Axial magnetic flux motor

Abstract

The purpose of the present invention is to provide an axial magnetic flux motor comprising: a motor housing that forms an inner space; a stator that is disposed in the inner space of the motor housing and includes a stator core, a coil, and a stator bracket; a rotor that is disposed so as to face one side of the stator in the axial direction and includes a rotor base plate and a plurality of permanent magnets; and a gear unit disposed so as to face the other side of the stator in the axial direction and provided with a sun gear axially coupled to the rotor, a planet gear engaging with the sun gear, and a ring gear having an inner surface engaging with the planet gear.

Description

Axial flux motor

[0001] The present invention relates to an axial flux motor, and more particularly, to an axial flux motor in which a rotor and a stator can be arranged axially.

[0002]

[0003] Recently, as the number of vehicles has increased and it has become difficult to drive personal vehicles, the number of people using public transportation or small mobility vehicles for transportation has been increasing.

[0004] Representative examples of small mobility devices include electric bicycles, electric kickboards, and electric mini bikes, and among these, demand for electric bicycles is increasing.

[0005] These small mobility devices are usually equipped with a motor and have a structure in which the wheels are rotated by the rotational force of the motor.

[0006] Most of the motors used in conventional small mobility are radial type motors. Radial motors have a long axial length, so when applied to small mobility, the motor part protrudes, causing inconvenience to the user when getting on and off.

[0007] To solve the above-mentioned problems, an axial type motor capable of reducing the length in the axial direction has recently been developed.

[0008] However, conventional axial motors typically have a structure where the shaft rotates to transmit rotational power, requiring a separate reducer with gears to be connected. This increases the overall volume, making boarding and disembarking inconvenient and degrading aesthetics.

[0009] Against this backdrop, the inventor of the present invention developed a compact axial magnetic motor capable of effectively rotating the wheels of a small mobility device by arranging a gear part inside the motor housing and rotating the housing rather than the shaft, and confirmed its effectiveness, thereby completing the present invention.

[0010]

[0011] The present invention was created to solve the above-described problem, and its purpose is to provide an axial magnetic motor for small mobility in which a gear is arranged inside a motor housing so that the motor housing rotates by the rotational force of a rotor.

[0012] In addition, the present invention aims to develop an axial flux motor capable of providing a uniform height between permanent magnets attached to a rotor.

[0013] The problems to be solved by the present invention are not limited to the problems mentioned above, and other problems not mentioned will be clearly understood by those skilled in the art from the description below.

[0014]

[0015] The above-described object is achieved by an axial flux motor including a motor housing forming an internal space according to one embodiment of the present invention, a stator disposed in the internal space of the motor housing and including a stator core, a coil, and a stator bracket, a rotor disposed axially oppositely on one side of the stator and including a rotor base plate and a plurality of permanent magnets, and a gear portion disposed axially oppositely on the other side of the stator and including a sun gear axially coupled to the rotor, a satellite gear meshed with the sun gear, and a ring gear having an inner circumferential surface meshed with the satellite gear.

[0016] Additionally, the ring gear is coupled with the motor housing, so that the motor housing can be rotated by power transmission from the gear unit.

[0017] Additionally, the rotor base plate may have a plurality of magnetic grooves formed on a surface facing the stator to which a plurality of permanent magnets are coupled.

[0018] Additionally, the magnetic home may have an adhesive discharge port formed on the surface where the permanent magnet comes into contact when the permanent magnet is bonded with an adhesive.

[0019] In addition, the stator core is provided in multiple pieces, the stator bracket has a guide groove formed along the outer surface into which the multiple stator cores are inserted, and the stator core may have a fixed piece formed on one side to be inserted into the guide groove.

[0020] Additionally, the guide home may have a tapered shape with a narrower width on the inside.

[0021] Additionally, the satellite gear includes a satellite gear rotation shaft and a bearing that rotatably connects the satellite gear to the satellite gear rotation shaft, and the satellite gear rotation shaft and the bearing may be provided as a pair to prevent the satellite gear from coming off.

