CN114079361A - Disk type motor - Google Patents

Abstract

The application discloses disc motor includes: an output shaft defining a central axis and defining an axial direction extending along the central axis, a radial direction perpendicular to the axial direction and a circumferential direction around the axial direction; a stator assembly including an inner layer stator coil group and an outer layer stator coil group, the inner and outer layer stator coil groups including a plurality of inner layer stator coils and a plurality of outer layer stator coils, respectively, that are uniformly arranged in a circumferential direction and have an equal first number, each inner layer stator coil having a corresponding outer layer stator coil that is aligned in a radial direction and located radially outward thereof; a rotor assembly including an inner layer magnet set and an outer layer magnet set, the inner and outer layer magnet sets respectively including a plurality of inner layer magnets and a plurality of outer layer magnets uniformly arranged in a circumferential direction and having an equal second number, each inner layer magnet having a corresponding outer layer magnet aligned in a radial direction and located radially outward thereof.

Description

Disk type motor

Technical Field

The present application relates to a disc motor.

Background

An AFPMM (axial flux permanent magnet motor) is attracting more and more attention due to its advantages of compact structure, high efficiency, high power density, and the like. This type of machine is particularly suitable for use in electric vehicles, renewable energy systems and other applications where high torque density and compact construction are required.

Generally, a disc motor includes a stator assembly and a rotor assembly arranged side-by-side about an output shaft and along an axial direction defined by the output shaft. The stator assembly includes a stator coil for generating an axial magnetic field that passes through an axial air gap between the stator and rotor assemblies. The rotor assembly includes a magnet that rotates about the output shaft while cutting the magnetic lines of force of the magnetic field.

In the related-art structure, as shown in fig. 1, in a cross section perpendicular to the axial direction defined by the output shaft, a plurality of stator coils 10 are arranged uniformly in the circumferential direction around the axial direction, each stator coil 10 being formed by a wire wound on a stator core.

The radially inner contour and the radially outer contour of each stator coil 10 constitute an inner circumferential portion and an outer circumferential portion. With the stator structure of this arrangement, the temperature of the inner circumferential portion is higher than that of the outer circumferential portion, and the allowable temperature limit at the inner circumferential portion results in that more wires cannot be wound, thereby limiting the improvement of the power density of the motor.

It is desirable to solve the above-mentioned problems and to improve the power density of the motor.

Disclosure of Invention

The purpose of this application is to provide a new disc motor structure that can improve power density.

To this end, the present application provides a disc motor comprising:

an output shaft defining a central axis and defining an axial direction extending along the central axis, a radial direction perpendicular to the axial direction and a circumferential direction around the axial direction;

a stator assembly mounted around the output shaft and fixed relative to a housing of the disc motor, the stator assembly including an inner set of stator coils and an outer set of stator coils, the inner and outer sets of stator coils including a plurality of inner stator coils and a plurality of outer stator coils, respectively, evenly arranged in a circumferential direction and having an equal first number, each inner stator coil having a corresponding outer stator coil aligned in a radial direction and located on an outer side thereof away from a central axis;

a rotor assembly mounted to the output shaft and rotating therewith, the rotor assembly including an inner magnet set and an outer magnet set, the inner and outer magnet sets respectively including a plurality of inner magnets and a plurality of outer magnets arranged in a circumferential direction and having an equal second number, each inner magnet having a corresponding outer magnet aligned in a radial direction and located on an outer side thereof away from the central axis.

In one embodiment, in a cross section perpendicular to the axial direction, the inner layer stator coil has first and second side edges that are opposite in the circumferential direction, the outer contour of the outer layer stator coil has first and second side edges that are opposite in the circumferential direction, and the first and second side edges of the inner layer stator coil are substantially radially aligned with the first and second side edges of the outer layer stator coil, respectively.

In one embodiment, in a cross section perpendicular to the axial direction, outer contours of the inner-layer stator coil and the outer-layer stator coil have substantially equal angles with respect to a central axis of the output shaft.

In one embodiment, the stator assembly includes a stator housing secured to the disc motor, the stator housing including a plurality of compartments spaced apart in a circumferential direction by a plurality of spacers, each compartment housing one inner stator coil and an outer stator coil radially aligned therewith.

