CN112803644A

CN112803644A - Disk motor and stator coil rolling manufacturing method

Info

Publication number: CN112803644A
Application number: CN202110196374.5A
Authority: CN
Inventors: 崔晓宏; 王晓远
Original assignee: Suzhou Noahs Electric Bicycles Co ltd
Current assignee: Suzhou Noahs Electric Bicycles Co ltd
Priority date: 2021-02-22
Filing date: 2021-02-22
Publication date: 2021-05-14
Anticipated expiration: 2041-02-22
Also published as: CN112803644B

Abstract

The invention discloses a disk motor and a stator coil calendering manufacturing method. Gradually thinning at the position of the acting edge of the coil close to the outer diameter; in the area of the working edge of the coil close to the inner diameter, each single working edge of the coil is in a sector shape. The cross section area of the end part edge of the armature coil is larger than that of the working edge by adopting a redundancy design process, the space redundancy of the end part edge of the armature coil is fully utilized, and the resistance is reduced by adopting an enameled wire with a large wire diameter in an over-specification mode, so that the resistance of the armature coil can be greatly reduced, and the efficiency of the motor is improved. The edge of the outer end part is exposed outside beyond the shell, and the heat is dissipated by utilizing the air outside the motor.

Description

Disk motor and stator coil rolling manufacturing method

Technical Field

The invention relates to a permanent magnet disc type motor, in particular to a permanent magnet disc type motor coreless armature and an installation method thereof.

Background

The disc type motor is short in axial size, compact in structure and pancake-shaped in appearance and mainly comprises a stator and a rotor. The stator of the brushless motor is an armature disk, and the rotor is composed of an iron yoke disk and a permanent magnet.

The permanent magnet disc type motor has no excitation loss due to the use of permanent magnet materials, the stator has no iron core, so no iron loss exists, and the stator discs and the rotor discs are arranged in parallel, so that the motor efficiency is higher than that of a cylindrical motor. In the prior art, the air gap length space of a permanent magnet disc type motor is limited, because the contradiction of air gap flux density reduction is influenced by increasing the air gap length, and the improvement of the slot filling rate of a motor winding is an effective way for improving the motor efficiency.

The difference between the inner diameter and the outer diameter of the disc type motor is large, so that more windings are idle at the outer diameter, and the winding arrangement space at the inner diameter is tight, so that the space at the end part is tight. The coils are arranged one above the other at the ends, while the conventional motor armature has room in the region of the outer and inner diameter for use.

Taking a motor of 200W and 3000r/min as an example, the motor efficiency is only less than about 80%. The technical problem to be solved urgently is how to improve the efficiency of a motor and reduce the using amount of a lithium battery for a portable mobile equipment motor.

Disclosure of Invention

The effective conductors of the armature winding of the disc type motor are radially distributed in space, so that the more the idle fan-shaped areas of the winding are at the position closer to the outer diameter, the more the space inside and outside the permanent magnet ring is available. The stator without iron core structure is made up by encapsulating coil in insulating material, pressing into disk shape and making into stator winding disk without iron core.

The technical scheme adopted by the invention is as follows:

the invention aims to provide a calendering preparation method of a high-power-density disc type motor winding coil structure, which aims to solve the technical problem of space saving and reduce armature resistance.

The invention adopts round copper wires and enameled wires for winding, has low cost, selects the enameled wires with super large wire diameter, and rolls, thins and lengthens the enameled wires for a plurality of times on the acting side, namely the effective side, of the coil, so that the enameled wires can be matched with the sectional area of the air gap length space armature: for example, firstly, at the position where the acting edge of the coil is close to the outer diameter of the permanent magnet, more idle areas of the winding coil are formed, and the winding coil becomes thinner gradually in the axial direction of the motor; and secondly, in the area of the working edge of the coil close to the inner diameter of the permanent magnet, the radial side surface of the motor is gradually thinned. Each single conductor of the coil working edge presents a sector shape when viewed in a plane; the working edge of the coil is in an inverted sector shape when viewed from the side. Namely, the air gap at the outer diameter of the permanent magnet is short, and the air gap at the inner diameter of the permanent magnet is long.

Further, the air gap at the inner diameter of the permanent magnet is increased to a slightly shorter value than the theoretical value, which advantageously increases the magnetic density at the inner diameter, i.e. the cross-sectional area of the air gap conductor at the inner diameter is deliberately slightly smaller than the cross-sectional area at the outer diameter of the permanent magnet.

