Device for manufacturing a slotted tube for an electric machine

Abstract

Device (1) for manufacturing a slotted tube (2) for an electric machine, in particular an electric machine of a motor vehicle, which device (1) has two tool halves (3, 4) that can be moved relative to each other into an open state and a closed state, which in the closed state define a cavity (7) of the device (1) in which a core (5) can be received or is received, on which at least one structural layer (6), in particular comprising a fiber material, is arranged, wherein the cavity (7) and / or the core (5) have a basic shape that deviates from a circular shape, in particular a cross-sectional shape.

Description

[0001] The invention relates to a device for producing a can for an electrical machine, in particular an electrical machine of a motor vehicle, which device has two tool halves which can be moved relative to one another into an open state and a closed state and which, in the closed state, delimit a cavity of the device in which a core can be received or is received, on which at least one structural layer, in particular comprising a fiber material, is arranged.

[0002] Devices for producing cans for electrical machines are generally known from the prior art. A structural layer, for example a so-called "liner" comprising multiple layers of fiber material, is arranged on a core, for example a metal cylinder. The fiber material arranged on the core is inserted together with the core into the cavity, for example a lower mold half, so that the device can then be closed. The can is typically formed by evacuating and injecting a matrix material into the cavity, which matrix material can then be solidified, in particular by tempering.

[0003] After the matrix material has solidified, the produced can, together with the core, can be inserted into the base body opening of a stator base body of an electrical machine. The process for inserting the can is complex due to the tight tolerances between the outer surface of the can and the inner surface of the base body opening. Specifically, the stator base body is heated before inserting the can, and the can and the core on which the can is arranged are cooled in a defined manner. When inserting the can, for example, when it is fully in contact with the inner surface of the base body opening, comparatively high joining forces are required to overcome the friction between the outer surface of the can and the inner surface of the base body opening.In particular, the joining process must be strictly monitored to prevent damage to the can during joining to the stator base body, particularly the formation of microcracks on the outer surface of the can. This requires not only the effort required for the targeted temperature control of the core, can, and stator base body, but also the high joining forces, as well as additional time expenditure.

[0004] The invention is based on the object of providing an improved device for producing a can for an electrical machine, in which the assembly of the can in the stator base body is improved.

[0005] The object is achieved by a device having the features of claim 1. Advantageous embodiments are the subject of the subclaims.

[0006] As described, the invention relates to a device for producing a can for an electrical machine, in particular an electrical machine for a motor vehicle. The electrical machine can be designed as a drive device of the motor vehicle, for example as a traction drive, in order to output a torque for driving the motor vehicle. For example, the electrical machine can be part of a drive train, for example designed as an electric axle drive. The device has two tool halves that are movable relative to one another. The tool halves can thus be moved between an open state and a closed state. In particular, an upper tool half can be moved in the vertical direction relative to a stationary lower tool half in order to open and close the device.The tool halves delimit a cavity, in particular in the closed state, in which the previously described core is received, for example an elongated body, in particular made of metal, on which the at least one structural layer is provided, for example rolled or wound.

[0007] The invention is based on the finding that the cavity and / or the core have a basic shape, in particular a cross-sectional shape, that deviates from a circular shape. By providing the basic shape of the cavity and / or the core, which deviates from the circular shape typically used in the production of cans, an improvement in assembly is achieved when inserting the finished can into the base body opening of the stator base body. Since the base body opening of the stator base body is still circular in terms of its cross-section, this means that the basic shape of the can, which deviates from the circular shape, is initially not fully in contact with the inner surface of the base body opening during insertion of the can into the stator base body.

[0008] This reduces the joining force required, thus preventing potential damage to the can. This means that the joining process, in which the can is inserted into the stator base body, can be carried out more quickly. The can, which also deviates from the circular shape due to the shape of the cavity and / or the core, adapts to the shape of the base body opening as it is inserted into the base body opening. Once the insertion of the can is complete, i.e. the can has been completely or almost completely inserted into the base body opening, the basic shape of the can corresponds to the basic shape of the base body opening, whereby the can can lie fully against the inner surface of the base body opening. In other words, the can changes its basic shape as the can is inserted into the base body opening.