[0022] In addition, the stator further includes a satellite gear base having one side supporting the other side of a satellite gear supported by the stator, the satellite gear rotation shaft includes a first satellite gear rotation shaft connecting the stator and one side of the satellite gear, and a second satellite gear rotation shaft connecting the satellite gear base and the other side of the satellite gear, and the bearing includes a first bearing connected to one side of the satellite gear, and a second bearing connected to the other side of the satellite gear, the first bearing having the first satellite gear rotation shaft inserted into the opening and the outer circumference inserted into the hollow of the satellite gear, and the second bearing having the second satellite gear rotation shaft inserted into the opening and the outer circumference inserted into the hollow of the satellite gear.

[0023]

[0024] According to an axial magnetic motor for small mobility according to one embodiment of the present invention, the entire housing of the motor can be rotated to effectively rotate the wheels of the small mobility.

[0025] In addition, according to an axial magnetic flux motor according to one embodiment of the present invention, an adhesive discharge port is formed in a groove where permanent magnets are coupled, so that the height between permanent magnets can be uniform, thereby improving rotation efficiency.

[0026]

[0027] FIG. 1 is a perspective view of an axial flux motor according to one embodiment of the present invention.

[0028] Figure 2 is an exploded perspective view of an axial flux motor according to one embodiment of the present invention.

[0029] Fig. 3 is an exploded perspective view of the stator and gear included in the axial flux motor of Fig. 1.

[0030] Fig. 4 is a front view of a stator included in the axial flux motor of Fig. 1.

[0031] Fig. 5 is a perspective view of a rotor included in the axial flux motor of Fig. 1.

[0032] FIGS. 6 and 7 are schematic drawings showing a portion of a gear unit according to one embodiment of the present invention.

[0033] Fig. 8 is a cross-sectional view showing an exploded state of an axial flux motor according to one embodiment of the present invention.

[0034]

[0035] The embodiments described in this specification and the configurations illustrated in the drawings are merely preferred examples of the disclosed invention, and there may be various modified examples that can replace the embodiments and drawings of this specification at the time of filing of this application.

[0036] The same reference numbers or symbols used in each drawing of this specification represent parts or components that perform substantially the same functions. The shapes and sizes of elements in the drawings may be exaggerated for clarity.

[0037] The terminology used herein is for the purpose of describing embodiments and is not intended to limit and / or restrict the disclosed invention. The singular expression includes the plural expression unless the context clearly indicates otherwise. In this specification, the terms "comprises" or "has" and the like are intended to indicate the presence of a feature, number, step, operation, component, part, or combination thereof described in the specification, but do not preclude the presence or addition of one or more other features, numbers, steps, operations, components, parts, or combinations thereof.

[0038] While terms including ordinal numbers, such as "first," "second," etc., used herein may be used to describe various components, the components are not limited by these terms, and these terms are used solely to distinguish one component from another. For example, without departing from the scope of the present invention, a first component could be referred to as a second component, and similarly, a second component could also be referred to as a first component.

[0039]

[0040] Hereinafter, an axial flux motor according to one embodiment of the present invention will be described in detail with reference to the drawings.

[0041] FIG. 1 is a perspective view of an axial flux motor according to one embodiment of the present invention. FIG. 2 is an exploded perspective view of an axial flux motor according to one embodiment of the present invention. FIG. 3 is an exploded perspective view of a stator and a gear unit included in the axial flux motor of FIG. 1. FIG. 4 is a front view of a stator included in the axial flux motor of FIG. 1. FIG. 5 is a perspective view of a rotor included in the axial flux motor of FIG. 1. FIGS. 6 and 7 are schematic drawings showing a portion of a gear unit according to one embodiment of the present invention.

[0042] Referring to FIGS. 1 and 2, the axial flux motor (10) includes a motor housing (100), a stator (200), a rotor (300), and a gear unit (400).

[0043]

[0044] The motor housing (100) has an internal space (S) and is provided with a stator (200) and a rotor (300) described later. The motor housing (100) may include an upper casing (120) and a lower casing (140).

[0045] The upper casing (120) has an internal space (S) formed. The upper casing (120) has a perforation formed in the axial direction.

