Axial flux motor thermoplastic integrated support and production method

Abstract

The invention belongs to the technical field of motor manufacturing, and discloses an axial flux motor thermoplastic integrated support and a production method.The axial flux motor thermoplastic integrated support comprises an inner support which comprises a main body formed by compression molding of a composite material, a tool preformed hole formed in the center of the main body and used for installation and machining, and a plurality of supporting rods arranged on the outer wall of the main body at equal intervals; the support rod extends along the radius direction of the main body; the plurality of magnetic steel sheets are abutted between two adjacent supporting rods, and form a disc-shaped structure with the plurality of supporting rods; and the sheath is made of a composite material, and the hoop sleeve is wound on the outer wall of the disc-shaped structure and applies a pre-tightening force. The motor rotor is integrally formed by adopting a composite material, and the magnetic steel sheets are fixed, so that the purposes of collision prevention, light weight, high rotating speed and low vortex loss are achieved, and high-speed rotation of the motor rotor is realized.

Description

Technical Field

[0001] The invention belongs to the technical field of motor manufacturing, and in particular relates to an axial flux motor thermoplastic integrated bracket and a production method. Background Art

[0002] There is a clear trend towards higher speeds in new energy vehicle drive motors. At the same time, high speeds cause the centrifugal force on the rotor to increase, posing challenges to the stability and safety of the motor.

[0003] Traditional shaft flux motor brackets are mostly made of non-magnetic metal or glass fiber / epoxy composite materials, and the sheath is made of carbon fiber / epoxy. In the past, the production of motors often used a thermosetting winding process. The process of wet winding sheaths requires the preparation of resins, production, curing, and mechanical processing, which is not only inefficient but also affects the product yield. At present, the motor rotors on the market use metal brackets with large inertia. Under high speed / high frequency conditions, the stator windings will produce obvious skin effect and proximity effect, which will lead to serious eddy losses. These losses will be converted into heat and transferred outward, but will not improve hysteresis loss and AC loss. These losses often appear on the outside of the magnetic steel, the metal sheath, the surface of the stator winding, etc. We must ensure high power density when preparing high-speed motor rotors, that is, the weight of the motor bracket should be as light as possible and the volume should be small. If a glass fiber epoxy bracket is used, the bonding force between the bracket and the magnetic steel is poor, and the glass fiber epoxy bracket has low stiffness. At the same time, the bracket and the sheath belong to two different material systems. The bracket and the sheath of the bracket cannot avoid the centrifugal force caused by the high-speed operation of the shaft flux motor, which will cause the motor rotor to deform. For production requirements, the production efficiency is low and the production cost is increased.

[0004] Therefore, the present application designs an axial flux motor thermoplastic integrated bracket and a production method to solve the above-mentioned technical problems. Summary of the invention

[0005] In order to solve the above technical problems, the present invention proposes an axial flux motor thermoplastic integrated bracket and a production method, and manufactures an integrated bracket by integrated molding of composite materials to achieve the purposes of anti-collision, lightweight, high speed and anti-vortex loss.

[0006] To achieve the above object, the present invention provides an axial flux motor thermoplastic integrated bracket, comprising:

[0007] The inner bracket comprises a main body formed by compression molding of composite materials, the center of the main body is provided with a tooling reserved hole for installation and processing, and the outer wall of the main body is provided with a plurality of support rods at equal intervals, and the support rods extend along the radius direction of the main body;

[0008] A plurality of magnetic steel sheets, wherein the magnetic steel sheets are abutted between two adjacent support rods and form a disc-shaped structure with the plurality of support rods;

[0009] The sheath is made of composite material, and the hoop is wrapped around the outer wall of the disc-shaped structure and exerts a pre-tightening force.

[0010] Preferably, the magnetic steel sheet is arranged in a fan shape, the inner circle of the magnetic steel sheet is in abutment with the outer wall of the main body, and the outer circle of the magnetic steel sheet is aligned with the end of the support rod away from the main body.

[0011] Preferably, a plurality of first protrusions are fixedly connected to the inner ring of the magnetic steel sheet, and a plurality of first grooves adapted to the first protrusions are provided on the outer wall of the main body, and the first protrusions are embedded and clamped in the first grooves.

[0012] Preferably, second protrusions are respectively provided on both side edges of the magnetic steel sheet, and second grooves matched with the second protrusions are provided on both sides of the support rod, and the second protrusions are embedded and clamped in the second grooves.

[0013] Preferably, the composite material comprises carbon fiber / PEEK mixed prepreg.