[0009] According to one embodiment of the device, it can be provided that the cavity and / or the core have a, in particular curved, polygonal or oval basic shape. A polygonal basic shape is generally understood to be a basic shape with multiple corners, for example triangular, hexagonal, octagonal or polygonal. An oval basic shape particularly refers to a round shape that deviates from a circular shape, for example an ellipse. This ensures that when the finished can is inserted into the base body opening, there is no flat, but rather a linear contact between the outer surface of the can and the inner surface of the base body opening. In particular, the initial point or line contact changes into flat contact as the can is increasingly inserted, whereby upon completion of assembly, the can is mounted in the base body opening with its entire surface in contact.

[0010] A curved polygonal shape is understood in particular to be a shape in which the basic shape has corners, but the connecting lines between the corners are not straight lines, but curved lines. Consequently, the core and / or the cavity form curved inner surfaces or outer surfaces, respectively, with their center of curvature lying in the region of the longitudinal axis or axis of symmetry of the cavity or core. An example of such a curved polygonal basic shape is the so-called "Reuleaux triangle," which can form the cross-sectional shape of a curved triangular basic shape. The curvature of the lines connecting the vertices or the side surfaces connecting the edges can be transferred accordingly to more than three corners.

[0011] The described device can further be developed such that the cavity and / or core are triangular, hexagonal, or octagonal. Here, the basic shape refers specifically to the cross-sectional shape, meaning that the cross sections of the cavity and / or core have a triangular, hexagonal, or octagonal shape. As previously described, these basic shapes can, in particular, be curved, i.e., the lines connecting the corners or the surfaces connecting the edges are curved, in particular convex.

[0012] According to a further embodiment of the device, it can be provided that a diameter of the structural layer and / or of the manufactured can on the core is larger than an inner diameter of a base body opening of a stator base body. The diameter of the basic shape that deviates from the circular shape of the base body opening is understood in particular to be the maximum distance between the longitudinal axis of the core or the cavity and the respective corner or edge. In other words, the (outer) diameter of the structural layer and / or of the manufactured can on the core is understood to be the maximum distance between the longitudinal axis of the can or the structural layer and one of the corner points in the case of a polygonal basic shape or the longer axis of the oval basic shape.

[0013] This (maximum) diameter of the structural layer and / or the manufactured can is larger than the inner diameter of the base body opening of the stator base body, which, as described, is the same size everywhere with a circular base body opening. Therefore, when the manufactured can is inserted into the base body opening, point or line contact occurs at the outer diameters of the can where it is larger than the inner diameter of the base body opening. The deviating shape is adapted to the basic shape of the base body opening as it is inserted, so that full-surface contact is formed between the can and the base body opening after insertion is complete.To simplify the insertion of the can into the base body opening, a funnel device can be used whose diameter, for example, changes conically. The diameter of the funnel device is larger than the diameter of the stator base body and, accordingly, also larger than the inner diameter of the base body opening. As described, the funnel device can taper, for example, conically, so that a larger opening faces the can and the smaller opening faces the base body opening, thus allowing for improved insertion of the can.

[0014] According to a further development of the device, it can be provided that the at least one structural layer provided on the core is applied to the core, in particular to a surface of the core, by rolling and / or winding. In principle, the at least one structural layer can be applied to the core in any desired manner. Furthermore, a combination of different structural layers is possible, which differ, for example, in a material parameter, for example, with regard to the fiber material, in particular from GRP, textile, ceramic, natural or glass fibers, or any combinations thereof.

[0015] Furthermore, the device can be further developed such that the at least one structural layer has at least one carrier layer and at least one reinforcement layer different from the carrier layer. The structural layer can be designed, for example, as a “hybrid liner”. The reinforcement layer can in particular be arranged on the carrier layer in such a way that the finished can is designed to be flexible, in particular locally, in order to improve assembly. Due to the flexible design, the can is sufficiently flexible during insertion, so that a change in the basic shape during insertion is easier. With the at least one reinforcement layer, the mechanical behavior of the manufactured can can be influenced such that it is sufficiently stable to absorb loads during operation of the electrical machine, for example coolant pressure.Furthermore, the can can be sufficiently resistant to damage during deformation when inserted into the base body opening.