The sectional area of the end part of the coil is larger than that of the working side, and each conductor in the area from the inner circle of the permanent magnet to the central circle is extruded to be deformed in a self-adaptive manner and fill the section of the groove. The slot cross section refers to the cross section of the working edge of the armature plate, and the full slot refers to the enameled thickness of the enameled wire plus a lead.

The sectional areas of the end edges of the inner ring and the outer ring of the coil are larger than the sectional area of the conductor at the outer circle of the permanent magnet, and the sectional area of the conductor at the outer circle of the permanent magnet is larger than the sectional area of the conductor at the inner circle of the permanent magnet.

According to the winding and calendering preparation method, the redundancy design process is adopted, the sectional area of the end part edge of the armature coil is larger than that of the acting edge, the space redundancy of the end part edge of the armature coil is fully utilized, the enameled wire with a large wire diameter in an over-specification mode is adopted for processing and winding, the wire diameter is actually enlarged, and therefore the resistance of the armature coil can be greatly reduced, and the efficiency of the motor is improved.

The inner end side stator winding is stacked by each phase winding, such as A, B, C. The three-phase acting edges are uniformly distributed on a plane to reduce the thickness of a magnetic field area and shorten the length of an air gap.

The outer end edge is exposed outside through the stator sleeve shell, and heat is dissipated by using air outside the motor.

One end of the stator sleeve is processed into teeth which are uniformly distributed around the circumference. The tooth gaps are left for the winding conductors to pass through. Presenting a comb-toothed skeleton. Each conductor of the coil is clamped by the comb teeth, so that stable framework support is provided for the armature, and the heat of each conductor is dissipated by utilizing the stator sleeve (9) of the comb teeth.

Furthermore, each winding conductor is extended straight and extended to pass through the outer circle of the stator sleeve and is connected outside the shell. The welding, series connection and parallel connection processes of the conductors outside the shell are simple, the operation is easy, the production cost is reduced, and the controller is convenient to electrically connect. The flexible application of the series-parallel connection of the conductors can freely adjust the rotating speed and the power of the motor.

Furthermore, the outer end edge of the armature coil is sealed on the stator sleeve and is fixedly connected with the bearing inner ring through the shell.

The enameled wire is wound into a coil unit and then is subjected to rolling treatment while doing work, so that the groove fullness rate is higher, the air gap is smooth, the space utilization rate of the inner diameter and the outer diameter is higher, and the enameled wire is very beneficial to design and processing of a high-power-density motor.

In the area from the inner circle line of the permanent magnet to the center circle line of the permanent magnet, the full rate of the conductor groove is in a full groove state, namely, the conductor is pressed into a rectangle or a square shape, the thickness of the insulating layer is less than 0.1mm, and each conductor is not in clearance proximity with each other.

Furthermore, at least in the area from the inner circle to the central circle of the permanent magnet, each conductor is not closely attached to each other in a gap mode, rolling is adopted, each conductor is made to be rectangular through extrusion, and the full rate of the conductor groove is in a full groove state. And each conductor is self-adaptively deformed by adopting extrusion to fill the groove. Each conductor in at least the region from the inner circle to the central circle of the permanent magnet is extruded to be self-adaptively deformed, and the cross section of the groove is filled. A full slot does not mean an absolute full slot and there may be only remaining process corners, four corners of a square or rectangle, such as rounded corners where R <0.2 or so.

The motor iron-core-free and skeleton-free structure realizes the skeleton type of the stator in the excircle area on the basis, is used for heat conduction and radiation and anti-rotation torque, and accurately fixes a circle of petal-shaped coils in a flat plane, so that the structure is firmer.

The disc type coreless motor generates torque mainly in a region from an outer circle line to a central circle line of a permanent magnet, and a framework for resisting rotation torque is arranged in the region.

The invention introduces the reinforcing sheet at the outer circle of the permanent magnet body, and fills the reinforcing sheet in the narrow gap area at the outer edge of the petal-shaped coil. The reinforcing sheet is a rigid body, such as aluminum alloy, stainless steel, ceramic sheet, powder sintering, thermosetting material, and BMC packaging after mould pressing. And 3D printing technology can be adopted to realize the manufacture of the stator framework.

Taking a motor of 200W and 3000r/min as an example, the motor efficiency can reach more than 90%, and the use amount of a lithium battery can be saved by 10% when the motor is used on mobile equipment.