[0014] Preferably, a plurality of connection holes are provided on the main body, and the plurality of connection holes are arranged around the tooling reserved hole.

[0015] A method for producing an axial flux motor thermoplastic integrated bracket comprises the following steps:

[0016] Premix the composite materials that meet the requirements, and then make the inner bracket through mold pressing;

[0017] Clean the manufactured inner bracket to maintain the molding quality and facilitate the subsequent production process;

[0018] Select a magnetic steel sheet of corresponding size and clamp it between adjacent support rods on the inner bracket to form a disc-shaped structure;

[0019] A composite material sheath is wound around the outer wall of the disc-shaped structure by an in-situ fixing technology, and a pre-tightening force is applied;

[0020] The components are fixed by high temperature of laser.

[0021] Preferably, the inner support molding process comprises the following steps:

[0022] Adding a composite material consisting of multiple layers of composite carbon fiber / PEEKK mixed prepreg layer by layer into the preheated mold;

[0023] The mold after adding the composite material is closed, and then the mold is pressurized;

[0024] Apply high temperature and high pressure to consolidate the composite material in the mold, and then keep it at a constant temperature;

[0025] After sufficient heat preservation time, the hardened composite material in the mold is demoulded to obtain the required inner bracket.

[0026] Preferably, the upper and lower molds are combined in the mold closing process, and the mold closing is carried out in a fast-first-then-slow manner.

[0027] Preferably, during the high-temperature heating and heat preservation process, the mold is wrapped with a heat-insulating material to maintain the overall uniformity of the product.

[0028] Compared with the prior art, the present invention has the following advantages and technical effects: the present invention discloses an axial flux motor thermoplastic integrated bracket and a production method, by wrapping a sheath made of composite material around a disc structure composed of an inner bracket and magnetic steel, and applying a high preload force, it can ensure that the magnetic steel sheet is stable and does not shift during high-speed rotation; the integrated bracket made of composite material is not prone to eddy current loss during high-speed rotation, thereby avoiding power loss and overheating problems of the motor and improving the efficiency and performance of the motor; the inner bracket and the sheath are made of composite material, and then the magnetic steel sheet is wrapped and fixed, which helps to reduce the weight of the rotor and can better match the high-speed requirements of the motor, thereby improving the motor performance. The combination of the two can achieve close combination of the magnetic steel sheet and the bracket under high temperature and high preload force, and the composite material sheath and the bracket are integrated to achieve high-speed rotation of the motor rotor.

[0029] The present invention adopts composite material integrated molding to fix magnetic steel sheets to achieve the purpose of anti-collision, light weight, high speed and low eddy loss, and realizes high-speed rotation of the motor rotor. BRIEF DESCRIPTION OF THE DRAWINGS

[0030] The drawings constituting a part of the present application are used to provide a further understanding of the present application. The illustrative embodiments and descriptions of the present application are used to explain the present application and do not constitute an improper limitation on the present application. In the drawings:

[0031] Figure 1 This is an axial view of the integrated composite material stent and sheath of the present invention;

[0032] Figure 2 This is a front view of the integrated composite material stent and sheath of the present invention;

[0033] Figure 3 This is a schematic diagram of the axial view of the inner support of the present invention;

[0034] Figure 4 It is an axial view of the magnetic steel sheet of the present invention;

[0035] In the figure: 1. inner bracket; 11. main body; 12. reserved hole for tooling; 13. first groove; 14. support rod; 15. connecting hole; 16. second groove; 2. magnetic steel sheet; 21. first protrusion; 22. second protrusion; 3. sheath. DETAILED DESCRIPTION

[0036] The following will be combined with the drawings in the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0037] In order to make the above-mentioned objects, features and advantages of the present invention more obvious and easy to understand, the present invention is further described in detail below with reference to the accompanying drawings and specific embodiments.

[0038] Reference Figure 1-Figure 4 As shown, this embodiment provides an axial flux motor thermoplastic integrated bracket, comprising:

[0039] The inner bracket 1 comprises a main body 11 formed by compression molding of a composite material, a tooling reserved hole 12 is arranged at the center of the main body 11 for installation and processing, and a plurality of support rods 14 are arranged at equal intervals on the outer wall of the main body 11, and the support rods 14 extend along the radial direction of the main body 11;

[0040] A plurality of magnetic steel sheets 2, wherein the magnetic steel sheets 2 are abutted between two adjacent support rods 14, and form a disc-shaped structure with the plurality of support rods 14;

[0041] The sheath 3 is made of composite material, and the hoop is wrapped around the outer wall of the disc-shaped structure and applies a pre-tightening force.

