. 5 shows an enlarged view of FIG. 4;

[0044] FIG. 6 shows a stator assembled into a housing;

[0045] FIG. 7 shows an enlarged view of FIG. 6;

[0046] FIG. 8 shows a sectional view of a housing in the region of the terminal box;

[0047] FIG. 9, 10 show threads of the thermoplastic hot melt adhesive when being applied to a flat region to create the polymer layer, and

[0048] FIG. 11 shows fully automatic application of the plastic adhesive.

[0049] In the exemplary embodiments and figures identical or identically acting elements can each be provided with identical reference characters.

[0050] FIG. 1 schematically shows a component 1 that is integrated into an electric machine 5. The component 1 can comprise multiple polymer layers 2a, 2b adhering to corresponding flat regions 3a, 3b of the component 1. The polymer layers 2a, 2b comprise cured plastic adhesive. At least when the component 1 (as shown in FIG. 1) is integrated into the electric machine 5 at least one electric line can run 4a, 4b on the respective flat regions. FIG. 1 shows a form of embodiment in which an electric line is provided for each region.

[0051] It can be seen in FIG. 1 that the flat regions 3a, 3b are completely covered by the corresponding polymer layers 2a, 2b.

[0052] The electric lines (for example 4b) can for example be fastened to the corresponding region (for example 3b) partially beneath the polymer layer (for example 2b) and by this polymer layer that adheres to the component 1.

[0053] The flat regions (for example 3a) can have an edge 6. Component 1 may be provided with such edges 6 for reasons related to production. The edges 6 can be so sharp that they pose a hazard for the electric lines 4a running at these edges 6, if they touch the edges 6 during insertion/feeding-in or due to vibrations during operation of the electric machine 5 and for example damage the insulation thereof.

[0054] The polymer layer can for example be non-porous.

[0055] The electric lines 4a, 4b can for example be connection lines power lines or sensor signal lines.

[0056] The polymer layers 2a, 2b can for example consist of the cured plastic adhesive. For example, thermoplastic hot melt adhesive, for example polyolefin or polyamide, can be used. Specifically, good results have been achieved with the materials 3M Scotch Weld 3731, 3789 and 3779 from the company 3M, wherein the first material mentioned is a polyolefin and both the other materials are polyamides.

[0057] The polymer layers 2a, 2b can also comprise RT-curing (RT=room temperature, approximately 25° C.) cured adhesives or be formed from these. The plastic adhesive used can include a thread reinforcement. The polymer layers 2a, 2b can be formed by spraying the plastic adhesive on and for example take the form of a spray-on wallpaper. The plastic adhesive can be chemically curing, so for example duromer plastics can be used, which for example are UV-curing. Physically curing plastics can be used as plastic adhesive. Filled plastics (threads, particles) can be used as plastic adhesive, provided they can still be applied, for example in the form of a spray-on wallpaper. Solvent-based plastics can also be used as plastic adhesive, which solidify by evaporation of the solvent (for example hairspray, PVA), Reactive resins (for example epoxy, PEI, PU) can be used as plastic adhesive.

[0058] The component can be embodied as a stator of an electric machine, for example a rotary electric machine.

[0059] FIG. 2 shows by way of example a rotary electric machine 50 which has a stator 10. The electric machine can in individual cases be embodied as a linear electric machine. The rotary electric machine 50 can also have a rotor 11 in addition to the stator 10. In the case of a rotary electric machine the rotor 11 is rotatably arranged on a rotor shaft 12, which in turn is rotatably mounted in bearings 13. As a result the rotor shaft 12 and the rotor 11 can be rotated about an axis of rotation 14. Other components of the electric machine 50 that are normally present, such as for example bearing shields, are not illustrated in FIG. 1.

[0060] The stator 10 has a laminated core 15 with a plurality of individual stator laminations 16. Only a few of the stator laminations 16 are provided with their reference character in PG 1, in order not to unnecessarily overload FIG. 1. The laminated core 15 is manufactured in the conventional manner and hence need not be explained in greater detail.

[0061] FIG. 3 shows a section through the laminated core 15. It can in particular be seen in FIG. 3 that slots 17 are made in the laminated core 15. The slots 17 can—as is standard practice—be made in the laminated core 15 by the stator laminations already being correspondingly punched out. The aforementioned edges 18, which can be particularly sharp, can arise during the punching-out process. Only some of these sharp edges of the slots 17 are provided with their reference character in FIG. 3.

