Motor and method for manufacturing same

Abstract

The invention relates to a motor and a method for manufacturing the motor, the motor comprises a casing, a stator, a rotor, a front end cover and a rear end cover, the stator comprises a stator core and a stator winding, and the stator core is formed by splicing and enclosing a plurality of stator splicing blocks along the circumferential direction; each stator block comprises a stator magnetic core block, a stator coil holder block and a stator winding, and the stator coil holder block is coated and formed on the surface of the stator magnetic core block and is used for providing insulation isolation for the stator winding; each stator magnetic core block comprises a stator yoke part and a stator tooth, and a stator winding is wound on the stator tooth; the two circumferential ends of the stator yoke part of each stator block are used for being spliced and enclosed with the stator yoke part of the adjacent stator block, so that the stator yoke parts are spliced and enclosed to form a cylindrical outer wall of the stator core, and the inner ends of the stator teeth are spliced and enclosed to form a stator central through hole; and winding grooves are formed between adjacent stator teeth. According to the invention, the winding process is simpler, and the slot fullness rate of the winding slot is improved.

Description

Technical Field

[0001] This invention relates to the field of electric motor technology, and in particular to an electric motor and a method for manufacturing the electric motor. Background Technology

[0002] The operating mechanical characteristics of an electric motor are its external characteristics, that is, the mechanical characteristics that the motor can output. Specifically, given the rated voltage and rated load, the motor can output the corresponding torque, speed, and required current. The operating quality characteristics of an electric motor are its internal characteristics, controlled by certain important factors. These include the motor's cogging torque, torque ripple, harmonics, induced electromotive force and waveform, maximum output power, noise, and vibration.

[0003] At present, based on the miniaturization of motors, improving the operating quality characteristics of motors to increase power density and maximum output power, while reducing motor noise and vibration to provide users with better comfort, has become an important topic in motor design. Summary of the Invention

[0004] The purpose of this invention is to provide a motor that achieves miniaturization, optimizes motor power density, and increases maximum output power, as well as a method for manufacturing the motor.

[0005] The first aspect of the present invention provides an electric motor, including a housing, a stator, a rotor, a front end cover and a rear end cover, wherein the stator includes a stator core and a stator winding, and the stator core is formed by splicing and enclosing a plurality of stator blocks along the circumferential direction; Each stator assembly includes a stator core block, a stator wire frame block, and a stator winding. The stator wire frame block is overmolded onto the surface of the stator core block to provide insulation to the stator winding. The stator core block, the stator wire frame block, and the corresponding stator winding form a whole of the stator assembly. Each stator core block includes an arc-shaped stator yoke and stator teeth extending inward from the stator yoke, with one stator winding wound around the stator teeth; the circumferential ends of the stator yoke of each stator block are used to splice and enclose with the stator yokes of adjacent stator blocks, so that the spliced ​​stator yokes form the cylindrical outer wall of the stator core, and the inner ends of the stator teeth splice and enclose to form the central through hole of the stator; a winding groove is formed between adjacent stator teeth; The housing encloses the cylindrical outer wall of the stator core, and both ends of the housing are fixedly connected to the front end cover and the rear end cover, respectively. The rotor passes through the central through hole of the stator and is rotatable relative to the stator, the front end cover, and the rear end cover.

[0006] Preferably, after the stator core is formed by splicing the stator blocks circumferentially, and the winding slots accommodate the stator windings, the slot fill factor of the winding slots reaches 85%.

[0007] Preferably, the stator frame block is an insulating film layer that is formed over the outer wall of the stator core block, and the thickness of the slot insulating film layer of the stator frame block is in the range of 0.2mm-0.3mm.

[0008] Preferably, the stator yoke is provided with a connecting protrusion and a connecting recess on both sides, and the connecting protrusion of the stator yoke of each stator block engages with the connecting recess of the adjacent stator block, so that several stator blocks are fixedly connected and enclosed to form the whole of the stator.