[0042] The present invention discloses an axial flux motor thermoplastic integrated bracket and a production method. By wrapping a sheath 3 made of composite material around a disc-shaped structure composed of an inner bracket 1 and magnetic steel, and applying a high preload force, it can be ensured that the magnetic steel sheet 2 is stable and does not shift during high-speed rotation; the integrated bracket made of composite material is not prone to eddy current loss during high-speed rotation, thereby avoiding power loss and overheating problems of the motor and improving the efficiency and performance of the motor; the inner bracket 1 and the sheath 3 are made of composite material, and then the magnetic steel sheet 2 is wrapped and fixed, which helps to reduce the weight of the rotor and can better match the high-speed requirements of the motor, thereby improving the motor performance. The combination of the two can achieve close combination of the magnetic steel sheet 2 and the bracket under high temperature and high preload force, and the composite sheath 3 and the bracket are integrated to achieve high-speed rotation of the motor rotor.

[0043] Furthermore, the main body 11 of this embodiment can also be manufactured by injection molding technology.

[0044] In a further optimized solution, the magnetic steel sheet 2 is arranged in a fan shape, the inner circle of the magnetic steel sheet 2 is in contact with the outer wall of the main body 11, and the outer circle of the magnetic steel sheet 2 is aligned with the end of the support rod 14 away from the main body 11. The cross-sectional shape of the magnetic steel sheet 2 and the support rods 14 adjacent to the inner bracket 1 allow the magnetic steel sheet 2 to fit tightly between the support rods 14, so that the magnetic steel sheet 2 can fit tightly with the main body 11 and the support rods 14 respectively, which is convenient for fixation.

[0045] In a further optimized solution, the inner ring of the magnetic steel sheet 2 is fixed with a plurality of first protrusions 21, and the outer wall of the main body 11 is provided with a plurality of first grooves 13 adapted to the first protrusions 21, and the first protrusions 21 are embedded and snapped into the first grooves 13; the two sides of the magnetic steel sheet 2 are respectively provided with second protrusions 22, and the two sides of the support rod 14 are provided with second grooves 16 adapted to the second protrusions 22, and the second protrusions 22 are embedded and snapped into the second grooves 16. The first protrusions 21 and the second protrusions 22 on the outer wall of the magnetic steel sheet 2 are mainly used for positioning. When it is installed into the inner bracket 1, the second protrusions 22 slide into the second grooves 16 between the adjacent support rods 14, so that the front and rear end surfaces of the magnetic steel sheet 2 and the inner bracket 1 are aligned. When the magnetic steel sheet 2 is snapped into place, the inner ring of the magnetic steel sheet 2 fits the outer wall of the main body 11, and the first protrusions 21 are snapped into the first grooves 13, so that the magnetic steel sheet 2 can be tightly fixed to the inner bracket 1, and it is also convenient for the sheath 3 to fix the inner bracket 1 and the magnetic steel sheet 2.

[0046] In a further optimized solution, the composite material includes carbon fiber / PEEK mixed prepreg. The composite material of this embodiment is preferably carbon fiber / PEEK mixed prepreg, which has light weight, high structural strength, can be easily molded as a whole, and has low production cost.

[0047] Furthermore, the composite material of this embodiment can also be made of carbon fiber / PPS prepreg.

[0048] In a further optimized solution, a plurality of connection holes 15 are provided on the main body 11, and the plurality of connection holes 15 are arranged around the tooling reserved hole 12. The connection holes 15 are arranged around the tooling reserved hole 12 to facilitate connection with the high-speed motor.

[0049] A method for producing an axial flux motor thermoplastic integrated bracket comprises the following steps:

[0050] Premixing a composite material that meets the requirements, and then molding the inner bracket 1 through a mold; selecting a composite material of carbon fiber / PEEKK mixed prepreg according to the requirements, loading the composite material into a preheated mold, and molding it through a set pressure to obtain the required inner bracket 1;

[0051] Clean the manufactured inner bracket 1 to maintain the molding quality and facilitate the subsequent production process; take the molded inner bracket 1 out of the mold, and clean the inner bracket 1 to remove defects such as burrs and rough edges, so that the surface of the inner bracket 1 is smooth to facilitate subsequent processing;