[0046] The lower casing (140) can be implemented in a circular plate shape. The lower casing (140) can be combined with the upper casing (120) to close the opening of the upper casing (120), thereby closing the internal space of the upper casing (120).

[0047]

[0048] The stator (200) is placed in the internal space of the upper casing (120). As shown in FIG. 3, the stator (200) includes a stator core (220), a coil (222), a stator bracket (240), and a stator holder (260).

[0049] A plurality of stator cores (220) may be provided. The stator cores (220) may be arranged at regular intervals along the circumferential direction from the center.

[0050] The coil (222) can be wound on the outer surface of each stator core (220) so as to generate magnetic flux in the axial direction.

[0051] The stator bracket (240) fixes the stator core (220). The stator bracket (240) may be formed of an insulator. The stator bracket (240) may be provided in a circular shape. The stator bracket (240) may be hollow in the axial direction. The stator bracket (240) may be formed with a guide groove (242) into which the stator core (220) is inserted. The number of guide grooves (242) may correspond to the number of stator cores (220). The guide grooves (242) may have a concave shape from the outside toward the center to guide the stator core (220) to be inserted.

[0052] The guide groove (242) may be formed along the outer circumference of the stator bracket (240). The guide groove (242) may be provided in a tapered shape. For example, as illustrated in FIG. 4, it may be provided in a tapered shape whose width becomes narrower toward the center.

[0053] At this time, the stator core (220) is formed with a fixed piece (224) having a shape that is inserted into a guide groove (242) on one side. The fixed piece (224) may be formed in a "T" shape. The fixed piece (224) may be formed integrally with the stator core (220). The fixed piece (224) includes an insertion portion (2241) and a fixed portion (2242).

[0054] One side of the insertion portion (2241) is joined to the stator core (220). The insertion portion (2241) can be formed in a shape corresponding to the guide groove (242).

[0055] The fixed part (2242) is connected to the other side of the insertion part (2241). The fixed part (2242) can be formed with a larger area than the insertion part (2241).

[0056] According to this, the insertion part (2241) and the fixing part (2242) are combined to have a “T” shape, so that the stator core (220) is inserted along the guide groove (242) of the stator bracket (240) by the insertion part (2241), and the fixing part (2242) supports and fixes the core (220) on the other side of the stator bracket (240).

[0057] The stator holder (260) is provided in a cylindrical shape with a hollow space formed in the axial direction. The stator holder (260) may be formed with a bracket groove (262) into which a stator bracket (240) is inserted in the axial direction. The bracket groove (262) may be formed with an inner surface of a size corresponding to the outer surface of the stator bracket (240).

[0058] According to this, the fixed piece (224) of the stator core (220) is coupled to the guide groove (242) formed in the stator bracket (240), and the stator holder (260) is coupled to surround the outer side of the stator bracket (240), thereby preventing the stator core (220) from being detached.

[0059]

[0060] The rotor (300) is arranged on one side of the stator (200). When power is supplied to the stator (200), the rotor (300) interacts with the stator (200) to rotate. The rotor (300) is arranged axially opposite to the stator (200). The rotor (300) includes a rotor base plate (320) and a permanent magnet (340).

[0061] The rotor base plate (320) may be provided in a circular shape, as illustrated in FIG. 5. The rotor base plate (320) is positioned facing the stator (200). Specifically, the rotor base plate (320) may be positioned in a direction in which the stator core (220) is coupled. The rotor base plate (320) is formed with a magnetic coupling groove (322) to which a permanent magnet (340) described below is coupled.

[0062] A plurality of magnetic coupling grooves (322) may be formed. The magnetic coupling grooves (322) may be formed along the circumferential direction of the rotor base plate (320). The magnetic coupling grooves (322) may be formed at a position facing the upper portion of the stator core (220).

[0063] A permanent magnet (340) is bonded to the magnet coupling groove (322) using an adhesive. However, it is difficult to apply an equal amount of adhesive between the rotor base plate (320) and the permanent magnet (340), resulting in a height difference between the bonded permanent magnets (340), which reduces rotational efficiency. Accordingly, an adhesive discharge port (324) may be formed in the magnet coupling groove (322) to discharge excess adhesive when the permanent magnet (340) is bonded.

