Process for manufacturing a can for an electric machine

Abstract

A process for manufacturing a can (1) for an electric machine, in particular an electric machine of a motor vehicle, said can (1) being placeable or placed in a main part opening (2) in a stator main part (3) of the electric machine, wherein when the can (1) is mounted in the main part opening, it is designed to separate a stator chamber (10) from a rotor chamber (10) of the electric machine, wherein at least one base layer (4), in particular a woven or non-woven, having a plurality of structural elements (6) is provided, the at least one base layer (4) is placed on a core (5), and at least one reinforcement layer (7), which differs from the at least one base layer (4), is placed against or on at least one area of the at least one base layer (4) in at least one reinforcement region of the at least one base layer (4) and, together with the at least one base layer (4), is imbibed with a matrix material (8) and hardened.

Description

[0001] Method for producing a can for an electrical machine

[0002] The invention relates to a method for producing a can for an electrical machine, in particular an electrical machine of a motor vehicle, which can be arranged or is arranged in a base body opening of a stator base body of the electrical machine, wherein the can is designed in a state mounted in the base body opening to separate a stator space and a rotor space of the electrical machine, wherein at least one base layer having a plurality of structural elements, in particular a scrim or a woven fabric, is provided, wherein the at least one base layer is arranged on a core.

[0003] The use of cans in electrical machines to separate the stator chamber and the rotor chamber, as well as methods for producing such cans, are generally known from the prior art. Typically, a monolithic base layer, for example a scrim or woven fabric of a fiber material, in particular glass fibers, is wound onto a core and impregnated with a matrix material, for example a resin, and then cured. The can can then be inserted into the base body opening of a stator base body, thus separating the stator chamber from the rotor chamber, so that, for example, different cooling circuits are not mixed with one another during operation of the electrical machine.

[0004] It is also known from the prior art that different electrical machines or similar electrical machines in different areas of application are subject to different boundary conditions. Depending on the boundary conditions, for example desired power ranges and the like, different requirements are placed on the can. For example, it is known that for electrical machines that are to be operated under high-performance requirements, higher demands must be placed on the can in order to realize operation in a high-performance range. Purely as an example, for such high-performance operation, a higher coolant pressure is realized within the electrical machine compared to normal operation, which coolant pressure the can must withstand. Such higher requirements can be met, for example, by selecting the material for the structural elements of the base layer.

[0005] However, it is known that fiber materials for the structural elements of the base layer are more complex and expensive for high-performance applications than lower-performance materials. For example, the use of glass fibers or natural fibers for the base layer is less complex and therefore cheaper than, for example, ceramic fibers and carbon fibers. Since the different fiber materials have different properties, for example with regard to their stiffness and the like, a compromise is often necessary when selecting the material for the structural elements. For example, it is important to ensure that the can reliably guarantees the tightness between the rotor chamber and the stator chamber, while also providing sufficient structural integrity to withstand the coolant pressure, for example within the stator chamber.

[0006] This can lead to the entire base layer being unnecessarily made of higher-quality materials for the production of cans for electrical machines, regardless of their specific application, or to different cans, i.e. in particular different base layers, having to be used for electrical machines of the same construction, which are, however, intended for different areas of application, which entails process-related disadvantages.

[0007] The invention is based on the object of specifying a method for producing a can for an electrical machine which is improved compared to the prior art and in which the can can be produced in a modular manner.

[0008] As described at the outset, the invention relates to a method for producing a can for an electrical machine, for example an electrical machine of a motor vehicle. To produce the electrical machine, the can is introduced into or arranged in a base body opening of a stator base body of the electrical machine. In the assembled state, in which the can is arranged in the base body opening, the can separates the stator space of the electrical machine from a rotor space of the electrical machine. The can is produced by providing a base layer which has a plurality of structural elements, in particular a scrim or a woven fabric. The base layer is arranged on a core, for example a metal cylinder, for example wound or rolled up.