[0052] Select a magnetic steel sheet 2 of corresponding size, and clamp it between adjacent support rods 14 on the inner bracket 1 to form a disc-shaped structure; fix the selected magnetic steel sheet 2 along the adjacent support rods 14 of the inner bracket 1, so that the second protrusion 22 and the second groove 16 are limited and fixed, and the first protrusion 21 and the first groove 13 are limited and fixed, so that multiple magnetic steel sheets 2 are arranged in a circle along the ring. In this solution, the combination between the magnetic steel sheet 2 and the thermoplastic inner bracket 1 is simple and quick, and no mechanical assembly is required;

[0053] The composite material sheath 3 is wound around the outer wall of the disc-shaped structure by in-situ fixing technology, and a pre-tightening force is applied; the inner bracket 1 with the magnetic steel sheet 2 installed is wound with carbon fiber / PEEKK mixed prepreg on the surface by "in-situ consolidation technology" to form a sheath 3;

[0054] The components are fixed by laser high temperature. The excellent bonding property between the carbon fiber / PEEKK prepreg materials is utilized to tightly bond the sheath 3 and the end of the support rod 14 under laser high temperature conditions to form a whole, thereby fixing the magnetic steel sheet 2.

[0055] Furthermore, during the forming process of the inner bracket 1, the width of the prepreg is first measured, and the laser spot is adjusted to make the width of the laser spot consistent with the width of the prepreg. The same width can ensure that the prepreg is fully bonded; the cylinder installed on the equipment is adjusted to accurately adjust the winding tension.

[0056] Furthermore, the winding process of the sheath 3 utilizes the resin matrix of the carbon fiber / PEEKK prepreg itself to be combined under laser high temperature conditions.

[0057] Furthermore, during the winding process of the sheath 3, the disc-shaped structure is installed on the high-speed motor rotor, the surface of the magnetic steel and the inner bracket 1 is cleaned with an air source, a layer of carbon fiber / PEEKK prepreg is wrapped around the surface of the magnetic steel and the inner bracket 1, the laser is turned on, and the pressure at the pressure roller is increased. The carbon fiber / PEEKK prepreg at the pressure roller is tightly bonded to the upper carbon fiber / PEEKK prepreg under high temperature and high tension. The prepreg wrapped on the surface of the magnetic steel is made of the same material as the bracket, so it is bonded to form an integral structure.

[0058] Further optimizing the scheme, the molding process of the inner bracket 1 includes the following steps:

[0059] Add a composite material composed of multiple layers of composite carbon fiber / PEEKK mixed prepreg layer by layer into the preheated mold; add a specified amount of multi-layer composite carbon fiber / PEEKK mixed prepreg and short-cut prepreg into the high-strength, high-precision, high-temperature resistant mold as needed, and the amount of added material directly affects the density and size of the product. If the amount of added material is too much, the product will have thick burrs, poor dimensional accuracy, difficult demoulding, and may damage the mold; if the amount of added material is too little, the product will be loose and have poor gloss, and even cause material shortage and produce waste;

[0060] The mold after adding the composite material is closed, and then the mold is pressurized; the upper and lower molds are combined in the mold closing process, and the mold closing is carried out in a fast-first-then-slow manner; a hydraulic press with controllable molding pressure is used, and the upper and lower molds are closed after the addition is completed. When closing the mold, fast speed is used first, and then slow speed is changed when the upper and lower molds are in contact. The fast-first-then-slow operation method is conducive to shortening non-production time, preventing mold scratches, and preventing the raw materials in the mold groove from being carried out by air due to too fast mold closing, and even causing the insert to be displaced, and the slot of the toothed support rod 14 is damaged. After the mold is closed, pressure can be applied. The molding pressure is higher than that of other process methods, and a high-strength and high-temperature resistant bracket can be obtained;

[0061] Apply high temperature and high pressure to consolidate the composite material in the mold, and then keep it at a constant temperature; during the high-temperature heating and insulation process, wrap the mold with insulation material to maintain the overall uniformity of the product; after sufficient insulation time, demould the hardened composite material in the mold to obtain the required inner bracket 1; after applying high temperature and high pressure, we use insulation cotton to heat and insulate around the mold to prevent uneven heating and prevent heat dissipation around the periphery from seriously affecting the overall uniformity of the product. The carbon fiber / PEEKK mixed prepreg and the chopped prepreg are fully infiltrated, and the molding material fills the mold cavity. With the increase of insulation time, the resin system reacts with the carbon fiber. After the insulation is over, the product is cooled to a certain temperature and demolded to obtain a composite bracket with the required physical and mechanical properties.

