Rotor for an axial flow machine, rotor, and method for producing the rotor

Abstract

The invention relates to a rotor (RO) for an axial flow machine of an at least partially electrically driven motor vehicle, comprising an annular flange (FL) having an outer collar (KR), a bracing device (VE) which is spaced from the outer collar (KR) in the radial direction of the flange (FL) and is frictionally and / or form-fittingly connected to the flange (FL), a plurality of magnets (MA) which are fixed between the outer collar (KR) and the bracing device (VE) by means of the bracing device (VE), and a flux ring (RR) which is situated between the plurality of magnets (MA) and the flange (FL) and is formed in the circumferential direction of the flange (FL) by a plurality of flux-ring segments (RRS), and the flux-ring segments (RRS) rest, in relation to a radial direction of the flange (FL), at least in part and / or in portions against a collar inner face which is directed inwards in the radial direction of the flange (FL).

Description

[0001] Description

[0002] Rotor for an axial flow machine, rotor and method for producing the rotor

[0003] The invention relates to a rotor for an axial flux machine with a multi-part return ring. The invention also relates to an axial flux machine with the rotor according to the invention. A further subject of the invention is a method for producing the rotor according to the invention.

[0004] Rotors for axial flux machines are generally known. One such rotor is described, for example, in DE 10 2022 202 959 A1. The rotor has a flange with a continuous annular yoke. A plurality of magnets are arranged on the yoke, which are clamped to the flange via a clamping device and thus fixed to the flange. The continuous annular yoke made of ferromagnetic material results in no or only a reduced magnetic return flux in the area of ​​the outer circumference of the magnets, which can reduce the performance of the axial flux machine.

[0005] It is an object of the invention to provide a rotor for an axial flow machine with which the performance of the axial flow machine can be increased.

[0006] This problem is solved by the subject matter of the independent patent claims. Preferred developments of the invention are the subject matter of the dependent patent claims, the following description, and / or the drawings. Each disclosed feature can represent an aspect of the invention, both individually and in combination, unless explicitly stated otherwise in the description.

[0007] In a first aspect, the invention relates to a rotor for an axial flux machine of an at least partially electrically driven motor vehicle, comprising a circular ring-shaped flange with an outer collar, a clamping device arranged at a distance from the outer collar in the radial direction of the flange and connected to the flange in a force-locking and / or form-locking manner, a plurality of magnets which are fixed between the outer collar and the clamping device via the clamping device, and a return ring arranged between the plurality of magnets and the flange, which return ring is formed from a plurality of return ring segments in the circumferential direction of the flange, and the return ring segments, with respect to a radial direction of the flange, at least partially and / or in sections abut against an inner side of the collar which is directed inwards in the radial direction of the flange.

[0008] In other words, according to the first aspect of the invention, a rotor for an axial flux machine is provided. The axial flux machine is preferably a component of an at least partially electrically powered motor vehicle and is designed and / or configured to drive the motor vehicle. The rotor has a circular ring-shaped flange. The flange comprises an outer collar, which preferably extends in the axial direction of the circular ring-shaped flange. At a distance from the outer collar, relative to a radial direction of the flange, a clamping device is non-positively and / or positively connected to the flange. A plurality of magnets are clamped between the outer collar and the clamping device via the clamping device and are thus fixed to the flange. A return ring, which can also be referred to as a "back iron", is arranged between the magnets and the flange.The return ring is designed and constructed to form the return path of the magnetic flux between adjacent magnets within the rotor. In this way, the magnetic flux within the rotor and consequently also the motor torque can be increased, which can have a beneficial effect on the performance of the axial flux machine. In the circumferential direction of the flange, the return ring is formed from a plurality of return ring segments. The return ring segments bear at least partially and / or in sections against a collar inner side directed inwards in the radial direction of the flange. This is preferably possible by displacing the return ring elements arranged on the flange in a radial direction of the flange.Thus, the return ring segments are essentially shifted outwards as far as possible and can thus also enable a return flow of the magnets in the radially outer area of ​​the flange, which can increase the performance of the axial flux machine.