[0009] The invention is based on the finding that, in at least one reinforcement region of the at least one base layer, at least one reinforcement layer different from the at least one base layer is arranged on or on at least one surface of the at least one base layer and is impregnated with a matrix material and cured together with the at least one base layer. The invention thus proposes, instead of forming the base layer from different materials depending on a specific application or for different applications of the same electrical machine, providing a reinforcement layer on the base layer that is different from the base layer, if required.

[0010] This allows the properties of the base layer to be locally reinforced. For example, pressure resistance can be increased in selected reinforcement areas of the can by arranging the reinforcement layer there on the base layer. Since the surfaces or reinforcement areas where a reinforcement layer is to be arranged on the base layer can be selected arbitrarily, a modular design of the can is possible. In other words, depending on the intended use or area of ​​application, the base layer, which can be selected the same for all or similar electrical machines, can optionally be reinforced with at least one reinforcement layer.For example, for a high-performance application, the can can be expanded by at least one reinforcement layer, thus reinforcing the base layer, which, for example, is sufficient for an application with lower requirements to seal the stator chamber from the rotor chamber, so that, for example, higher coolant pressures can be achieved in the electrical machine. In this case, the at least one reinforcement layer is arranged on the base layer, for example, placed on a surface of the base layer, or the base layer is placed on the reinforcement layer. The reinforcement layer and the base layer are impregnated together with a matrix material and cured together, so that the can can be produced.

[0011] According to a further development of the method, it can be provided that the at least one reinforcement layer has second structural elements that are different from the first structural elements arranged in the at least one base layer, wherein the first structural elements differ from the second structural elements in at least one fiber parameter, in particular in a mechanical parameter. As described above, the reinforcement layer can be designed differently from the at least one base layer. This allows fundamentally different materials to be used for the base layer and the reinforcement layer compared to monolithic construction variants known from the prior art. In particular, higher-quality materials can be used for the reinforcement layer, which would be too complex or too expensive for forming the entire base layer.In other words, reinforcement layers can be applied locally to the base layer where necessary, allowing the can to be reinforced there. For example, if high-performance applications lead to increased requirements in different areas of the can, these requirements can be met specifically by the reinforcement layer, without the need for the entire base layer to be manufactured monolithically from a high-performance material.

[0012] According to one embodiment of the method, the second structural elements, i.e. the structural elements of the at least one reinforcement layer, can have a higher rigidity and / or a higher modulus of elasticity than the first structural elements, i.e. the structural elements of the base layer. As a result, comparatively simpler or more cost-effective structural elements, for example glass fibers, can be used for the base layer, which fundamentally ensure the tightness of the can. In addition, structural elements with a higher rigidity or higher modulus of elasticity can be used in the at least one reinforcement layer in order to specifically stiffen the can, for example to make the can resistant to higher coolant pressures in the stator chamber. The second structural elements in the at least one reinforcement layer can therefore also be referred to or considered as “reinforcing fibers.”

[0013] Furthermore, the method can provide for the second structural elements to have a defined electrical conductivity in at least one reinforcement region, in particular to have an electrically insulating effect. Through targeted selection of the structural elements, for example as carbon fibers or ceramic fibers, a required electrical conductivity can be ensured in different regions of the can. For example, the can can be reinforced in the region of the winding heads by at least one reinforcement region or at least one reinforcement layer, whereby no electrical conductivity is desired in this region, so that electrically insulating second structural elements or reinforcement fibers, for example ceramic fibers, can be used there.

[0014] Due to the separate formation or provision of the at least one base layer and the at least one reinforcement layer, any fiber parameters in the base layer and the reinforcement layer can in principle be selected to be different from one another. For example, the base layer can have structural elements with different fiber densities and / or fiber angles and / or fiber thicknesses than the reinforcement layer (or vice versa). For example, the first structural elements in the at least one base layer can have a first fiber density and / or a first fiber angle and / or a first fiber thickness, and the second structural elements in the at least one reinforcement layer can, in contrast, have a second fiber density and / or a second fiber angle and / or a second fiber thickness.In different base layers and / or in different reinforcement layers, the first structural elements and / or the second structural elements can be designed to be similar to one another or also different.