In one embodiment, the inner magnet group includes a plurality of inner magnet subgroups arranged in the circumferential direction and spaced apart from each other, each inner magnet subgroup including a plurality of inner magnets adjoining in the circumferential direction; accordingly, the outer layer magnet group includes a plurality of outer layer magnet subgroups arranged in the circumferential direction and spaced apart from each other, each outer layer magnet subgroup including a plurality of outer layer magnets adjoining in the circumferential direction.

In one embodiment, in a cross-section perpendicular to the axial direction, the outer contour of the inner layer magnet has first and second circumferentially opposite side edges, the outer contour of the outer layer magnet has first and second circumferentially opposite side edges, and the first and second side edges of the inner layer magnet are substantially radially aligned with the first and second side edges of the outer layer magnet, respectively.

In one embodiment, in a cross section perpendicular to the axial direction, the outer contours of the inner magnet and the outer magnet have substantially equal angles with respect to the central axis of the output shaft.

In one embodiment, the inner-layer stator coil and the outer-layer stator coil include an inner-layer core and an outer-layer core, respectively, and the lead wires are wound around lead wire wound portions of the inner-layer core and the outer-layer core, respectively, to form the inner-layer stator coil and the outer-layer stator coil.

In one embodiment, the wire wound portions of the inner core and the outer core have a substantially fan-like or substantially trapezoidal shape in a cross section perpendicular to the axial direction.

In one embodiment, the first number is greater than the second number, preferably the first number is 1.5 times the second number.

In one embodiment, the at least one stator assembly is two stator assemblies and the at least one rotor assembly is one rotor assembly, wherein the one rotor assembly is arranged between the two stator assemblies in the axial direction; or

The at least one stator assembly is one stator assembly and the at least one rotor assembly is two rotor assemblies, wherein the one stator assembly is disposed between the two rotor assemblies in the axial direction; or

The at least one stator assembly includes one stator assembly and the at least one rotor assembly includes one rotor assembly, wherein the one stator assembly and the one rotor assembly are arranged side-by-side in the axial direction.

According to the disc motor of the present application, the stator assembly includes an inner layer stator coil group and an outer layer stator coil group separated from each other in the radial direction, and correspondingly, the rotor assembly includes an inner layer magnet group and an outer layer magnet group separated from each other in the radial direction. Since the outer circumferential portion of the outer stator coil group does not reach the maximum allowable temperature when the inner circumferential portion of the inner stator coil group reaches the limit of the allowable temperature, separately providing the inner stator coil group and the outer stator coil group enables the number of turns of each outer stator coil in the outer stator coil group to be increased independently of its corresponding inner stator coil, thereby improving power density.

Drawings

The foregoing and other features, advantages and benefits of the present application will be described in detail below with reference to the drawings, in conjunction with exemplary embodiments of the present application.

Fig. 1 is a schematic diagram of the arrangement of stator coils constituting a stator assembly of a prior art disc motor;

FIG. 2 illustrates a perspective view of a disc motor including two rotor assemblies and a stator assembly sandwiched therebetween according to the present application;

FIG. 3 is another view of FIG. 2 with one rotor assembly removed to expose the arrangement of stator coils of the stator assembly;

fig. 4 is a front view of fig. 3, in which only the arrangement of stator coils is shown;

FIG. 5 is an enlarged view of a portion of FIG. 4 including an inner layer stator coil and a corresponding outer layer stator coil located radially outwardly thereof;

FIG. 6 is a schematic view of the rotor assembly of the disc motor of FIG. 2 according to the present application;

FIG. 7 is a front view of FIG. 6, showing only the arrangement of the magnets; and

fig. 8 is an enlarged view of a portion of fig. 7 including an inner set of magnets and a corresponding outer set of magnets radially outward thereof.

Detailed Description

The disc motors (or "disc permanent magnet motors" and "axial flux permanent magnet motors") of the present application generally include an output shaft and at least one stator assembly and at least one rotor assembly.