[0009] Furthermore, the rotor includes a rotor core, a magnetic assembly, and a central shaft, the magnetic assembly being embedded inside the rotor core; the rotor core has a hollow hole, the central shaft passing through the hollow hole and being fixed to the rotor core; the centerline of the central shaft is collinear with the axial centerline of the rotor core.

[0010] Preferably, the rotor core includes a first axial segment and a second axial segment along the axial direction, and the magnetic poles at the first axial end and the magnetic poles at the second axial end are offset in the circumferential direction.

[0011] Preferably, the magnetic poles of the first axial segment and the magnetic poles of the second axial segment are offset by 10 degrees in the circumferential direction.

[0012] Preferably, the stator core is assembled from 9 stator blocks and has 9 stator teeth and 9 stator windings. Each stator winding is wound around one stator tooth, and 9 winding slots are formed between the 9 stator teeth. The rotor has a total of 6 magnetic poles, which are evenly distributed along the circumference of the rotor.

[0013] Furthermore, the motor also includes a rotor balancing component and an adjusting shim disposed at the junction of the central shaft and the two ends of the rotor core; at least one end of the rotor core is provided with the rotor balancing component, and the other end is provided with the adjusting shim.

[0014] A second aspect of the present invention provides a method for manufacturing an electric motor, used to manufacture the electric motor described in the first aspect above; the method for manufacturing the electric motor includes the following steps: S1. Preparation of stator modules: A stator wire frame block is formed by covering the surface of a stator core block and then covering the stator teeth of the stator core block with the stator wire frame block; then a stator winding is wound onto the stator teeth to obtain a stator assembly. Prepare several stator modules according to the steps described above for preparing one stator module; S2, Enclosed splicing: The stator yoke or stator teeth of a stator assembly are spliced ​​together with the stator yoke or stator teeth of an adjacent stator assembly; several stator assemblies are spliced ​​together to form a stator core with several winding slots; the inner ends of several stator teeth are spliced ​​together to form a central through hole in the stator, and several stator yokes are spliced ​​together to form the cylindrical outer wall of the stator core; thus, the entire stator is prepared. S3, Assembly housing: The housing is fitted into the stator core, so that the housing covers the cylindrical outer wall of the stator core; S4. Assemble the rotor and install the end cover: The rotor is passed through the central through-hole of the stator; The front cover and the rear cover are fixed to the two ends of the housing respectively; and the rotor is made rotatable relative to the stator, the front cover and the rear cover.

[0015] Preferably, step S2 further includes: providing connecting protrusions and connecting recesses on both sides of the stator yoke; engaging the connecting protrusions and connecting recesses of the stator yokes of adjacent stator blocks, thereby fixing and connecting several stator blocks together to form the stator assembly; and welding the connection points of adjacent connecting protrusions and connecting recesses.

[0016] The motor of the present invention adopts a structure in which stator blocks are spliced ​​together to form a stator. The stator winding of each stator block can be easily wound to the stator teeth of its corresponding stator block, which simplifies the winding process. While controlling the overall miniaturization of the product, it can also significantly improve the slot fill factor of the winding slot and increase the power density of the motor, thereby increasing the maximum output power of the motor. Attached Figure Description

[0017] Figure 1 This is a three-dimensional schematic diagram of an electric motor provided in Embodiment 1 of the present invention; Figure 2 yes Figure 1 An exploded view of the motor housing, stator, rotor, front cover, and rear cover. Figure 3 yes Figure 1 A longitudinal section diagram of the motor shown. Figure 4 This is a schematic diagram of the structure of the motor of the present invention after the housing is removed; Figure 5 This is a schematic diagram of the structure of the motor provided by the present invention, after the stator blocks are assembled and enclosed, the stator windings are removed; Figure 6 This is a three-dimensional schematic diagram of a stator block in the stator core of the motor provided by the present invention after the stator windings have been removed; Figure 7 yes Figure 6 An exploded view of the stator core block and stator wire frame block of a stator assembly is shown. Figure 8 This is a schematic diagram showing the connection structure of adjacent stator core blocks after the stator modules of the motor provided by the present invention are assembled and enclosed, with the stator wire frame blocks removed. Figure 9 This is a top view of a stator core block in the stator assembly of the motor provided by the present invention; Figure 10 This is a three-dimensional schematic diagram of the rotor of the motor provided by the present invention; Figure 11 yes Figure 10 A cross-sectional schematic diagram of the rotor shown. Figure 12 This is a flowchart illustrating a method for manufacturing an electric motor according to Embodiment 2 of the present invention. Detailed Implementation

[0018] The present invention will now be further described with reference to the accompanying drawings and embodiments.