[0009] The return ring segments are preferably made of a ferromagnetic material. The ferromagnetic material can preferably be, but is not limited to, a soft magnetic composite material, also referred to as a "soft magnetic composite (SMC)." In soft magnetic composite materials, individual metal powder particles are preferably coated with an insulating layer, ensuring that the return ring segment consists of countless, individually insulating iron particles and thus has reduced electrical conductivity. This can reduce eddy current losses, which can have a beneficial effect on the performance of the axial flux machine.

[0010] An advantageous development of the invention lies in the fact that an intermediate element made of or with a ferritic or martensitic structure is arranged between two return ring segments arranged adjacent to one another in the circumferential direction of the flange. In this way, if a distance or gap exists between two return ring segments, this gap can be closed by the intermediate element, so that a continuous magnetic return flux in the circumferential direction of the rotor or flange can be enabled via the return ring. Consequently, the magnetic flux within the rotor can be increased in this way, which can have a beneficial effect on the motor torque. An increased motor torque can have a beneficial effect on the performance of the axial flux machine. Furthermore, the return ring segments can be securely fixed in their position on the flange via the intermediate elements.

[0011] In this context, a preferred embodiment of the invention is that the intermediate element has a T-shaped configuration with respect to a radial direction of the rotor. The upright web of the T-shaped intermediate element runs in the radial direction of the rotor. The free end of the upright web of the T-shaped intermediate element points inwards in the radial direction of the rotor. The crossbar ends of the T-shaped intermediate element preferably engage in corresponding recesses in the return ring segments. Thus, when the intermediate element is fixed to the flange, the crossbar of the T-shaped intermediate element acts as a stop for the return ring segment resting against the intermediate element in the radial direction of the rotor.Due to the recess in the return ring elements, these can be displaced further outwards in the radial direction of the rotor, which can have a beneficial effect on the magnetic return flux and thus on the performance of the axial flux machine. A preferred embodiment of the invention is that the intermediate element is connected to the flange in a form-fitting and / or force-fitting manner. The form-fitting and / or force-fitting connection is preferably a screw connection. For this purpose, it is provided that a fastening opening is formed in an end region of a free end of the upright web of the T-shaped intermediate element, which is directed inwards in the radial direction of the rotor. The fastening opening is preferably a closed-edge bore that completely penetrates the intermediate element.A fastening element, such as a screw or rivet, can preferably be passed through the mounting opening and connected to the flange. This allows the intermediate element to be securely and captively fixed to the flange.

[0012] On the one hand, the return ring segments can be fixed to the flange via the intermediate elements in a form-fitting and / or force-fitting manner.

[0013] An advantageous embodiment of the invention provides that the majority of the return ring segments are arranged on the flange in a materially bonded manner, at least in sections. In other words, it can be provided that an adhesive layer is preferably applied to the flange and / or the return ring segments, and the return ring segments are fixed or fastened to the flange in a materially bonded manner via the adhesive layer. This can have a beneficial effect on the structural rigidity of the rotor. Increased structural rigidity of the rotor leads to a reduction in torsion of the rotor as a result of a magnetic field relative to a stator arranged at a distance from an air gap. Due to the reduced torsion, the air gap between the stator and rotor can be reduced, which can have a beneficial effect on the performance of the axial flux machine.

[0014] According to a preferred embodiment of the invention, the plurality of magnets is arranged, at least in sections, in a materially bonded manner on the return ring segments. In other words, it can be provided that an adhesive layer is preferably applied to the magnets and / or the return ring segments, and the magnets are fixed or fastened to the return ring segments in a materially bonded manner via the adhesive layer. This can have a beneficial effect on the structural rigidity of the rotor. Increased structural rigidity of the rotor reduces twisting of the rotor as a result of a magnetic field relative to a stator arranged at a distance from an air gap. Due to the reduced twisting, the air gap between the stator and rotor can be reduced, which can have a beneficial effect on the performance of the axial flux machine.