The output shaft of the disc motor defines a central axis or axis of rotation, an axial direction extending along the central axis, a radial direction perpendicular to the axial direction, and a circumferential direction extending around the axial direction. The at least one stator assembly and the at least one rotor assembly are mounted around the output shaft and are arranged side-by-side along the axial direction. For example, a disc motor may include two stator assemblies and one rotor assembly disposed between the two stator assemblies in an axial direction; or two rotor assemblies and one stator assembly arranged between the two rotor assemblies in the axial direction; or one rotor assembly and one stator assembly arranged side by side in the axial direction. Alternatively, the present application is not limited to the above-described motor configurations, and a disc motor including any number of stator and rotor assemblies arranged in an axial direction is within the scope of the present application. Fig. 2 shows a perspective view of a disc motor 1 comprising two rotor assemblies 20 and one stator assembly 30 sandwiched between the two rotor assemblies 20. In which the output shaft of the disc motor 1 is mounted in the through hole 12.

For the sake of clarity, in the present application, the direction in which the central axis of the output shaft (not shown) of the disc motor 1 extends is the axial direction Z, the radial direction R extends radially perpendicularly to the axial direction Z, and the circumferential direction C surrounds the axial direction Z, which directions are indicated in fig. 4 and 7, respectively.

The stator assembly 30 of the disc motor includes a plurality of stator cores and stator coils wound around the respective stator cores, and the rotor assembly 20 includes rotor discs in a plane perpendicular to the axial direction and magnets, such as permanent magnets, disposed on the rotor discs. The stator coil generates a magnetic field having axial magnetic lines of force that pass through an axial air gap between the stator assembly and the rotor assembly. A rotor disk of the rotor assembly is fixed to the output shaft and rotates along with a rotating magnetic field generated by the stator coil together with magnets provided on the rotor disk.

Fig. 3 is another view of fig. 2 with one rotor assembly 20 removed, exposing the arrangement of stator coils of the stator assembly 30. Fig. 4 is a front view of fig. 3, showing an arrangement of stator coils of the stator assembly 30 in fig. 3 in a cross section perpendicular to the axial direction.

As shown in fig. 3, the stator assembly 30 of the disc motor 1 includes a stator housing 32 fixed to a housing (not shown) of the disc motor 1 and stator coils housed within the stator housing 32, the stator housing 32 defining a plurality of compartments 36 spaced apart in the circumferential direction C by a plurality of spacers 34, each compartment 36 housing a set of corresponding inner and outer stator coils 110, 210.

Referring to fig. 3 and 4, the stator coils of the stator assembly 30 include an inner set of stator coils 100 located radially inward and thus closer to the central axis of the output shaft and an outer set of stator coils 200 located radially outward and thus farther from the central axis of the output shaft. The inner and outer stator coil groups 100 and 200 respectively include a plurality of (e.g., 12 in the illustrated embodiment) inner stator coils 110 (only one inner stator coil is denoted by a reference numeral in fig. 3 and 4) and an equal number of outer stator coils 210 (only one outer stator coil is denoted by a reference numeral in the drawings) that are arranged uniformly in the circumferential direction C around the axial direction Z. Each of the inner stator coils 110 has a corresponding outer stator coil 210 located radially outward thereof, and for example, in fig. 2, the outer stator coil corresponding to the inner stator coil labeled with reference numeral 110 is the outer stator coil labeled with reference numeral 210.

Fig. 5 shows an enlarged view of one of the inner stator coils 110 and the outer stator coil 210 radially corresponding thereto.

As shown in fig. 5, the inner stator coil 110 includes an inner stator core (not shown) located radially inward thereof, and the wire is wound around the inner stator core in a winding direction W indicated by an arrow (or, in another embodiment, in a direction opposite to the illustrated direction W) to form the inner stator coil 110.

In the sectional view of fig. 5, the outer contour of the inner stator coil 110 is substantially fan-shaped, and has a first side edge 132 and a second side edge 134 that are opposite in the circumferential direction C, and has an inner side edge 136 that is located radially innermost and an inner side edge 138 that is located radially outermost.

The inner stator core of each inner stator coil 110 has a wire wound portion that is substantially trapezoidal or substantially rectangular or substantially square or substantially sectorial in cross section, and for the inner stator core of each inner stator coil 110, the wire wound portion has a contour that conforms to the inner contour of the inner stator coil 110 in the cross section perpendicular to the axial direction and is elongated in the axial direction Z.