[0019] Example 1 Please see Figure 1 , Figure 2 and Figure 3 Embodiment 1 of the present invention provides an electric motor 100, including a housing 10, a stator 20, a rotor 30, a front end cover 40, and a rear end cover 50. The stator 20 includes a stator core and a stator winding 210.

[0020] Please see Figure 2 and Figure 3The stator core is formed by circumferentially joining several stator blocks 21. Specifically, each stator block 21 includes a stator core block 211, a stator wire frame block 212, and a stator winding 210. In this embodiment, the stator core block 211, the stator wire frame block 212, and the corresponding stator winding 210 form a whole stator block 21. The stator wire frame block 212 is overmolded onto the surface of the stator core block 211. The stator wire frame block 212 provides insulation for the stator winding 210. Each stator core block 211 includes an arc-shaped stator yoke 214 and stator teeth 213 extending inward from the stator yoke 214. One stator tooth 213 is wound with one stator winding 210. The stator wire frame block 212 covers the stator teeth 213, thereby providing insulation for the stator winding 210. Winding slots 215 are formed between adjacent stator teeth 213. This allows the stator winding 210 of each stator assembly 21 to be easily wound onto the corresponding stator tooth 213 of the stator assembly 21, simplifying the winding process and significantly improving the slot fill factor of the winding slots 215 of the stator 20. Simultaneously, it also enables the miniaturization of the stator 20 and the motor 100 as a whole. Calculations show that after several stator assemblies 21 are circumferentially joined to form the stator core, and the winding slots 215 accommodate the stator windings 210, the slot fill factor of the winding slots 215 reaches 85%. A higher slot fill factor increases the motor's power density, thereby increasing the maximum output power of the motor 100. The highest slot fill factor of existing motor stator winding slots is only 65%.

[0021] The motor 100 provided in this embodiment is a brushless motor. The motor control module generates a rotating magnetic field by controlling the current direction of each stator winding 210, which drives the rotor 30 to rotate. The driving method of the brushless motor is prior art and will not be described in detail here.

[0022] Please see Figure 4 , Figure 5 and Figure 6 In this embodiment, the circumferential ends of the stator yoke 214 of each stator assembly 21 are used to splice and enclose the stator yoke 214 of the adjacent stator assembly 21, so that the spliced ​​and enclosed stator yoke 214 forms the cylindrical outer wall of the stator core; at the same time, the inner ends of the stator teeth 213 are spliced ​​and enclosed to form the stator central through hole 25. The housing 10 encloses the cylindrical outer wall of the stator core, and the two ends of the housing 10 are respectively fixedly connected to the front end cover 40 and the rear end cover 50. The rotor 30 passes through the stator central through hole 25 and is rotatable relative to the stator 20, the front end cover 40, and the rear end cover 50. Please refer to Figure 5 , Figure 6 and Figure 7Preferably, the stator winding frame block 212 is an insulating film layer that is overlaid onto the outer wall of the stator core block 211. The slot insulation thickness of the insulating film layer ranges from 0.2mm to 0.3mm. Compared with existing stator winding frames, it has a thinner slot insulation thickness, which can increase the effective slot space of the winding slot 215, thereby accommodating a stator winding 210 with more turns of coil, and thus improving the power density of the motor.

[0023] Please see Figure 8 and Figure 9 Specifically, the stator yoke 214 has a connecting protrusion 214a and a connecting recess 214b on both sides. The connecting protrusion 214a of the stator yoke 214 of each stator block 21 engages with the connecting recess 214b of the adjacent stator block 21, so that several stator blocks 21 are fixedly connected and enclosed to form the whole of the stator 20.