[0016] According to a further embodiment of the device, the core can have a deformation device designed to change the basic shape of the core. For example, the core can be hollow. In particular, the deformation device, which can change the basic shape of the core, can be provided in the interior of the core. For example, a first basic shape can be assumed during production of the can, during which the core is arranged in the cavity. If the core is introduced into the base body opening together with the can, the deformation device can suitably change the basic shape of the core, for example to support the application of the can to the inner surface of the base body opening. The deformation device can, for example, have at least one bellows that can be inflated in the interior of the core to deform the core.Mechanical elements can also be provided that mechanically shift or deform the outer surfaces of the core.

[0017] In addition to the previously described device for producing a can, the invention relates to a device for producing an assembly for an electrical machine, in particular an electrical machine of a motor vehicle, which device is designed to introduce a can, in particular arranged on a core, with a basic shape deviating from a circular shape, in particular produced by means of a previously described device, into a base body opening of a stator base body for an electrical machine, in particular by means of a funnel device. The device for producing the can and the device for producing an assembly can be integrated into a common system. In particular, the can is first produced on the core, as described.Subsequently, the device for manufacturing the assembly for the electrical machine is used to insert the can arranged on the core into the stator base body. For this purpose, a funnel device can be used, in particular, to simplify the insertion of the can into the base body opening. The funnel device can therefore be used as an insertion aid. Since at least one diameter of the can is larger than the inner diameter of the base body opening, the funnel device can thus enable or support a transition from the larger outer diameter to the inner diameter.

[0018] The invention further relates to a method for producing a can for an electrical machine, in particular an electrical machine of a motor vehicle, wherein, in a closed state of a device, a cavity is delimited by two tool halves of the device, in which cavity a core is received, on which at least one structural layer, in particular comprising a fiber material, is arranged, wherein the cavity and / or the core have a basic shape, in particular a cross-sectional shape, that deviates from a circular shape. The invention also relates to a method for producing an assembly for an electrical machine, wherein a can is introduced into a base body opening of a stator base body of the electrical machine, wherein the can has a basic shape, in particular a cross-sectional shape, that deviates from a circular shape.

[0019] The described methods can in particular be carried out on the devices described above. In particular, a method for producing the can can be carried out first, as described, wherein the produced can can then be used in the method for producing the assembly and can be introduced into the base body opening of the stator base body. As described, the can changes its basic shape when it is inserted into the base body opening or during the insertion process, so that at the end of the assembly process the can lies flat against the inner surface of the base body opening. The method for producing the assembly can in particular be carried out on the device for producing the assembly. Both methods can be carried out on a system that comprises the two devices.

[0020] All advantages, details, and features described with regard to the device for producing the split tube are fully transferable to the device for producing the assembly, the method for producing the split tube, and the method for producing the assembly. Within the scope of this description, all advantages, details, and features of the devices and methods are interchangeable, transferable, and combinable.

[0021] The invention is explained below using exemplary embodiments with reference to the figures. The figures are schematic representations and show: Fig. 1a-1c show a schematic diagram of a device for producing a can for an electrical machine in different process states; Fig. 2 a manufactured split tube according to an embodiment; Fig. 3a-3d each show a can according to different embodiments; Fig. 4a-4d show a section of a device for producing an assembly for an electrical machine in different process states in a perspective view; and Fig. 5a-5d show a section of a device for producing an assembly for an electrical machine in different process states in cross-sectional view.

[0022] Fig. 1a-1c show a device 1 for producing a can 2 for an electrical machine (not shown in detail), specifically an electrical machine of a motor vehicle. The electrical machine can be designed, in particular, as a drive device for the motor vehicle. The device 1 has two tool halves 3, 4, which can also be referred to as the upper tool part and the lower tool part, or as the upper tool half 3 and the lower tool half 4. Fig. 1a shows an opening state of the device 1, in which the device 1 is open, i.e., the tool halves 3, 4 are moved apart by relative movement, in particular in the vertical direction. In this case, a core 5 can be provided, on which at least one structural layer 6, for example comprising a fiber material, in particular GRP, ceramic, textile, natural, glass fibers or any other desired fiber type, is provided. The structural layer 6 is applied to the core 5, for example, by laying, winding, or rolling. The structural layer 6 can have various sub-regions, in particular a carrier layer, which can, for example, be continuous in the axial direction. At least one reinforcement layer can be provided on the at least one carrier layer, so that the mechanical properties of the structural layer 6 and thus of the finished can 2 can be adjusted as desired.The carrier layer and the reinforcement layer can differ in at least one material and / or manufacturing parameter.