In some embodiments, the inner stator core of each inner stator coil 110 may include only a wire-wound portion located inside the inner stator coil 110. In still other embodiments, to achieve fixation of the stator assembly to the motor housing or stator housing, the inner stator core of each inner stator coil 110 may further include other extension portions integrally formed with or attached to the wire wound portion. For example, the inner stator core of each inner stator coil 110 may be generally "I" or "T" shaped, i.e., further include other portions extending therefrom transverse to the wire-wound portions.

Similarly, as shown in fig. 3 to 5, the outer contour of the outer-layer stator coil 210 is also substantially fan-shaped in the cross-sectional view, and has a first side edge 232 and a second side edge 234 opposite in the circumferential direction C, and has an inner side edge 236 located on the radially innermost side and an outer side edge 238 located on the radially outermost side.

Likewise, the outer-layer stator core of each outer-layer stator coil 210 has a wire-wound portion that is substantially trapezoidal or substantially rectangular or substantially square or substantially sectorial in the sectional view, and for each outer-layer stator core, the wire-wound portion has a contour that conforms to the inner contour of the outer-layer stator coil 210 in the sectional view perpendicular to the axial direction and is elongated along the axial direction Z.

In some embodiments, the outer stator core of each outer stator coil 210 may include only the wire-wound portion around which it is wound. In still other embodiments, to achieve fixation of the stator assembly to the motor housing or stator housing, the outer stator core of each outer stator coil 210 may also include other extensions that are integral with or attached to the wire wound section as desired. For example, the inner stator core of each outer stator coil 210 may be generally "I" or "T" shaped, i.e., further including other portions extending therefrom transverse to the wire-wound portions.

The inner stator core of each inner stator coil 110 may be the same shape as the outer stator core of each outer stator coil 210, or may be different.

In the present application, the inner stator coils 110 of the stator assembly 30 are radially aligned with the outer stator coils 210, meaning that the first and second side edges 132, 134 of each inner stator coil 110 are substantially radially aligned with the corresponding first and second side edges 232, 234 of the outer stator coils 210, respectively, and thus the scallop wrap angles (corresponding to the angles of the two side edges relative to the central axis of the output shaft) of the inner and outer stator coils 110, 210 are substantially equal.

As in the stator assembly structure described above, when the inner circumferential portion constituted by the inner side edges 136 of all the inner layer stator coils 110 has the highest allowable temperature, the number of turns (turns) N1 of each inner layer stator coil 110 is substantially equal to that of each stator coil in the related art. However, the outer circumferential portion formed by the outer-layer edges 236 of all the outer-layer stator coils 210 has not yet reached the maximum allowable temperature, so the number of turns N2 of each outer-layer stator coil 210 may be larger than that of each stator coil in the related art, and thus can carry a larger current. Because the number of turns of the outer layer stator coil group 200 is increased, more energy can be input, and the power density of the disc type motor can be improved.

Fig. 6 shows a schematic view of the rotor assembly 20 and fig. 7 is a front view of fig. 6, but only clearly showing the arrangement of the magnets of the rotor assembly 20 in a section perpendicular to the axial direction Z. The rotor assembly 20 includes a rotor disk 25 and a plurality of magnets attached to the rotor disk 25.

Corresponding to the stator assembly 30 including the inner set of stator coils 100 and the outer set of stator coils 200, the magnets of the rotor assembly 20 also include an inner set of magnets 300 located radially inward and thus closer to the central axis of the output shaft and an outer set of magnets 400 located radially outward and thus further from the central axis of the output shaft. Inner and outer magnet groups 300 and 400 include the same number of inner and outer magnets 310 and 410, respectively, arranged in circumferential direction C about axial direction Z. Each inner magnet 310 in inner magnet set 300 has one outer magnet 410 located radially outward of and corresponding to it, e.g., inner magnets 310 and 410 having reference numbers in fig. 6-8 are radially corresponding inner and outer magnets.