[0024] Please see Figure 10 and Figure 11 In this embodiment, the rotor 30 includes a rotor core 31, a magnetic assembly 32, and a central shaft 33. The rotor core 31 has a hollow hole, and the central shaft 33 passes through this hollow hole and is fixed to the rotor core 31; for example, the central shaft 33 is tightly fitted into the hollow hole. Specifically, the axis of the central shaft 33 is collinear with the axial centerline of the rotor core 31.

[0025] Preferably, the magnetic component 32 is embedded inside the rotor core 31. This embedded rotor magnet structure is more reliable when the motor 100 is running at high speed; it also makes the motor 100 more compact overall.

[0026] Please see Figure 2 and Figure 11 In this embodiment, the stator core is assembled from nine stator blocks 21, and has nine stator teeth 213 and nine stator windings 210. Each stator winding 210 is wound around one stator tooth 213, and nine winding slots 215 are formed between the nine stator teeth. The rotor 30 forms a total of six magnetic poles, which are evenly distributed along the circumference of the rotor 30. This structure of nine winding slots 215 and six magnetic poles can reduce the cogging torque of the motor 100, as well as reduce the operating noise and vibration amplitude of the motor 100. Understandably, in a specific embodiment, the magnetic component 32 of the rotor 30 has six magnetic elements 321, and the first magnetic element 321 forms one magnetic pole of the rotor 30.

[0027] Please see Figure 10Preferably, the rotor core 31 adopts a segmented, staggered pole structure. In this embodiment, the rotor core 31 includes a first axial segment 311 and a second axial segment 312 along the axial direction, and the magnetic poles of the first axial segment 311 and the magnetic poles of the second axial segment 312 are offset in the circumferential direction. In a preferred embodiment, the angle of circumferential offset between the magnetic poles of the first axial segment 311 and the magnetic poles of the second axial segment 312 is 10 degrees. This can further reduce the cogging torque and torque pulsation of the motor, as well as reduce the operating noise and vibration amplitude of the motor 100, making the motor 100 operate more smoothly.

[0028] Please see Figure 3 and Figure 10 In this embodiment, the motor 100 further includes a first bearing 35 and a second bearing 36 respectively disposed between the two ends of the central shaft 33 and the front end cover 40 and the rear end cover 50. The first bearing 35 and the second bearing 36 cause the central shaft 33 to drive the rotor 30 to rotate relative to the stator 20, the front end cover 40 and the rear end cover 50.

[0029] Further, please refer to Figure 3 The motor 100 also includes a rotor balancer 37 and an adjusting shim 38 disposed at the junction of the central shaft 33 and the two ends of the rotor core 31. At least one end of the rotor core 31 is provided with the rotor balancer 37 and the other end is provided with the adjusting shim 38 to ensure that the rotor 30 runs smoothly and to keep the two ends of the central shaft 33 able to rotate smoothly relative to the front end cover 40 and the rear end cover 50.

[0030] Please see Figure 2 , Figure 3 , Figure 10 and Figure 11 It should be noted that the stator block structure and the rotor structure with embedded rotor magnets of this invention enable the miniaturization of the entire motor. Simultaneously, the aforementioned 9-slot, 6-pole slot-pole matching structure and rotor segmented staggered-pole structure reduce noise and vibration generated during motor operation. As a drive motor for an electric seat, this invention improves user comfort. The electric seat includes a seat body and a drive motor for adjusting the movement of the seat body. For example, this invention is applicable to automobile seats, enabling smooth height and horizontal movement adjustments of the seat body and providing a pleasant user experience.

[0031] Example 2 This embodiment also provides a method for manufacturing an electric motor, for manufacturing the electric motor 100 of the above embodiment 1.

[0032] Please see Figure 12 The method for manufacturing the motor includes the following steps: S1. Preparation of stator assembly 21: A stator wire frame block 212 is overmolded onto the surface of a stator core block 211, and the stator wire frame block 212 covers the stator teeth 213 of the stator core block 211. Then, a stator winding 210 is wound onto the stator teeth 213, thus obtaining a stator assembly 21. In this way, the stator winding 210 of each stator assembly 21 can be easily wound onto the stator teeth 213 of its corresponding stator assembly 21, making the winding process simpler. While controlling the overall miniaturization of the product, it can also significantly improve the slot fill factor of the winding slots 215 of the stator 20 and increase the power density of the motor, thereby increasing the maximum output power of the motor 100.