[0062] Windings 19 of a stator winding system are inserted into the slots 17. The windings 19 can form a multiphase stator winding system, for example a three-phase stator winding system. The windings 19 of the individual phases are generally inserted into the slots 17 sequentially one after the other. The insertion of the windings 19 as such takes place in the conventional manner and hence need not be explained in greater detail. The windings 19 can if required be embodied as what are known as wild windings or laid windings.

[0063] In this case regions of the edges 18 which come into contact with the windings 19, or may do so, can be provided with a polymer layer adhering to these regions and comprising a cured plastic adhesive, such that direct contact between the windings 19 and the edges 18 is prevented, as a result of which the windings 19 are protected from damage.

[0064] FIG. 4 shows one of the two winding overhangs of the electric machine 50—namely the connection-side winding overhang 20. It is expedient if the connection-side winding overhang 20 of the electric machine 50 is located where a terminal board is provided in the housing 23 (see FIG. 6) of the electric machine 50.

[0065] In accordance with FIG. 4 the windings 19 can have winding ends in the region of the connection-side winding overhang 20, which can form electric lines (here: connection lines) 21 for a three-phase system, for example. Supply voltages, for example the supply voltages U, V, W of a three-phase system, can be applied to the electric lines 21 during operation of the electric machine 50.

[0066] It can be seen from FIG. 4 that the electric lines 21 (round wires, enameled wires) can for example be positioned radially onto the end winding of the connection-side winding overhang 20 and fixed there. The lines 21 can be fastened respectively with a corresponding polymer layer 2u, 2v, 2w to the corresponding region of the end winding of the connection-side winding overhang 20. In this case the polymer layer 2u, 2v, 2w can cover a section of the respective line 21 like a wallpaper and fix this thereto by adhesion to the end winding of the winding overhang 20.

[0067] The polymer layers 2u, 2v, 2w can consist of the cured plastic adhesive. In this case the plastic adhesive can be jetted in the form of threads onto the flat region of the end winding of the winding overhang 20 containing the section lying thereon of the at least one electric line 21, such that the threads are spin-coated on top of one another in the form of overlapping loops and form a network structure. The threads can have a diameter of approximately 50-500 μm.

[0068] The electric lines 21 may have only one insulating coating in the form of an insulating enamel. The insulating coating is not illustrated in the figures. This insulating coating could be very easily damaged when the lines 21 are handled, if the lines 11 are handled as they are. For reasons of electrical voltage safety and operating safety it may be expedient to sheathe the lines 21 with an insulator 22 as per the illustration in FIG. 6 and to fasten the One 21 sheathed with an insulator 22 to the end winding of the connection-side winding overhang 20 using the polymer layer 2u, 2v, 2w. The insulator 22 can include a thermoplastic hot melt adhesive or consist thereof.

[0069] The electric lines 21 may be sheathed over only part of their length (for example starting at the winding overhang 20 and ending shortly before the end of the respective line 21). The connection of the corresponding supply voltage U, V. W to the non-sheathed end of the respective electric line 21 can take place subsequently in a terminal box 24 (FIG. 6) of the electric machine 50,

[0070] FIG. 6 shows the stator 10 assembled into a housing 23. For simplicity, only two electric lines 21 are shown in FIG. 6, which are fastened to the end winding layers adhering to the end winding. The electric lines 21 are routed into the terminal box 24 of the housing 23, in order to be connected there via a terminal board. In a three-phase system six connection lines, three phases with two ends each, can be fastened to the end winding of the winding overhang.

[0071] FIG. 7 shows an enlarged view of FIG. 6, which—in addition to the edges 18 described above—illustrates a further example in which the flat region has a sharp-edged structure. Specifically it is apparent from FIG. 7 that the structure can be embodied as an aperture edge 25 of the aperture of the terminal box 24. In particular it is apparent from FIG. 7 that at least one region of the aperture edge 25, which could come into contact with the Ones 21, is masked by a polymer layer 2 adhering to the housing material, in ogler to protect the electric lines 21 against damage.

[0072] The polymer layer can likewise consist of the cured plastic adhesive, which is jetted in the form of threads onto the region of the aperture edge 25, such that the threads are spin-coated on top of one another in the form of overlapping loops and form a network structure which spans at least the region of the aperture edge 25.

[0073] FIG. 8 shows a sectional view of the housing 23 in the region of the terminal box 24. It is apparent from FIG. 8 that the flat region can include an aperture, for example an aperture in the terminal box 24 leading to the interior of the housing 23, The electric lines 21 can be fed through the aperture into the terminal box 24, wherein the aperture containing electric lines 21 laid through the aperture can be sealed by means of a polymer layer 2′ that includes the cured plastic adhesive. In particular, the plastic can (for example in a form-fit manner) seal the aperture, which can be embodied as a cable leadthrough, in order to protect the interior of the electric machine 50 from moisture or dirt.