[0015] In principle, it is possible within the scope of the method described herein to combine different base layers with different reinforcement layers as desired, whereby in the simplest case, exactly one base layer and exactly one reinforcement layer can be arranged next to one another. Likewise, any number of different reinforcement layers can be arranged on exactly one base layer, or vice versa. For example, the method can provide for the at least one base layer to be arranged radially inside the at least one reinforcement layer, or for the at least one base layer to be arranged radially outside the at least one reinforcement layer, or for the at least one base layer to be arranged radially between two reinforcement layers, or for the at least one reinforcement layer to be arranged radially between two base layers.

[0016] The radial direction described herein refers to the rotational axis of the electrical machine or the longitudinal axis, in particular the longitudinal center axis, of the can. As described, the individual layers, i.e., at least one base layer and the at least one reinforcement layer, can be applied to a core, for example, wound, rolled, or drawn on, or combinations thereof.

[0017] According to a further development of the method, it can be provided that the at least one base layer comprises structural elements that have glass fibers and / or natural fibers and / or textile fibers and / or that the at least one reinforcing layer comprises structural elements that have carbon fibers and / or ceramic fibers. As described above, this makes it possible to form the at least one base layer from cost-effective and inexpensive fibers, so that the base layer can basically ensure the tightness of the can. The reinforcing layer, which is attached to the at least one base layer in order to reinforce the at least one base layer, can, in contrast, comprise reinforcing fibers that can also be referred to as "high-performance fibers." These can be designed, for example, as carbon fibers and / or ceramic fibers.

[0018] Furthermore, the method can provide for the structural elements of the at least one reinforcement layer to be arranged in a defined three-dimensional arrangement, in particular in a net-like or grid-like manner, in the reinforcement layer. The described embodiment makes it possible for the structural elements in the reinforcement layer not to have to be provided over the entire surface, as for example within the base layer, but rather for the reinforcement layer to have a defined three-dimensional arrangement of structural elements. The reinforcement layer can thus also be designed as a "framework structure" that forms a three-dimensional net or grid. The three-dimensional arrangement of the structural elements can be generated, for example, based on simulation. The three-dimensional arrangement within the reinforcement layer can be locally different, i.e.that the at least one reinforcement layer has at least two sub-regions which have different three-dimensional arrangements of the structural elements.

[0019] As already described, more than one reinforcement layer can be provided for producing the can. According to one embodiment of the method, it can be provided that at least two reinforcement layers separated in the axial direction are arranged on the at least one base layer. For example, selected regions of the base layer, in particular at axial end regions of the can, can be locally reinforced by reinforcement layers. Likewise, a defined distance between the reinforcement layers in the axial direction can be determined, in which distance reinforcement layers are formed on the at least one base layer. The different reinforcement layers adjacent in the axial direction can be of the same type and / or different types, for example, have different extensions in the axial direction or have structural elements made of different materials.In particular, at least two similar reinforcement layers can be combined with at least one different reinforcement layer.

[0020] In addition to the method, the invention relates to an assembly for an electrical machine, in particular an electrical machine of a motor vehicle, which assembly comprises a can that can be arranged or is arranged in a base body opening of a stator base body of the electrical machine, wherein the can, when mounted in the base body opening, is designed to separate a stator chamber and a rotor chamber of the electrical machine, wherein the can has at least one base layer having a plurality of structural elements, in particular a scrim or a woven fabric, wherein in at least one reinforcement region of the at least one base layer, at least one reinforcement layer different from the at least one base layer is arranged on the at least one base layer and is impregnated with a matrix material and cured together with the at least one base layer.

[0021] The invention further relates to an electrical machine having a previously described assembly. The invention further relates to a motor vehicle having a previously described electrical machine and / or a previously described assembly. All advantages, details, and features described with reference to the method are fully applicable to the assembly, the electrical machine, and the motor vehicle. The assembly can, in particular, be manufactured using a previously described method, so that all advantages, details, and features are realized there.