The inner layer magnets 310 constituting the inner layer magnet group 300 are divided into a plurality of inner layer magnet subgroups 310A arranged in the circumferential direction C and slightly spaced apart from each other in the circumferential direction C, each inner layer magnet subgroup 310A including two or more inner layer magnets 310. In the illustrated embodiment, the inner layer magnets 310 include 10 inner layer magnet subgroups 310A, and each inner layer magnet subgroup 310 is constituted by 5 inner layer magnets 310 adjacent in the circumferential direction C.

Accordingly, the outer layer magnets 410 constituting the outer layer magnet group 400 are divided into a plurality of outer layer magnet subgroups 410A arranged in the circumferential direction C and slightly spaced apart from each other in the circumferential direction C, each outer layer magnet subgroup 410A including two or more outer layer magnets 410. In the illustrated embodiment, the outer layer magnets 410 include 10 outer layer magnet subsets 410A, each outer layer magnet subset 410 being made up of 5 outer layer magnets 410 that are adjacent in the circumferential direction C. Two outer-layer magnet subgroups 410A adjacent in the circumferential direction and two inner-layer magnet subgroups 310A have a circumferential gap therebetween.

Referring to fig. 8, the inner and outer magnet subsets 310A and 410A and each inner and outer magnet 310 and 410 correspond radially, i.e., the inner magnet 310 has first and second opposite edges 332 and 334 in the circumferential direction C, the outer magnet 410 has first and second opposite edges 432 and 434 in the circumferential direction C, the first edge 332 of the inner magnet 310 and the first edge 432 of the outer magnet 410 are substantially aligned in the radial direction R, and the second edge 334 of the inner magnet 310 and the second edge 434 of the outer magnet 410 are substantially aligned in the radial direction R. The inner layer magnet 310 and the outer layer magnet 410 have radially innermost inner edges 336 and 436, respectively, and radially outermost outer edges 338 and 438, respectively. Thus, the inner layer magnet 310 has a sector shape defined by first and second side edges 332 and 334, an inner side edge 336 and an outer side edge 338, the outer layer magnet 410 has a sector shape equal by first and second side edges 432 and 434, an inner side edge 436 and an outer side edge 438, and the radially corresponding sector shape defined by the inner layer magnet 310 has a substantially equal sector wrap angle as the sector shape of the outer layer magnet 410.

The inner and outer circumferential portions formed by the inner and outer edges 336 and 338 of all the inner magnets 310 of the inner magnet group 300 of the rotor assembly 20 are substantially aligned with the inner and outer circumferential portions formed by the inner and outer edges 136 and 138 of each of the inner stator coils 110 of the inner stator coil group 100 of the stator assembly, respectively, in the axial direction Z, and the inner and outer circumferential portions formed by the inner and outer edges 436 and 438 of all the outer magnets 410 of the outer magnet group 400 of the rotor assembly 20 are substantially aligned with the inner and outer circumferential portions formed by the inner and outer edges 236 and 238 of each of the outer stator coils 210 of the outer stator coil group 200 of the stator assembly, in the axial direction Z.

Optionally, the number M1 of circumferentially arranged inner or outer stator coils 110 or 210 contained in the inner or outer stator coil set 100 or 200 of the stator assembly is greater than the number M2 of circumferentially arranged inner or outer magnets 310 contained in the inner or outer magnet set 300 or 400 of the rotor assembly, preferably the number M1 is 1.5 times the number M2.

The preferred embodiments of the present application are described above with reference to the accompanying drawings. It will be appreciated by persons skilled in the art that the above description is merely exemplary and is not intended to limit the scope of the application to the specific embodiments shown in the figures and described above. The specific structure or parameters of the disc motor may be changed as desired without departing from the principles of the present application, such as, but not limited to: the number of inner or outer stator coils included in the inner or outer stator coil group; the number of inner or outer magnets included in the inner or outer magnet group; a ratio of a radial dimension of the first or both side edges of the inner layer stator coil to the first or both side edges of the outer layer stator coil, that is, a ratio of a radial dimension of the wire wound portion of the inner layer stator core to a radial dimension of the wire wound portion of the outer layer stator core; the circumferential dimension of the inner or outer edge of the inner or outer layer stator coil; the size of the radial air gap between the outer circumferential portion of the inner stator coil and the inner circumferential portion of the outer stator coil, and so on. The scope of protection of this application is only limited by the claims.