[0023] As in Fig. As shown in Figure 1b, the core 5 can be introduced together with the structural layer 6 into a cavity 7 defined by the mold halves 3, 4. The device 1 is then brought into the closed state by moving the mold halves 3, 4 toward each other, thus closing the cavity 7. Fig. Figure 1c shows the closed state of the device 1, in which the cavity 7 is closed. In this state, the cavity 7 can, for example, be evacuated and a matrix material injected. As can be seen from Fig. As can be seen in Figures 1a-1c, both the basic shape of the cavity 7 and the basic shape of the core 5 and the structural layer 6 deviate from a circular shape. Purely by way of example, the core 5, the structural layer 6, and the cavity 7 have a curved polygonal shape, for example, a curved triangular shape. After the matrix material has hardened, for example, by tempering the core 5 and / or the cavity 7, the at least one structural layer 6 impregnated with the matrix material, which matrix material has hardened, forms the can 2 on the core 5.

[0024] The finished can 2, which is still arranged on the core 5, is for example in Fig. 2. The finished can 2 can be used, for example, in a device 8 for producing an assembly 13 for an electrical machine, which is described below with reference to Fig. 4, Fig. 5. The structural layer 6, the core 5 and the cavity 7, and thus also the can 2, can have any other oval or polygonal, in particular curved polygonal, basic shapes.

[0025] In the Fig. 3a-3d show an exemplary selection of different possible basic shapes. Fig. Figure 3a shows a curved polygonal, namely a curved triangular shape. It is evident that vertices 9 are connected by curved lines 10. Translated from the cross-sectional shape into the three-dimensional form, this means that the edges 11 of the basic shape are connected by curved surfaces 12 (cf. Fig. 2). Fig. 3b shows a curved hexagonal shape purely as an example, where any other number of corners 9, for example eight or twelve, or even odd numbers of corners 9, for example five, seven or eleven, are possible. Fig. 3c shows a triangular oval shape and in Fig. In 3d, a purely oval shape, for example an ellipse, is shown.

[0026] In Fig. 4a-4d show various process states of the device 8 for producing the assembly 13 for the electrical machine. Accordingly, Fig. 5a-5d show cross-sectional views of the respective process states. The assembly 13 comprises a stator base body 14, which can also be referred to as a "lamination stack." The stator base body 14 has a base body opening 15 into which the can 2 is to be inserted in order to separate a rotor space from a stator space of the electric machine in the assembled state.

[0027] In Fig. 4a, Fig. 5a shows a state in which the can 2 is present on the core 5 outside the base body opening 15 of the stator base body 14, wherein the can 2 has its shape from the manufacturing process in the device 1, purely by way of example curved triangular, wherein any other shape, for example according to Fig. 3a-3d is also possible. In this state, optional tempering of core 5, can 2, and stator base body 14 can be performed. For this purpose, the stator base body 14 is heated, and the core 5 and can 2 are cooled. The targeted tempering is used to reduce the dimensions of the can 2 and the core 5 and simultaneously increase the inner diameter of the base body opening 15, so that joining is improved. As can be seen in particular from Fig. 5a, an outer diameter 16 of the split tube 2, measured from a longitudinal center axis of the split tube 2 to the corner 9 of the split tube 2, is larger than an inner diameter 17 of the circular base body opening 15. This ensures in particular that during insertion, for example shown in Fig. 5b, Fig. 5c initially a point contact ( Fig. 5a) of the corners 9 on an inner surface of the base body opening 15, which is then converted into a line contact ( Fig. 5b, Fig. 5c) and then into a surface contact ( Fig. 5d).

[0028] In Fig. 4b, Fig. 5b shows that the can 2, in particular using a funnel device 18, which has, for example, a first opening facing away from the stator base body 14, the inner diameter of which is larger than that of a second opening facing the base body opening 15. This improves the assembly of the can 2 in the base body opening 15. Subsequently, as for example in Fig. 4c, Fig. 5c, the split tube 2 is inserted into the base body opening 15, with the outer surface of the split tube 2 adhering to the inner surface of the base body opening 15 as it is inserted, and the split tube 2 thus assumes the basic shape of the base body opening 15. For this purpose, a deformation device can be provided in the core 5, which can be hollow, for example, with which the outer surface of the core 5 can be deformed in order to assist the deformation of the split tube 2 during insertion into the base body opening 15.