[0015] An advantageous development of the invention is that the outer collar is designed as a projection in the axial direction of the flange with a rear locking lug directed inward in the radial direction. In other words, the outer collar has a distal end in the axial direction of the flange. Starting from the distal end, the outer collar has an undercut, so that a rear locking lug directed inward in the radial direction of the flange is formed. The rear locking lug allows the magnet to engage in the undercut and thus be fixed to the flange in a form-fitting and / or force-fitting manner, on the one hand via the rear locking lug and on the other hand via the clamping device. In addition, the rear locking lug allows the magnets to be arranged largely on the outside in a radial position of the rotor, which is advantageous for the torque and thus the performance of the axial flux machine.

[0016] It is conceivable that the outer collar is connected to the flange in a material-to-material, form-fitting and / or force-fitting manner. A preferred development of the invention is that the outer collar is formed integrally with the flange. This allows the manufacturing steps and manufacturing costs of the flange to be reduced. In addition, the outer collar can have increased structural rigidity due to its integral design with the flange. Increased structural rigidity of the rotor reduces torsion of the rotor as a result of a magnetic field relative to a stator arranged at a distance from an air gap. Due to the reduced torsion, the air gap between stator and rotor can be reduced, which can have a beneficial effect on the performance of the axial flux machine.

[0017] In an advantageous development of the invention, it is provided that the outer collar is formed continuously in the circumferential direction of the flange.

[0018] Continuous design means that the outer collar is uninterrupted in the circumferential direction of the flange. A continuous outer collar can have increased structural rigidity. The increased structural rigidity of the rotor can, as explained several times above, have a beneficial effect on the performance of the axial flux machine. An alternative development of the invention is that the outer collar has at least one interruption relative to the circumferential direction of the flange. The outer collar can thus have at least one interruption in the circumferential direction of the flange, preferably a plurality of spaced-apart interruptions. The one interruption or the multiple interruptions can reduce the weight of the rotor, taking into account the required rigidity of the outer collar.A reduced weight of the rotor can have a beneficial effect on the overall weight of the axial flux machine.

[0019] It is conceivable that the clamping device is constructed as a single piece. This could be advantageous for the manufacturing process and also reduce manufacturing costs.

[0020] An advantageous embodiment of the invention is that the clamping device is designed in several parts. It is conceivable that the number of clamping devices is equal to the number of magnets. This allows the magnet to be individually attached to the flange. This allows for manufacturing-related tolerances of the magnets to be taken into account when attaching the magnets to the flange.

[0021] In a second aspect, the invention relates to an axial flow machine with the inventive.

[0022] The rotor is preferably arranged at an axial distance from a stator. An air gap is formed between the rotor and the stator. The axial flux machine can therefore also be referred to as an axial gap machine.

[0023] In a third aspect, the invention relates to a method for producing the rotor according to the invention, comprising the steps:

[0024] - Providing a flange with an outer collar;

[0025] - Arranging return ring segments on the flange, whereby the return ring segments are first displaced in the axial direction of the flange and are displaced at the level of the collar in the radial direction of the flange towards the outer collar;

[0026] - Arranging the plurality of magnets on the return ring segments; - Fastening at least one clamping device on the flange, whereby the magnets are positively fixed on the flange via the at least one clamping device and the outer collar.

[0027] In other words, according to the third aspect of the invention, a method for manufacturing the rotor is provided.

[0028] In a first step, the annular flange is provided, which has an outer collar.

[0029] In a second step, the magnetic return ring segments are placed on the flange. The magnetic return ring segments are initially displaced in the axial direction of the flange and, at the level of the collar, are then displaced in the radial direction of the flange toward the outer collar. This allows the magnetic return ring segments to be placed further outward in the radial direction of the flange, which can have a beneficial effect on the magnetic return flux and torque, which in turn is beneficial for the performance of the axial flux machine.

[0030] In a third step, the magnets are arranged on the return ring segments.

[0031] In a fourth step, the magnets are pressed onto the return ring segments by means of a clamping device, which is particularly preferably designed in several parts, and are fixed in a form-fitting manner on the flange by means of the at least one clamping device and the outer collar.