[0022] The invention is explained below using exemplary embodiments with reference to the figures. The figures are schematic representations and show:

[0023] Fig. 1 shows a state in a method for producing a can for an electrical machine;

[0024] Fig. 2 shows a detail of an axial sectional view of an electrical machine with a can according to a first embodiment;

[0025] Fig. 3 shows a detail of an axial sectional view of an electrical machine with a can according to a second embodiment;

[0026] Fig. 4 shows a section of an axial sectional view of an electrical machine with a can according to a third embodiment; and

[0027] Fig. 5 shows a section of an axial sectional view of an electrical machine with a can according to a fourth exemplary embodiment. Fig. 1 shows a state in a method for producing a can 1 for an electrical machine (not shown in detail). As is known, the can 1, after completion, is inserted into a base body opening of a stator base body 3 of the electrical machine in order to delimit the rotor space 9 from the stator space 10. Figs. 2-5 each show a section of a cross-sectional view of an assembled can 1 in different exemplary embodiments in a base body opening 2 of a stator base body 3.

[0028] Fig. 1 further shows that the can 1 has a base layer 4, which is, for example, rolled or wound onto a core 5. The base layer 4 has first structural elements 6, for example glass fibers. Fig. 1 also shows that, on a surface of the base layer 4, two reinforcement layers 7 are arranged, by way of example only, which are spaced apart in the axial direction and have second structural elements 8, for example carbon fibers or ceramic fibers. The two reinforcement layers 7 are arranged, by way of example, at axial end regions of the base layer 4 and the can 1, respectively. The number, positioning, and design of the individual reinforcement layers 7 can be changed as desired. It is also possible to arrange only a single reinforcement layer 7 or more than two reinforcement layers 7 on the base layer 4.In order to complete the can 1, the base layer 4 and the reinforcement layers 7 can be impregnated together with a matrix material and cured.

[0029] As can be seen from Fig. 1, the second structural elements 8 in the reinforcement layers 7 are arranged in a defined three-dimensional arrangement, in particular in a grid-like manner. This distinguishes the reinforcement layers 7, for example, from the full-surface design of the first structural elements 6 in the base layer 4. The specific design of the reinforcement layer 7 can be selected as desired and can, for example, also have second structural elements 8 arranged over the full surface. As described, the reinforcement layers 7 can also be designed differently from one another. By providing at least one reinforcement layer 7, the base layer 4 can be locally reinforced, such that it is not necessary to form the entire base layer 4 from high-performance fibers.Instead, the base layer 4 can be formed from simpler fibers, for example glass fibers, natural fibers or textile fibers, and only in axial areas or reinforcement areas where this is necessary, the base layer 4 can be reinforced by reinforcement layers 7, for example made of carbon fibers or ceramic fibers.

[0030] 2-5 show sections of a cross-sectional view through an electrical machine which can have the can 1. Of course, the view is cut out so that the view continues endlessly in the circumferential direction, forming a closed can 1. The can 1 clearly separates the radially inner rotor chamber 9 from the stator chamber 10 which is radially outer with respect to the can 1. In Fig. 2 it is shown, for example, analogous to Fig. 1, that the at least one reinforcement layer 7 is arranged radially outward on the at least one base layer 4, ie that the base layer 4 is arranged radially inward with respect to the at least one reinforcement layer 7.

[0031] Fig. 3 shows a representation which is inverted with respect to Fig. 2, in which the at least one reinforcement layer 7 is arranged radially inward relative to the base layer 4, i.e. the base layer 4 is arranged radially outward relative to the reinforcement layer 7. Fig. 4 shows a variant of the can 1, in which a base layer 4 is arranged between two reinforcement layers 7, i.e. in each case one reinforcement layer 7 is arranged radially inward of the base layer 4 and at least one reinforcement layer 7 is arranged radially outside of the base layer 4. Fig. 5 shows a representation which is inverted with respect to Fig. 4, in which a reinforcement layer 7 is arranged between two base layers 4, i.e. in which one base layer 4 is arranged radially inward and one base layer 4 is arranged radially outward relative to the at least one reinforcement layer 7.The advantages, details, and features shown in the individual exemplary embodiments can be combined with one another as desired, are interchangeable, and are transferable to one another. In particular, in each of the embodiments shown in Figs. 2-5, any number of reinforcement layers 7 can be implemented spaced apart in the axial direction. The electric machine or the assembly comprising the can 1 can be part of a motor vehicle, so the described details can also be transferred to the electric machine, the assembly, and the motor vehicle.