[0074] The polymer layer 2′ can include the same materials as the aforementioned polymer layers 2a, 2b, 2u, 2v, 2w, 2 or can consist of the same materials. Such polymer layers can have a thickness of approximately 0.1 mm to 3 mm, preferably between 0.5 mm and 1.5 mm, for example approximately 1.0 mm.

[0075] It has been shown to be particularly advantageous to use thermoplastic hot melt adhesive as the material for forming the polymer layers, in particular the polymer layer 2′ sealing the cable leadthrough.

[0076] With reference to FIG. 9, an example is shown of a method for creating a polymer layer adhering to at least one flat region of a component of an electric machine. Thermoplastic hot melt adhesive is used in the method. At least the aforementioned polymer layers 2a, 2b, 2u, 2v, 2w, 2, 2′ can be created using the method described below.

[0077] Specifically, FIG. 9 shows an example of creating the polymer layer 2″ for sealing the cable leadthrough in the terminal box 24 of the housing 23. Naturally the method can also be used to create edge protection—if the flat region includes a sharp-edged structure—and/or to fasten electric lines 21 to a flat region, for example to the connection-side winding overhang 20.

[0078] In this case a thread 31 of a thermoplastic hot melt adhesive can be created by means of a nozzle 30. During the creation the nozzle 30 is moved such that because of the travel of the nozzle 30 the thread 31 is applied onto the flat region in layers and covering the whole area. In this case all three spatial degrees of freedom R are preferably exploited. The thread 31 can have a diameter for example in a range between 50 μm and 500 μm.

[0079] In one form of embodiment the thread 31 can be applied to the flat region in the form of slings 32. Particularly if the flat region includes the cable leadthrough, in other words an aperture, the application in the form of slings 32 is advantageous, because the hot melt adhesive spans the aperture much like a net.

[0080] Although FIG. 9 shows that one of the electric lines 21 runs through the slings 32 or through the 3D helix that is formed by the thread 31, the thread 31 can be spin-coated in any manner in order to seal the hollow spaces between the lines 21 and the cable leadthrough, as shown in FIG. 8.

[0081] FIG. 10 shows how part of the cable leadthrough can be sealed, as well as a polymer layer 2′ which on the one hand adheres to one of the electric lines 21 and on the other hand to the housing 23 and seals part of the cable leadthrough.

[0082] It is expedient if the thermoplastic hot melt adhesive is fed to the nozzle 30 at an operating pressure of between 1 bar and 10 bar, and/or at an operating temperature of between 180° C. and 220° C.

[0083] In a specific experiment an adhesive based on a polyolefin with a melting temperature of approximately 200° C. was used for example. The adhesive was jetted on at an operating temperature T of 220° C. and a pressure p of 3 bar. The adhesive exited the nozzle 30 at a velocity of approximately 5 m/s. The distance of the nozzle 14 from the respective flat region was approximately 8 cm, the speed of rotation of the nozzle 30 was 600 rpm. The slings 32 adhered very well to each of the aforementioned materials. In the case of the cable leadthrough the slings 32 resulted in the hollow spaces to be sealed being completely spanned.

[0084] The application of the thermoplastic hot melt adhesive can take place fully automatically.

[0085] For example, in accordance with the illustration in FIG. 11 a corresponding manufacturing facility can have a robot 33, by means of when the jetting-on takes place. Depending on the way in which the component 1, 10 is fixed in a retaining device 34 of the manufacturing facility it is possible for the flat regions 3a, 3b to each be situated at defined locations. In addition it is conceivable for the manufacturing facility to have an optical detection system 35, by means of which the location and the course of the flat region to be sprayed can be detected prior to the thermoplastic hot melt adhesive being jetted. The optical detection system 35 can for example be embodied as a 3D camera. In the case of an optical detection the detected location and the detected course of the flat regions can be fed to a control device 36. The control device 36 is thereby accordingly able to take into account the detected location and the detected course of the flat regions 3a, 3b to be sprayed during the travel of the nozzle 30.

[0086] Although the invention has been illustrated and described in greater detail by preferred exemplary embodiments, the invention is not restricted by the disclosed examples. Variations can be derived therefrom by the person skilled in the art, without departing from the scope of protection of the invention, as is defined by the following claims.