[0032] Preferably, after the second step and before the third step, an intermediate element is inserted between two adjacent return ring segments. In this way, if a distance or gap exists between two return ring segments, this gap can be closed by the intermediate element, so that a continuous magnetic return flux in the circumferential direction of the rotor or flange can be enabled via the return ring. Consequently, the magnetic flux within the rotor can be increased in this way, which can have a beneficial effect on the torque. An increased torque can have a beneficial effect on the performance of the axial flux machine. Furthermore, the return ring segments can be securely fixed in their position on the flange using the intermediate elements.

[0033] Furthermore, it is preferably provided that an adhesive layer is applied to the flange and / or the return ring segments before the first step and after the second step. The return ring segments can be fixed or fastened to the flange via the adhesive layer. This can have a beneficial effect on the structural rigidity of the rotor. Increased structural rigidity of the rotor leads to a reduction in torsion of the rotor as a result of a magnetic field relative to a stator arranged at a distance from an air gap. Due to the reduced torsion, the air gap between the stator and rotor can be reduced, which can have a beneficial effect on the performance of the axial flux machine.

[0034] Advantageously, an adhesive layer is applied to the magnets and / or the return ring segments after the second step and before the third step. The adhesive layer allows the magnets to be firmly fixed or secured to the return ring segments. This can have a beneficial effect on the structural rigidity of the rotor. Increased structural rigidity of the rotor reduces torsion of the rotor as a result of a magnetic field relative to a stator arranged at an air gap. Due to the reduced torsion, the air gap between the stator and rotor can be reduced, which can have a beneficial effect on the performance of the axial flux machine.

[0035] It should be noted that all features described above and below with respect to one aspect of the present invention equally apply to any other aspect of the present invention. In particular, all features of the rotor can equally apply to the axial flux machine and / or the method for manufacturing the rotor. This also applies vice versa.

[0036] Further features and advantages of the present invention emerge from the dependent claims and the following exemplary embodiments. The exemplary embodiments are not restrictive, but rather to be understood as examples. They are intended to enable the skilled person to implement the invention. The applicant reserves the right to make individual and / or several of the features disclosed in the exemplary embodiments the subject of patent claims or to incorporate such features into existing patent claims. The exemplary embodiments are explained in more detail with reference to drawings.

[0037] In these show:

[0038] Fig. 1 is an exploded view of the rotor,

[0039] Fig. 2 to 6 steps for manufacturing the rotor, the rotor being shown in longitudinal section, Fig. 7 a plan view of the rotor.

[0040] Figure 1 shows an exploded view of a rotor RO. The rotor RO has a circular flange FL. The flange FL comprises an outer collar KR, which preferably extends in the axial direction of the circular flange FL. The flange FL has an inner side IS aligned in the axial direction of the flange FL.

[0041] An adhesive layer AS is applied to the inner side IS of the flange FL. A plurality of return ring segments RRS are arranged circumferentially relative to one another on the adhesive layer AS, forming a return ring RR. The return ring segments RRS are made of a ferromagnetic material. The ferromagnetic material can preferably be, but is not limited to, a soft magnetic composite material, also referred to as a "soft magnetic composite (SMC)". In soft magnetic composite materials, individual metal powder particles are preferably coated with an insulating layer, which ensures that the return ring segment RRS consists of countless, individually insulating iron particles and thus has reduced electrical conductivity.In this way, eddy current losses can be reduced, which can have a beneficial effect on the performance of the axial flux machine.

[0042] The return ring segments RRS are fixed or fastened to the flange FL via the adhesive layer AS between the flange FL and the return ring segments RRS. This can have a positive effect on the structural rigidity of the rotor RO. Increased structural rigidity of the rotor RO reduces the torsion of the rotor RO caused by a magnetic field to a stator arranged at an air gap from the rotor RO. Due to the reduced torsion, the air gap between the stator and rotor RO can be reduced, which can have a positive effect on the performance of the axial flux machine.