The coil becomes thinner gradually at the working edge close to the outer diameter, the air gap space is saved, the length of the air gap is shortened, the yoke part at the outer diameter is close to a little, the magnetic flux density of the air gap is increased, and the torque of the motor is improved.

The coil is rolled for multiple times while acting, so that the total number of conductors which can be accommodated in a certain space is increased, and the efficiency is improved.

The coil acting edge realizes the deformation of different shapes of different parts of the coil through the deformation treatment of armature topological geometry or space, so that the coil acting edge is suitable for a disc type motor under a small air gap, the resistance of an armature winding is effectively reduced, and the efficiency of the motor is improved.

The invention improves the space utilization rate of the winding, and simultaneously increases the limit driving current of the disc type motor, improves the torque characteristic and the power density and the like on the premise of ensuring the reasonable temperature rise characteristic.

According to the invention, the round copper wire calendering preparation method is adopted, so that the work-applying edge conductor is more compact in crystallization and becomes hard; the crystal orientation becomes longer in the current direction, and the resistance decreases. The conductor hardening is favorable for the armature plate of the stator to improve rigidity, resist deformation and ensure flatness.

The invention is further described with reference to the following figures and detailed description:

FIG. 1 is a partial schematic view of an armature phase A coil unit according to an embodiment of the present invention;

FIG. 2 is a cross-sectional view of an armature coil and a schematic illustration of a reinforcing patch according to an embodiment of the present invention;

fig. 3 is a sectional view of a disc motor according to an embodiment of the present invention;

FIG. 4 is a schematic cross-sectional view of a conductor at the inner and outer circles of an armature according to an embodiment of the present invention;

FIG. 5 is a A, B phase schematic diagram of an armature three phase winding according to an embodiment of the present invention;

FIG. 6 is a schematic view of an A, B, C phase coil according to an embodiment of the present invention;

in the figure: 1. a coil; 2. doing work; 3. an end edge; 4. a permanent magnet; 5. an inner circle; 6. a central circle; 7. an outer circle; 8. a housing; 9. a stator sleeve; 10. a reinforcing sheet; 51. the section of the conductor at the inner circle; 71. the section of the conductor at the excircle.

As shown in figure 1, the invention adopts a round copper wire or a square or rectangular enameled wire to wind, and preferably adopts a round enameled copper wire in a wave winding mode according to the principle of lowest cost. Take a single-layer armature winding as an example: the armature coils (1) are arranged in a staggered two-layer mode at the end part of the inner circle, and are arranged in a single layer mode while acting; as shown in fig. 2 and 4, a two-layer wire armature winding is taken as an example: the armature coils (1) are arranged in four layers in a staggered mode at the end portion of the inner circle, and are arranged in two layers while acting.

Furthermore, the coil (1) is rolled in multiple directions for multiple times, which includes the processes of rolling by a roller, punching by a die, extruding by the die and the like, so that the sectional area of the end part of the armature is larger than that of the working edge by 1.5 times. As shown in fig. 3, the air gap length becomes shorter near the outer circle (7). The conductor of the working edge (2) is close to the excircle (7) and changes; the body becomes narrower and thicker near the inner circle (5).

The sectional area of the end part of the armature is larger than that of the working edge, and each conductor in the area from the inner circle of the permanent magnet to the central circle is extruded to be deformed in a self-adaptive manner and fill the section of the slot.

Furthermore, each conductor at least in the area from the inner circle to the central circle of the permanent magnet is extruded to be deformed in a self-adaptive mode, and the method comprises a method for achieving the processes of cutting, stamping and shaping the sheet materials before winding.

As shown in figure 2, the stator armature disk is clamped in the middle of a rotor disk formed by permanent magnets, space below the permanent magnets, namely space in a coil, is redundant, and the end edges at the inner ends of the coils (1) are stacked in multiple phases.

As shown in FIGS. 3 and 4, the conductor coil corresponding to the permanent magnet of the present invention is formed by rolling to have a cross section (51) at the inner circle and a cross section (71) at the outer circle.

As shown in fig. 1 and 5, the stator sleeve (9) is close to the coil (1) and is in a comb tooth shape, and surrounds a ring of teeth. The whole ring body on the right side of the stator sleeve (9) is fixed with the shell (8). Each conductor of the coil (1) is clamped by the comb teeth, so that stable framework support is provided for the armature, and the heat of each conductor is dissipated by the stator sleeve (9) of the comb teeth. The stator sleeve (9) is made of aluminum alloy, and the heat dissipation performance is better.