[0033] Several stator modules 21 are prepared according to the steps described above for preparing one stator module 21.

[0034] S2, Enclosed splicing: The circumferential ends of the stator yoke 214 or stator tooth 213 of a stator assembly 21 are spliced ​​with the stator yoke 214 or stator tooth 213 of the adjacent stator assembly 21; several stator assemblies 21 are spliced ​​together to form a stator core with several winding grooves 215; and the inner ends of several stator teeth 213 are spliced ​​together to form a stator center through hole 25, and several stator yokes 214 are spliced ​​together to form a cylindrical outer wall of the stator core; thus, the stator 20 as a whole is prepared.

[0035] Specifically, step S2 further includes: providing connecting protrusions 214a and connecting recesses 214b on both sides of the stator yoke 214; engaging the connecting protrusions 214a and connecting recesses 214b of adjacent stator blocks 21 with each other; thereby achieving the assembly and fixed connection between the stator yokes 214 of adjacent stator blocks 21. In this way, several stator blocks 21 are fixedly connected and enclosed to form the stator 20 as a whole. Preferably, welding is performed at the connection points of adjacent connecting protrusions 214a and connecting recesses 214b to further strengthen the fixed connection between adjacent stator blocks 21; thus forming a more robustly connected stator 20.

[0036] S3, Assembly Housing 10: The housing 10 is fitted into the stator core, so that the housing 10 covers the cylindrical outer wall of the stator core.

[0037] S4. Assemble rotor 30 and install end cover: Pass the rotor 30 through the central through hole 25 of the stator; The front cover 40 and the rear cover 50 are fixed to the two ends of the housing 10 respectively; and the rotor 30 is rotatable relative to the stator 20, the front cover 40 and the rear cover 50.

[0038] The above embodiments only illustrate preferred embodiments of the present invention, and their descriptions are relatively specific and detailed, but they should not be construed as limiting the scope of the present invention. It should be noted that those skilled in the art can make several modifications and improvements without departing from the concept of the present invention, such as combining different features in various embodiments, and these all fall within the protection scope of the present invention.

Claims

1. An electric motor, comprising a housing (10), a stator (20), a rotor (30), a front end cover (40), and a rear end cover (50), characterized in that, The stator (20) includes a stator core and a stator winding (210), wherein the stator core is formed by splicing together several stator blocks (21) in the circumferential direction; Each stator module (21) includes a stator core block (211), a stator wire frame block (212), and a stator winding (210). The stator wire frame block (212) is overmolded onto the surface of the stator core block (211) to provide insulation to the stator winding (210). The stator core block (211), the stator wire frame block (212), and the corresponding stator winding (210) form a whole of the stator module (21). Each stator core block (211) includes an arc-shaped stator yoke (214) and stator teeth (213) extending inward from the stator yoke (214), the stator teeth (213) being wound with one stator winding (210); the circumferential ends of the stator yoke (214) of each stator block (21) are used to splice and enclose with the stator yoke (214) of the adjacent stator block (21), so that the splicing and enclosing of the stator yoke (214) forms the cylindrical outer wall of the stator core, and the splicing and enclosing of the inner ends of the stator teeth (213) forms the stator center through hole (25); a winding groove (215) is formed between adjacent stator teeth (213). The housing (10) encloses the cylindrical outer wall of the stator core, and the two ends of the housing (10) are respectively fixedly connected to the front end cover (40) and the rear end cover (50). The rotor (30) passes through the central through hole (25) of the stator and is rotatable relative to the stator (20), the front end cover (40) and the rear end cover (50).

2. The motor according to claim 1, characterized in that, After the stator core is formed by splicing and enclosing the stator blocks (21) in the circumferential direction, the winding slot (215) accommodates the stator winding and the slot fill factor of the winding slot (215) reaches 85%.