[0043] An intermediate element ZE with a ferritic or martensitic structure is arranged between two return ring segments RRS arranged adjacent to one another in the circumferential direction of the flange FL. In this way, if a distance or gap SP exists between two return ring segments RRS, this gap SP can be closed by the intermediate element ZE, so that a continuous magnetic return flux in the circumferential direction of the rotor RO or flange FL can be enabled via the return ring RR. Consequently, the magnetic flux within the rotor RO can be increased in this way, which can have a beneficial effect on the torque. An increased torque can have a beneficial effect on the performance of the axial flux machine. Furthermore, the return ring segments RRS can be securely fixed in their position on the flange FL using the intermediate elements ZE.

[0044] The intermediate element ZW has a T-shaped design with respect to a radial direction of the rotor RO. The upright web of the T-shaped intermediate element ZE runs in the radial direction of the rotor RO. The free end of the upright web of the T-shaped intermediate element ZE points inwards in the radial direction of the rotor RO. The crossbeam ends QBE of the T-shaped intermediate element ZE preferably engage in corresponding recesses AN of the return ring segments RRS. Thus, when the intermediate element ZE is fixed to the flange FL, the crossbeam of the T-shaped intermediate element ZE acts as a stop for the return ring segment RRS resting against the intermediate element ZE in the radial direction of the rotor RO.Due to the recess AN in the return ring elements RRS, these can be shifted further outwards in the radial direction of the rotor RO, which can have a beneficial effect on the magnetic return flux and thus on the performance of the axial flux machine.

[0045] An adhesive layer AS is applied to the return ring segments RRS. Magnets MA are firmly attached to the return ring segments RRS via the adhesive layer AS. This can have a beneficial effect on the structural rigidity of the rotor RO. Increased structural rigidity of the rotor RO reduces the torsion of the rotor RO caused by a magnetic field relative to a stator arranged at an air gap. Due to the reduced torsion, the air gap between the stator and rotor RO can be reduced, which can have a beneficial effect on the performance of the axial flux machine.

[0046] The magnets MA are clamped via a multi-part connecting device VE between the outer collar KR and the clamping device VE, thus securing them to the flange FL. The clamping device VE comprises clamping plates VP and corresponding screws SB. One number of clamping plates VP corresponds to one number of magnets MA.

[0047] Figures 2 to 6 show a method for manufacturing the rotor RO. Figures 2 to 6 each show a longitudinal section through the rotor RO, illustrating various manufacturing steps.

[0048] Fig. 2 shows a longitudinal section through the rotor RO, with the adhesive layer AS applied to the inner side IS of the flange FL. The adhesive layer AS does not necessarily have to be applied to the inner side IS; it can also be applied to the return ring segments RSS, if present at all.

[0049] Fig. 3 shows the longitudinal section through the rotor RO, showing the arrangement of the return ring segments RSS on the flange FL. The provision is that the return ring segments RSS are first displaced in the axial direction of the flange FL (arrow a) and then, at the level of the collar KR, displaced in the radial direction of the flange FL towards the outer collar KR (arrow b), so that the return ring segments RSS at least partially or sectionally rest on the inner side KIS of the outer collar KR. This is followed by a displacement in the axial direction of the flange FL up to the inner side IS (arrow c). The return ring segments RSS can thus be placed further outwards in the radial direction of the flange FL, which can have a beneficial effect on the magnetic return flux and the torque, which in turn is beneficial for the performance of the axial flux machine.

[0050] Figure 4 shows a longitudinal section through the rotor RO, with an adhesive layer AS applied to the return ring segments RSS. The adhesive layer AS does not necessarily have to be applied to the return ring segments RSS. It can also be applied to the magnets MA, if present at all.

[0051] Fig. 5 shows the longitudinal section through the rotor RO, wherein the magnets MA are arranged on the return ring segments RSS. It is intended that the magnets MA are first displaced in the axial direction of the flange FL (arrow d) and at the level of the collar KR are displaced in the radial direction of the flange FL in the direction of the outer collar KR (arrow e). It can also be seen that the outer collar KR is designed as a projection formed in the axial direction of the flange FL with a rear locking lug HRN directed inward in the radial direction. In other words, the outer collar KR has a distal end in the axial direction of the flange FL. Starting from the distal end, the outer collar KR has an undercut, so that a rear locking lug HRN directed inward in the radial direction of the flange FL is formed.The HRN locking lug allows the magnet to engage the undercut and thus be positively and / or non-positively fixed to the flange FL via the HRN locking lug and the VE clamping device. Furthermore, the HRN locking lug allows the magnets MA to be positioned largely outward in a radial position of the rotor RO, which is advantageous for the torque and thus the performance of the axial flux machine.

