Method for forming a circular shape of a modular motor stator group

Abstract

The present invention relates to a method for circularizing a modular motor stator group, which comprises the following steps: vertically placing the segmented stator core wound with coils on the base of a combined tooling, inserting a split centering pressing plate in contact with the inner hole of the stator core and locking it; supplying power to the windings of the segmented stator core, at this time the stator core with windings is magnetic and is attracted together with the magnetic centering pressing plate; welding or thermally sleeving a housing, a steel sleeve, etc. at the radial splicing position of the outer circle of the segmented core in a complete circle; removing the direct current, at this time the stator core has been spliced into a complete circle with good cylindricity; sequentially removing the bolts, the base and the centering pressing plate. The present invention uses a combined tooling to ensure that the segmented stator always fits with the centering tooling during the assembly and welding process, ensuring the cylindricity of the stator core and at the same time ensuring the important dimension air gap of the motor; when removing the tooling, the tooling does not scratch the inner circle of the stator core, avoiding appearance defects and other impacts on the stator.

Description

Technical Field

[0001] The present invention relates to the technical field of motor stators, and particularly relates to a method for assembling a split-type motor stator into a circle. Background Art

[0002] The cost of traditional integral stator core stamping dies is high and there is a lot of stamping blanking. To reduce cogging torque and increase torque, most stator cores are semi-open slots, resulting in difficulty in improving the slot filling rate of the winding slot. The split-type stator core divides the integral stator core into several stator blocks according to the number of stator slots of the stator core, and then assembles them into a complete circular structure stator. This core structure can effectively solve the problems of stamping die cost and waste of raw materials, and directly wind the wire on the segmented core, which can greatly reduce the height of the winding end and improve the slot filling rate. Therefore, split-type stator cores are gradually popularized in the market, especially for motor solutions with a large outer diameter and a short axial length, which generally adopt split-type stator cores.

[0003] In actual production of split-type stator cores, when the split blocks are combined into a complete circle, due to reasons such as uneven force on the segmented stator cores, it is impossible to ensure the cylindricity of the core, resulting in uneven air gap of the motor, increased cogging torque and torque ripple of the permanent magnet motor, and a series of NVH problems such as unilateral magnetic pull force may also occur during operation. Summary of the Invention

[0004] The purpose of the present invention is to provide a method for assembling a split-type motor stator into a circle in response to the deficiencies of the prior art, which ensures the cylindricity of the inner hole of the stator core and avoids NVH problems such as torque ripple caused by uneven air gap of the motor.

[0005] The purpose of the present invention is achieved by the following solution: A method for assembling a split-type motor stator into a circle includes the following steps:

[0006] 1) Fix and connect insulating skeletons to both sides of the segmented stator core respectively, and then wind coils on the insulating skeletons to form windings;

[0007] 2) Vertically place all the segmented stator cores with wound coils into the installation slots on the base of the combined tooling, maintaining the electrical safety gap between the base and the windings on each stator core, and at the same time ensuring that the winding ends do not interfere with the base. After all the segmented stator cores are installed, insert positioning keys to form radial positioning;

[0008] 3) Insert multiple stator pressing plates of the combined tooling between the base and the inner holes of each stator core. The inner wall of the stator pressing plate fits with the circumferential surface of the central column of the base, and fixedly connect the upper end surface of the stator pressing plate to the upper end surface of the central column of the base through bolts;

[0009] 4) Connect the two wire ends of the coil windings on each segmented stator core to the positive and negative poles of the DC power supply respectively. The DC power supply supplies power to the segmented stator cores. At this time, each stator core has magnetism, and the magnetic field direction is radial. Each stator core is attracted to the magnetic-conductive stator pressing plate, and the magnitude of the magnetic force can be changed by adjusting the magnitude of the current;

[0010] 5) The magnetic force makes the inner wall of each stator core fit perfectly with the outer wall of the stator pressing plate, and then weld or thermally sleeve the housing, steel sleeve, etc. at the radial splicing position of the outer circle of all segmented cores;

[0011] 6) Disconnect the DC power supply. At this time, each stator core has been spliced into a complete circle with good cylindricity;

[0012] 7) Disconnect the connection of the winding wire ends, remove the bolts, change the fixed connection between the base and the stator pressing plate to be detachable, remove the base, and finally close the multi-piece stator pressing plates towards the middle and take them out.

[0013] Preferably, the combined tooling includes a base, a stator pressing plate, and a positioning key. The center of the base is provided with a trapezoidal center column extending upward. The upper end surface of the center column is provided with a plurality of threaded holes. An installation groove is provided between the lower end of the center column and the base. A positioning groove is provided on the outer circumferential surface of the base, and a positioning key is provided in the positioning groove. The stator pressing plate is composed of multiple pieces spliced together. The inner wall of each stator pressing plate fits with the circumferential surface of the center column of the base. Through holes corresponding to the threaded holes on the upper end surface of the center column are provided on the upper end surface of the stator pressing plate.