[0062] In the description of the present invention, it should be understood that the terms "longitudinal", "lateral", "up", "down", "front", "back", "left", "right", "vertical", "horizontal", "top", "bottom", "inside" and "outside" etc., indicating orientations or positional relationships, are based on the orientations or positional relationships shown in the accompanying drawings, and are only for the convenience of describing the present invention, and do not indicate or imply that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore should not be understood as a limitation on the present invention.

[0063] The embodiments described above are only descriptions of the preferred modes of the present invention, and are not intended to limit the scope of the present invention. Without departing from the design spirit of the present invention, various modifications and improvements made to the technical solutions of the present invention by ordinary technicians in this field should all fall within the protection scope determined by the claims of the present invention.

Claims

1. A thermoplastic integrated bracket for an axial flux motor, characterized in that: include: The inner bracket (1) comprises a main body (11) formed by compression molding of a composite material, wherein a tooling reserved hole (12) is arranged at the center of the main body (11) for installation and processing, and a plurality of support rods (14) are arranged at equal intervals on the outer wall of the main body (11), and the support rods (14) extend along the radial direction of the main body (11); A plurality of magnetic steel sheets (2), wherein the magnetic steel sheets (2) are abutted between two adjacent support rods (14) to form a disc-shaped structure with the plurality of support rods (14); The sheath (3) is made of a composite material, and the hoop is wound around the outer wall of the disc-shaped structure and applies a pre-tightening force.

2. The thermoplastic integrated bracket of the axial flux motor according to claim 1, characterized in that: The magnetic steel sheet (2) is arranged in a fan shape, the inner ring of the magnetic steel sheet (2) is in contact with the outer wall of the main body (11), and the outer ring of the magnetic steel sheet (2) is aligned with the end of the support rod (14) away from the main body (11).

3. The thermoplastic integrated bracket of the axial flux motor according to claim 2, characterized in that: The inner ring of the magnetic steel sheet (2) is fixedly connected with a plurality of first protrusions (21), the outer wall of the main body (11) is provided with a plurality of first grooves (13) adapted to the first protrusions (21), and the first protrusions (21) are embedded and clamped in the first grooves (13).

4. The thermoplastic integrated bracket for an axial flux motor according to claim 2, characterized in that: Second protrusions (22) are respectively arranged on both side edges of the magnetic steel sheet (2), and second grooves (16) adapted to the second protrusions (22) are arranged on both sides of the support rod (14), and the second protrusions (22) are embedded and clamped in the second grooves (16).

5. The thermoplastic integrated bracket for an axial flux motor according to claim 1, characterized in that: The composite material includes carbon fiber / PEEK mixed prepreg.

6. The thermoplastic integrated bracket for an axial flux motor according to claim 1, characterized in that: The main body (11) is provided with a plurality of connection holes (15), and the plurality of connection holes (15) are arranged around the tooling reserved hole (12).

7. A method for producing an axial flux motor thermoplastic integrated bracket, according to any one of claims 1 to 6, characterized in that The following steps are involved: Premixing a composite material that meets the requirements, and then molding the inner bracket (1) through a mold; Cleaning the manufactured inner bracket (1) to maintain the molding quality and facilitate the subsequent production process; Selecting a magnetic steel sheet (2) of corresponding size and clamping it between adjacent support rods (14) on the inner bracket (1) to form a disc-shaped structure; A composite material sheath (3) is wound around the outer wall of the disc-shaped structure by an in-situ fixing technique, and a pre-tightening force is applied; The components are fixed by high temperature of laser.

8. The method for producing the thermoplastic integrated bracket of the axial flux motor according to claim 7, characterized in that: The molding process of the inner bracket (1) comprises the following steps: Adding a composite material consisting of multiple layers of composite carbon fiber / PEEKK mixed prepreg layer by layer into the preheated mold; The mold after adding the composite material is closed, and then the mold is pressurized; Apply high temperature and high pressure to consolidate the composite material in the mold, and then keep it at a constant temperature; After a sufficient period of heat preservation, the hardened composite material in the mold is demoulded to obtain the required inner bracket (1).

9. The method for producing the thermoplastic integrated bracket of the axial flux motor according to claim 8, characterized in that: In the mold closing process, the upper and lower molds are combined, and the mold closing is carried out in a fast-first-slow-later manner.

10. The method for producing the thermoplastic integrated bracket of the axial flux motor according to claim 8, characterized in that: During the high-temperature heating and insulation process, the mold is wrapped with insulation material to maintain the overall uniformity of the product.

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