[0029] Fig. 4d, Fig.5d shows, by way of example, the manufactured assembly 13 in which the can 2 is mounted in the base body opening 15. The core 5 can then be removed, so that the can 2 arranged on the stator base body 14 delimits a radially inner rotor chamber from a radially outer stator chamber. The dashed line shows how the basic shape of the can 2 has changed from the initial state in which the can 2 left the device 1. It is clear that the basic shape deviating from the circular shape requires significantly less joining force, since the can 2, which may in particular be oversized, does not lie flat over the entire inner surface of the base body opening 15. Instead, the can 2 adapts to the geometry of the stator base body 14 during insertion and, in the final state, lies flat against the inner surface of the stator base body 14.

[0030] The advantages, details, and features shown in the individual exemplary embodiments can be combined, interchanged, and transferred to one another as desired. As already described, device 1 and device 8 can be combined in a common system. The methods described herein for producing the can 2 and for producing the assembly 13 can be carried out on device 1 and device 8, respectively. All advantages, details, and features described with regard to the individual devices 1, 8 and the individual methods can also be fully combined, interchanged, and transferred to one another. Reference symbol 1 device 2 split tube 3, 4 tool half 5 core 6 structural layer 7 Cavity 8 Device 9 Corner 10 Line 11 edge 12 Area 13 Assembly 14 Stator base body 15 Main body opening 16 outer diameter 17 inner diameter 18 Funnel device

Claims

[1] Device (1) for producing a can (2) for an electrical machine, in particular an electrical machine of a motor vehicle, which device (1) has two tool halves (3, 4) which are movable relative to one another into an open state and a closed state and which, in the closed state, delimit a cavity (7) of the device (1), in which a core (5) can be received or is received, on which at least one structural layer (6), in particular comprising a fiber material, is arranged, characterized by that the cavity (7) and / or the core (5) have a basic shape, in particular a cross-sectional shape, that deviates from a circular shape. [2] Device (1) according to claim 1, characterized by that the cavity (7) and / or the core (5) have a, in particular curved, polygonal or oval basic shape. [3] Device (1) according to claim 1 or 2, characterized bythat the cavity (7) and / or the core (5) are triangular or hexagonal or octagonal. [4] Device (1) according to one of the preceding claims, characterized by that a diameter of the structural layer (6) and / or of the manufactured gap tube (2) on the core (5) is larger than an inner diameter (17) of a base body opening (15) of a stator base body (14). [5] Device (1) according to one of the preceding claims, characterized by that the at least one structural layer (6) provided on the core (5) is applied to the core (5), in particular to a surface of the core (5), by means of rolling and / or winding. [6] Device (1) according to one of the preceding claims, characterized by that the at least one structural layer (6) has at least one carrier layer and at least one reinforcement layer different from the carrier layer. [7] Device (1) according to one of the preceding claims, characterized by that the core (5) has a deformation device which is designed to change the basic shape of the core (5). [8] Device (8) for producing an assembly (13) for an electrical machine, in particular an electrical machine of a motor vehicle, which device (1) is designed to introduce a can (2), in particular arranged on a core (5), with a basic shape deviating from a circular shape, in particular produced by means of a device (1) according to one of the preceding claims, into a base body opening (15) of a stator base body (14) for an electrical machine, in particular by means of a funnel device (18). [9] Method for producing a can (2) for an electrical machine, in particular an electrical machine of a motor vehicle, wherein in a closed state of a device (1) a cavity (7) is delimited by two tool halves of the device (1), in which a core (5) is received, on which at least one structural layer (6), in particular comprising a fiber material, is arranged, characterized by that the cavity (7) and / or the core (5) have a basic shape, in particular a cross-sectional shape, that deviates from a circular shape. [10] Method for producing an assembly (13) for an electrical machine, wherein a can (2) is introduced into a base body opening (15) of a stator base body (14) of the electrical machine, characterized by that the split tube (2) has a basic shape, in particular a cross-sectional shape, that deviates from a circular shape.

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