[0052] Fig. 6 shows the longitudinal section through the rotor RO, wherein the bracing device VE is mounted and the magnets MA are fixed positively and / or non-positively on the flange FL. The bracing device VE comprises the bracing plate VP, which is connected to the flange FL via a screw SB. The bracing plate VP has a bevelled side on a side facing the magnet MA, which is also directed outwards in the radial direction of the rotor RO. The magnet MA also has a correspondingly bevelled side. Furthermore, the rear locking lug HRN has a bevelled side on a side facing the magnet MA, which is also directed inwards in the radial direction of the rotor RO. The magnet MA also has a correspondingly bevelled side. The magnets MA can thus be securely fixed on the flange FL.

[0053] Fig 7 shows a top view of the rotor RO as it looks in the assembled state.

Claims

Patent claims 1. Rotor (RO) for an axial flux machine of an at least partially electrically driven motor vehicle, comprising a circular ring-shaped flange (FL) with an outer collar (KR), a bracing device (VE) arranged at a distance from the outer collar (KR) in the radial direction of the flange (FL) and connected to the flange (FL) in a force-locking and / or form-locking manner, a plurality of magnets (MA) which are fixed between the outer collar (KR) and the bracing device (VE) via the bracing device (VE), and a return ring (RR) arranged between the plurality of magnets (MA) and the flange (FL), which return ring is formed from a plurality of return ring segments (RRS) in the circumferential direction of the flange (FL), and the return ring segments (RRS), with respect to a radial direction of the flange (FL), at least partially and / or in sections abut against an inner side (KIS) of the collar which is directed inwards in the radial direction of the flange (FL).

2. Rotor according to claim 1, characterized in that an intermediate element (ZE) made of and / or with a ferritic or martensitic structure is arranged between two return ring segments (RRS) arranged adjacent to one another in the circumferential direction of the flange (FL).

3. Rotor according to claim 2, characterized in that the intermediate element (ZE) has a T-shaped configuration with respect to a radial direction of the rotor (RO).

4. Rotor according to one of claims 2 or 3, characterized in that the intermediate element (ZE) is connected to the flange (FM) in a form-fitting and / or force-fitting manner.

5. Rotor according to one of the preceding claims, characterized in that the plurality of return ring segments (RRS) are arranged at least in sections in a materially bonded manner on the flange (FL).

6. Rotor according to one of the preceding claims, characterized in that the plurality of magnets (MA) are arranged at least in sections in a materially bonded manner on the return ring segments (RRS).

7. Rotor according to one of the preceding claims, characterized in that the outer collar (KR) is designed as a projection formed in the axial direction of the flange (FL) with a rear locking nose (HRN) directed inwards in the radial direction.

8. Rotor according to one of the preceding claims, characterized in that the outer collar (KR) is formed continuously in the circumferential direction of the flange (FL).

9. Rotor according to one of claims 1 to 7, characterized in that the outer collar (KR) has at least one interruption with respect to the circumferential direction of the flange (FL).

10. Rotor according to one of the preceding claims, characterized in that the bracing device (VE) is designed in several parts. 11 . Axial flux machine with a rotor (RO) according to one of the preceding claims.

12. A method for producing a rotor (RO) according to one of claims 1 to 10, comprising the steps: - Providing a flange (FL) with an outer collar (KR); - arranging return ring segments (RRS) on the flange (FL), whereby the return ring segments (RRS) are first displaced in the axial direction of the flange (FL) and are displaced at the level of the collar (KR) in the radial direction of the flange (FL) towards the outer collar (KR); - Arranging the plurality of magnets (MA) on the return ring segments (RRS); - Fastening at least one clamping device (VE) on the flange (VL), whereby the magnets (MA) are fixed in a form-fitting manner on the flange (FL) via the at least one clamping device (VE) and the outer collar (KR).

Images