[0014] Preferably, the stator pressing plate is provided with three pieces. The stator pressing plate is made of a magnetic-conductive material, and the outer diameter of the stator pressing plate is the same as the inner hole diameter of the stator core.

[0015] Preferably, the stator pressing plate and the base can be assembled and disassembled.

[0016] Preferably, the outer diameter of the insulating skeleton is smaller than the inner diameter of the installation groove of the base.

[0017] Preferably, the outer diameter of the stator core is smaller than the outer diameter of the base.

[0018] Preferably, the inner diameter of the upper end of the stator pressing plate is the same as the diameter of the upper end surface of the center column, and the inner diameter of the lower end of the stator pressing plate is the same as the diameter of the lower end surface of the center column.

[0019] Compared with the prior art, the present invention has the following beneficial effects:

[0020] 1. Ensure the cylindricity of the inner hole of the stator core, and avoid NVH problems such as torque ripple caused by uneven air gap of the motor;

[0021] 2. The stator core and the centering pressing plate are attached by magnetic force, and the magnitude of the magnetic force can be adjusted by adjusting the magnitude of the current;

[0022] 3. The combined tooling has low cost, is easy to operate, install and disassemble, is not prone to abrasion with the inner circle of the stator, and has high installation efficiency. Description of the Drawings

[0023] Figure 1 It is a schematic structural diagram of the present invention;

[0024] Figure 2 It is a sectional view of the present invention;

[0025] Figure 3 It is a schematic structural diagram of the base of the present invention;

[0026] Figure 4 It is a schematic structural diagram of the centering pressure plate of the present invention;

[0027] Figure 5 It is a schematic structural diagram of a single stator core with an insulating skeleton and a winding of the present invention. Detailed Embodiment

[0028] As Figures 1 to 5 shown, a method for assembling a segmented motor stator into a circle includes the following steps:

[0029] 1) Fix and connect the insulating skeletons 6 to both sides of the segmented stator core 4 respectively, and then wind coils on the insulating skeletons 6 to form windings 5;

[0030] 2) Vertically place all the segmented stator cores 4 wound with coils into the installation grooves 1-5 of the base 1 of the combined tooling, maintaining the electrical safety gap between the base 1 and the windings 5 on each stator core 4, and at the same time ensuring that the ends of the windings 5 do not interfere with the base 1. After all the segmented stator cores 4 are installed, insert the positioning keys 3 to form radial positioning;

[0031] 3) Insert multiple stator pressure plates 2 of the combined tooling between the base 1 and the inner holes of each stator core 4. The inner wall of the stator pressure plate 2 fits against the circumferential surface of the central column 1-3 of the base, and fixedly connect the upper end surface of the stator pressure plate 2 to the upper end surface of the central column 1-3 of the base through bolts 7;

[0032] 4) Connect the two wire ends of the coil windings 5 on each segmented stator core 4, the first wire end 5-1 and the second wire end 5-2, to the positive and negative poles of the DC power supply respectively. The DC power supply supplies power to the segmented stator core 4. At this time, each stator core has magnetism, and the magnetic field direction is radial. Each stator core 4 is attracted to the magnetic-conductive stator pressure plate 2, and the magnitude of the magnetic force can be changed by adjusting the magnitude of the current;

[0033] 5) The magnetic force makes the inner wall of each stator core 4 fit perfectly with the outer wall of the stator pressing plate 2, and then welds or heat-sheaths a housing, a steel sleeve, etc. at the radially spliced positions of the outer circles of all the segmented cores 4;

[0034] 6) Disconnect the DC power supply. At this time, each stator core 4 has been spliced into a complete circle with good cylindricity;

[0035] 7) Disconnect the connection of the winding leads, remove the bolts, make the fixed connection between the base 1 and the stator pressing plate 2 detachable, remove the base 1, and finally close the multiple stator pressing plates 2 towards the middle and take them out.