Claims (11)

1. A disc motor comprising:

an output shaft defining a central axis and defining an axial direction extending along the central axis, a radial direction perpendicular to the axial direction and a circumferential direction around the axial direction;

a stator assembly mounted around the output shaft and fixed relative to a housing of the disc motor, the stator assembly including an inner set of stator coils and an outer set of stator coils, the inner and outer sets of stator coils including a plurality of inner stator coils and a plurality of outer stator coils, respectively, evenly arranged in a circumferential direction and having an equal first number, each inner stator coil having a corresponding outer stator coil aligned in a radial direction and located on an outer side thereof away from a central axis; and

a rotor assembly mounted to the output shaft and rotating therewith, the rotor assembly including an inner magnet set and an outer magnet set, the inner and outer magnet sets respectively including a plurality of inner magnets and a plurality of outer magnets arranged in a circumferential direction and having an equal second number, each inner magnet having a corresponding outer magnet aligned in a radial direction and located on an outer side thereof away from the central axis.

2. The disc motor according to claim 1, wherein in a cross section perpendicular to an axial direction, the inner layer stator coil has first and second side edges that are opposite in a circumferential direction, the outer contour of the outer layer stator coil has first and second side edges that are opposite in the circumferential direction, and the first and second side edges of the inner layer stator coil are substantially radially aligned with the first and second side edges of the outer layer stator coil, respectively.

3. The disc motor according to claim 2, wherein outer contours of the inner-layer stator coil and the outer-layer stator coil have substantially equal angles with respect to a central axis of the output shaft in a cross section perpendicular to an axial direction.

4. A disc motor according to any one of claims 1 to 3, wherein the stator assembly includes a stator housing fixed to the disc motor, the stator housing including a plurality of compartments spaced apart in a circumferential direction by a plurality of spacers, each compartment housing one inner stator coil and an outer stator coil radially aligned therewith.

5. The disc motor according to any one of claims 1 to 4, wherein the inner-layer magnet group includes a plurality of inner-layer magnet sub-groups arranged in the circumferential direction and spaced apart from each other, each inner-layer magnet sub-group including a plurality of inner-layer magnets adjoining in the circumferential direction; accordingly, the outer layer magnet group includes a plurality of outer layer magnet subgroups arranged in the circumferential direction and spaced apart from each other, each outer layer magnet subgroup including a plurality of outer layer magnets adjoining in the circumferential direction.

6. The disc motor according to claim 5, wherein, in a cross section perpendicular to the axial direction, the outer contour of the inner layer magnet has first and second circumferentially opposite side edges, the outer contour of the outer layer magnet has first and second circumferentially opposite side edges, and the first and second side edges of the inner layer magnet are substantially radially aligned with the first and second side edges of the outer layer magnet, respectively.

7. The disc motor according to claim 6, wherein outer contours of the inner and outer magnets have substantially equal angles with respect to a central axis of the output shaft in a cross section perpendicular to an axial direction.

8. The disc motor according to any one of claims 1 to 7, wherein the inner-layer stator coil and the outer-layer stator coil include an inner-layer core and an outer-layer core, respectively, and lead wires are wound on lead wire wound portions of the inner-layer core and the outer-layer core, respectively, to form the inner-layer stator coil and the outer-layer stator coil.

9. The disc motor according to claim 8, wherein the wire wound portions of the inner core and the outer core have a substantially fan-like or substantially trapezoidal shape in a cross section perpendicular to an axial direction.

10. A disc motor according to any one of claims 1-9, wherein the first number is greater than the second number, preferably the first number is 1.5 times the second number.

11. The disk motor according to any one of claims 1 to 10,

the at least one stator assembly is two stator assemblies and the at least one rotor assembly is one rotor assembly, wherein the one rotor assembly is arranged between the two stator assemblies in the axial direction; or

The at least one stator assembly is one stator assembly and the at least one rotor assembly is two rotor assemblies, wherein the one stator assembly is disposed between the two rotor assemblies in the axial direction; or

The at least one stator assembly includes one stator assembly and the at least one rotor assembly includes one rotor assembly, wherein the one stator assembly and the one rotor assembly are arranged side-by-side in the axial direction.

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