[0032] Reference symbol

[0033] 1 split tube

[0034] 2 main body opening

[0035] 3 Stator base body

[0036] 4 Base layer

[0037] 5 core

[0038] 6 first structural element

[0039] 7 Reinforcement layer

[0040] 8 second structural element

[0041] 9 Rotor chamber

[0042] 10 Stator chamber

Claims

Patent claims 1. A method for producing a can (1) for an electrical machine, in particular an electrical machine of a motor vehicle, which can be arranged or is arranged in a base body opening (2) of a stator base body (3) of the electrical machine, wherein the can (1) is designed, in a state mounted in the base body opening (2), to separate a stator chamber (10) and a rotor chamber (10) of the electrical machine, wherein at least one base layer (4) having a plurality of structural elements (6), in particular a scrim or a woven fabric, is provided, wherein the at least one base layer (4) is arranged on a core (5), characterized in thatthat in at least one reinforcement region of the at least one base layer (4), at least one reinforcement layer (7) different from the at least one base layer (4) is arranged on or on at least one surface of the at least one base layer (4) and is impregnated with a matrix material and cured together with the at least one base layer (4).

2. Method according to claim 1, characterized in that the at least one reinforcement layer (7) has second structural elements (8) which are different from first structural elements (6) arranged in the at least one base layer (4), wherein the first structural elements (6) differ from the second structural elements (8) in at least one fiber parameter, in particular in a mechanical parameter.

3. Method according to claim 2, characterized in that the second structural elements (8) have a higher rigidity and / or a higher modulus of elasticity than the first structural elements (6).

4. Method according to claim 2 or 3, characterized in that the second structural elements (8) have a defined electrical conductivity in at least one reinforcement region, in particular have an electrically insulating effect.

5. Method according to one of claims 2 to 4, characterized in that the first structural elements (6) in the at least one base layer (4) and the second structural elements (8) in the at least one reinforcement layer (7) have different fiber densities and / or fiber angles and / or fiber thicknesses.

6. Method according to one of the preceding claims, characterized in that the at least one base layer (4) is arranged radially inside the at least one reinforcement layer (7) or that the at least one base layer (4) is arranged radially outside the at least one reinforcement layer (7) or that the at least one base layer (4) is arranged radially between two reinforcement layers (7) or that the at least one reinforcement layer (7) is arranged radially between two base layers (4).

7. Method according to one of the preceding claims, characterized in that the at least one base layer (4) comprises structural elements (6) which have glass fibers and / or natural fibers and / or textile fibers and / or that the at least one reinforcement layer (7) comprises structural elements (8) which have carbon fibers and / or ceramic fibers.

8. Method according to one of the preceding claims, characterized in that the structural elements (6) of the at least one reinforcement layer (7) are arranged in a defined three-dimensional arrangement, in particular in a net-like or grid-like manner, in the reinforcement layer (7).

9. Method according to one of the preceding claims, characterized in that at least two reinforcement layers (7) separated in the axial direction are arranged on the at least one base layer (4).

10. Assembly for an electrical machine, in particular an electrical machine of a motor vehicle, which assembly comprises a can (1) which is arranged in a base body opening (2) of a stator base body (3) of the electrical machine can be arranged or is arranged, wherein the can (1) is designed, in a state mounted in the base body opening (2), to separate a stator space (10) and a rotor space (10) of the electrical machine, wherein the can (1) has at least one base layer (4) having a plurality of structural elements (6), in particular a scrim or a woven fabric, characterized in that in at least one reinforcement region of the at least one base layer (4), at least one reinforcement layer (7) different from the at least one base layer (4) is arranged on the at least one base layer (4) and is impregnated with a matrix material and cured together with the at least one base layer (4). 11 . Electrical machine comprising an assembly according to the preceding claim.

12. Motor vehicle comprising an electric machine according to the preceding claim and / or an assembly according to claim 10.

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