[0036] The combined tooling includes a base 1, a stator pressing plate 2, and a positioning key 3. A trapezoidal central column 1-3 extending upward is provided at the center of the base. A plurality of threaded holes 1-1 are provided on the upper end surface of the central column. An installation groove 1-5 is provided between the lower end of the central column and the base. A positioning groove 1-2 is provided on the outer circumferential surface of the base 1, and a positioning key 3 is provided in the positioning groove. The stator pressing plate 2 is composed of multiple segments spliced together. The inner wall of each stator pressing plate fits with the circumferential surface of the central column 1-3 of the base. Through holes 2-1 corresponding to the threaded holes 1-1 on the upper end surface of the central column are provided on the upper end surface of the stator pressing plate 2. The stator pressing plate is provided with three pieces, and the stator pressing plate is made of a magnetic conductive material. The outer diameter of the stator pressing plate is the same as the inner hole diameter of the stator core. The stator pressing plate and the base can be assembled and disassembled. The outer diameter of the insulating skeleton 6 is smaller than the inner diameter of the base installation groove 1-5. The outer diameter of the stator core is smaller than the outer diameter of the base. The inner diameter of the upper end of the stator pressing plate is the same as the diameter of the upper end surface of the central column, and the inner diameter of the lower end of the stator pressing plate is the same as the diameter of the lower end surface of the central column.

[0037] Among them, the height between the bottom of the stator pressing plate and the bottom of the base installation groove needs to be greater than zero, and the height of the base installation groove minus the height of the end of the insulating skeleton is greater than zero.

[0038] When the steel sleeve interference fit scheme is adopted, there is no need to set the positioning key 3, the base positioning groove 1-2, the core positioning groove 4-1, and the groove 1-4.

[0039] The above are only the preferred embodiments of the present invention and are not used to limit the present invention. Those skilled in the art, without departing from the spirit of the present invention, the modifications made to the present invention all fall within the protection scope of the present invention.

Claims

1. A method for circularizing a modular motor stator group, characterized in that, The steps include the following: 1) Fix and connect the insulating skeletons to both sides of the segmented stator core respectively, and then wind coils on the insulating skeletons to form windings; 2) Vertically place all the segmented stator cores with wound coils into the installation grooves on the base of the combined tooling, maintaining the electrical safety clearance between the base and the windings on each stator core, and at the same time ensuring that the winding ends do not interfere with the base. After all the segmented stator cores are installed, insert the positioning keys to form radial positioning; 3) Insert multiple stator pressing plates of the combined tooling between the base and the inner holes of each segmented stator core. The inner wall of the stator pressing plate fits with the circumferential surface of the central column of the base, and fixedly connect the upper end surface of the stator pressing plate to the upper end surface of the central column of the base through bolts; 4) Connect the two wire ends of the coil windings on each segmented stator core to the positive and negative poles of the DC power supply respectively. The DC power supply supplies power to the segmented stator core. At this time, each stator core has magnetism, and the magnetic field direction is radial. Each stator core is attracted to the magnetic-conductive stator pressing plate, and the magnitude of the magnetic force can be changed by adjusting the magnitude of the current; 5) The magnetic force makes the inner wall of each stator core fit completely with the outer wall of the stator pressing plate, and then weld or thermally sleeve the housing and steel sleeve at the radial splicing positions of the outer circles of all the segmented cores; 6) Disconnect the DC power supply. At this time, each stator core has been spliced into a complete circle with good cylindricity; 7) Disconnect the connection of the winding wire ends, remove the bolts, make the fixed connection between the base and the stator pressing plate detachable, remove the base, and finally close the multiple stator pressing plates towards the middle and take them out.

2. The method for circularizing the modular motor stator group according to claim 1, wherein: The combined tooling includes a base, stator pressing plates, and positioning keys. The center of the base is provided with a trapezoidal central column extending upward. The upper end surface of the central column is provided with a plurality of threaded holes. An installation groove is provided between the lower end of the central column and the base. A positioning groove is provided on the outer circumferential surface of the base, and a positioning key is provided in the positioning groove. The stator pressing plates are composed of multiple pieces spliced together. The inner wall of each stator pressing plate fits with the circumferential surface of the central column of the base. Through holes corresponding to the threaded holes on the upper end surface of the central column are provided on the upper end surface of the stator pressing plate.

3. The method for circularizing the modular motor stator group according to claim 2, characterized in that: The fixed Three stator pressing plates are provided. The stator pressing plates are made of magnetic-conductive materials, and the outer diameter of the stator pressing plate is the same as the inner diameter of the stator core.

4. The method for circularizing the modular motor stator group according to claim 2, wherein: The stator pressing plate and the base can be assembled and disassembled.

5. The method for circularizing the modular motor stator group according to claim 2, characterized in that: The outer diameter of the insulating skeleton is smaller than the inner diameter of the installation groove of the base.

6. The method for circularizing the modular motor stator group according to claim 2, characterized in that: The outer diameter of the stator core is smaller than the outer diameter of the base.

7. The method for circularizing the modular motor stator group according to claim 2, characterized in that: The inner diameter of the upper end of the stator pressing plate is the same as the diameter of the upper end surface of the central column, and the inner diameter of the lower end of the stator pressing plate is the same as the diameter of the lower end surface of the central column.

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