3. The motor according to claim 1, characterized in that, The stator wire frame block (212) is an insulating film layer that is formed over the outer wall of the stator core block (211), and the thickness of the slot insulating film layer of the stator wire frame block (212) ranges from 0.2mm to 0.3mm.

4. The motor according to claim 1, characterized in that, The rotor (30) includes a rotor core (31), a magnetic component (32), and a central shaft (33). The magnetic component (32) is embedded inside the rotor core (31). The rotor core (31) has a hollow hole, and the central shaft (33) passes through the hollow hole and is fixed to the rotor core (31). The axis of the central shaft (33) is collinear with the axial centerline of the rotor core (31).

5. The motor according to claim 4, characterized in that, The rotor core (31) includes a first axial segment (311) and a second axial segment (312) along the axial direction. The magnetic poles of the first axial segment (311) and the magnetic poles of the second axial segment (312) are offset in the circumferential direction.

6. The motor according to claim 4, characterized in that, The stator core is assembled from 9 stator blocks (21) and has 9 stator teeth (213) and 9 stator windings (210). Each stator winding (210) is wound around one stator tooth (213), and 9 winding slots (215) are formed between the 9 stator teeth (213). The rotor (30) has a total of 6 magnetic poles, which are evenly distributed along the circumference of the rotor (30).

7. The motor according to claim 4, characterized in that, It also includes a rotor balancer (37) and an adjusting shim (38) disposed at the junction of the central shaft (33) and the two ends of the rotor core (31); at least one end of the rotor core (31) is provided with the rotor balancer (37), and the other end is provided with the adjusting shim (38).

8. The motor according to claim 1, characterized in that, The stator yoke (214) is provided with a connecting protrusion (214a) and a connecting recess (214b) on both sides respectively. The connecting protrusion (214a) of the stator yoke (214) of each stator block (21) is engaged with the connecting recess (214b) of the adjacent stator block (21), so that several stator blocks (21) are fixedly connected and enclosed to form the whole of the stator (20).

9. A method for manufacturing an electric motor, used to manufacture the electric motor of claim 1, characterized in that, Includes the following steps: S1. Preparation of stator assembly (21): A stator wire frame block (212) is overmolded onto the surface of a stator core block (211), and the stator wire frame block (212) is overmolded onto the stator teeth (213) of the stator core block (211); then a stator winding (210) is wound onto the stator teeth (213) to obtain a stator assembly block (21). Several stator modules (21) are prepared according to the above steps for preparing one stator module (21); S2, Enclosed splicing: The circumferential ends of the stator yoke (214) or stator tooth (213) of a stator assembly (21) are spliced ​​with the stator yoke (214) or stator tooth (213) of the adjacent stator assembly (21); several stator assemblies (21) are spliced ​​together to form a stator core with several winding slots (215); and the inner ends of several stator teeth (213) are spliced ​​together to form a stator center through hole (25), and several stator yokes (214) are spliced ​​together to form the cylindrical outer wall of the stator core; thereby obtaining the entire stator (20); the number of winding slots (215) is equal to the number of stator teeth (213); S3, Assemble the casing (10): The housing (10) is fitted into the stator core, so that the housing (10) covers the cylindrical outer wall of the stator core; S4. Assemble the rotor (30) and install the end cover: The rotor (30) is passed through the central through hole (25) of the stator; The front cover (40) and the rear cover (50) are fixed to the two ends of the housing (10) respectively; and the rotor (30) is rotatable relative to the stator (20), the front cover (40) and the rear cover (50).

10. The method for manufacturing an electric motor according to claim 9, characterized in that, In S2, a connecting protrusion (214a) and a connecting recess (214b) are respectively provided on both sides of the stator yoke (214); the connecting protrusion (214a) and the connecting recess (214b) of the stator yoke (214) of the adjacent stator blocks (21) are engaged, thereby fixing and connecting several stator blocks (21) together to form the stator (20) as a whole; and the connection between the adjacent connecting protrusion (214a) and the connecting recess (214b) is welded.

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