As shown in fig. 2 and 3, further, the outer end edge of each conductor of the coil (1) is exposed outside beyond the stator sleeve (9), and each conductor extends straight and extends out to pass through the stator sleeve (9) and is connected outside the shell, such as welding, series connection and parallel connection.

The disk type motor and the stator coil calendering manufacturing method comprise a coil (1) and a stator sleeve (9), and are characterized in that the outer end edge of the armature coil (1) is sealed on the outer ring of the stator sleeve (9) and is fixedly connected with the inner ring of a bearing through a shell (8).

As shown in fig. 1 and 2, a plurality of reinforcing sheets (10) are clamped by the armature coil unit gaps, are uniformly distributed around the armature coil unit gaps, have extremely thin thickness and can be controlled below the thickness of only 0.2 mm; can be controlled below the thickness of only 0.1 mm.

Fig. 5 is a schematic diagram of an armature with one phase removed, and 6 pairs of poles are used as an example, and reinforcing plates (10) are introduced into the mutual gaps of 18 winding units of three phases, and the number of the reinforcing plates is 36. The number of slices introduced is the number of pole pairs multiplied by the number of phases multiplied by 2.

Furthermore, the reinforcing sheet (10) is a rigid body, such as aluminum alloy, stainless steel, ceramic sheet, powder sintering and thermosetting material, and is packaged by BMC after mould pressing, and 3D printing technology can also be adopted. The reinforcing pieces (10) are vertically and uniformly attached to the outer side of each coil (1) unit conductor and are fixed on the stator sleeve (9) through encapsulation. The inner port of the reinforcing sheet (10) is inserted into the center circle (6) of the permanent magnet (4) to the maximum extent.

As shown in figure 2, the armature coils A, B, C are densely and uniformly distributed, and the working edge (2) at least fills the cross section of each conductor in the area from the inner circle of the permanent magnet to the central circle.

Claims

1. A stator coil rolling manufacturing method is characterized in that: the sectional area of the end part edge (3) of the coil (1) is larger than that of the working edge (2), and at least each conductor in the area from the inner circle of the permanent magnet to the central circle fills the section of the slot.

2. The method of claim 1, wherein: the sectional areas of the end edges (3) of the inner ring and the outer ring of the coil are larger than the sectional area of a conductor at the position of the outer circle (7) of the permanent magnet, and the sectional area of the conductor at the position of the outer circle (7) of the permanent magnet is larger than the sectional area of a conductor at the position of the inner circle (5) of the permanent magnet.

3. The method of claim 1, wherein: the wire diameter is enlarged by utilizing the space redundancy of the end edge (3) of the armature coil.

4. The method of claim 1, wherein: the armature coil (1) is wound by adopting round enameled wires.

5. The method of claim 1, wherein: the armature coil (1) adopts a calendering preparation method to ensure that the crystallization of the working edge conductor is more compact and the conductor is hardened; the crystal is lengthened towards the current direction, the resistance is reduced, and the armature plate is favorable for improving the rigidity and resisting the deformation.

6. A disk motor, includes armature coil (1), stator cover (9), its characterized in that: the stator sleeve (9) is in a comb-tooth shape, the outer end edge (3) of each conductor of the coil (1) is exposed outside beyond the stator sleeve (9), and heat is dissipated by using air outside the motor.

7. The method of claim 6, wherein: and the outer end edge (3) of the coil (1) is encapsulated on the outer ring of the stator sleeve (9) and is fixedly connected with the inner ring of the bearing through the shell (8).

8. The method of claim 6, wherein: the unit gap of the armature coil (1) clamps a reinforcing sheet (10) and is encapsulated on the stator sleeve (9).

9. The method of claim 6, wherein: the inner port of the reinforcing sheet (10) is inserted into the center circle (6) of the permanent magnet (4) to the maximum extent.

10. A disk motor, includes permanent magnet (4), coil (1), stator cover (9), its characterized in that: the rotor composed of the permanent magnet (4) is fixed on the bearing outer ring, and a stator sleeve (9) is clamped between the outer end edge (3) of the armature coil (1) and the acting edge and is fixedly connected with the bearing inner ring through a shell (8).