[0064] A permanent magnet (340) is inserted into a magnetic coupling groove (322) and coupled to the rotor base plate (320). A plurality of permanent magnets (340) are provided. The permanent magnets (340) can be arranged so that the N pole and the S pole are alternately exposed. If an odd number of permanent magnets (340) are provided, one pair of the plurality of permanent magnets is arranged with the same pole, so an even number of permanent magnets (340) must be provided.

[0065] Accordingly, even if the amount of adhesive is irregularly applied to the magnetic coupling groove (322), when the permanent magnets (340) are coupled, the excess adhesive is discharged through the adhesive discharge port (324), thereby minimizing the height difference between the permanent magnets (340) and increasing the degree of the air gap, thereby improving the rotation efficiency.

[0066]

[0067] The gear unit (400) transmits the rotational power of the rotor (300) to the motor housing (100) through a reduction ratio. The gear unit (400) includes a sun gear (420), a satellite gear (440), and a ring gear (460).

[0068] The sun gear (420) is coupled to one surface of the rotor (300) and rotates by the rotation of the rotor (300). As shown in Fig. 5, the sun gear (420) is coupled to a surface where a plurality of permanent magnets (340) of the rotor base plate (320) are coupled and can pass through the hollow of the stator holder (260).

[0069] The satellite gear (440) is engaged with the sun gear (420) and rotates by the rotation of the sun gear (420). The satellite gear (440) is coupled to one surface of the stator (200). For example, the satellite gear (440) may be coupled to one surface of the stator holder (260), as illustrated in FIG. 6. Specifically, the satellite gear (440) may be coupled to one surface of the stator holder (260) facing the satellite gear base (280) described below.

[0070] A plurality of satellite gears (440) may be provided. For example, three satellite gears (440) may be formed as illustrated in FIG. 7, but the number is not limited. The satellite gears (440) may be arranged at equal distances from the center of the satellite gear base (280). A plurality of satellite gears (440) may be arranged at equal intervals.

[0071] The satellite gear (440) has a hollow space formed axially in the center. The satellite gear (440) is connected to the stator holder (260) via a satellite gear rotation shaft (442). Specifically, the satellite gear (440) may be connected to the satellite gear rotation shaft (442) via a bearing (444).

[0072] The satellite gear rotation shaft (442) and bearing (444) are provided in multiple numbers to prevent the satellite gear (440) from being detached. For example, the satellite gear rotation shaft (442) and bearing (444) are provided in two numbers each to support the satellite gear (440) on both sides.

[0073] The satellite gear rotation shaft (442) includes a first satellite gear rotation shaft (4421) and a second satellite gear rotation shaft (4422). The first satellite gear rotation shaft (4421) has one end connected to the stator holder (260) and the other end connected to the satellite gear (440). The second satellite gear rotation shaft (4422) has one end connected to the satellite gear base (280) and the other end connected to the satellite gear (440).

[0074] The bearing (444) includes a first bearing (4441) and a second bearing (4442). The first bearing (4441) rotatably connects the satellite gear (440) to the first satellite gear rotation shaft (4421). Specifically, the first satellite gear rotation shaft (4421) is inserted into a hole of the first bearing (4441), and the outer circumference thereof is inserted into the hollow of the satellite gear (440). The second bearing (4442) rotatably connects the satellite gear (440) to the second satellite gear rotation shaft (4422). Specifically, the second satellite gear rotation shaft (4422) is inserted into a hole of the second bearing (4442), and the outer circumference thereof is inserted into the hollow of the satellite gear (440).

[0075] The satellite gear base (280) can be bolted to the stator holder (260). The stator holder (260) and the satellite gear base (280) can have grooves formed on their respective opposing surfaces to which the first satellite gear rotation shaft (4421) and the second satellite gear rotation shaft (4422) are respectively fixed.

[0076] According to this, since the satellite gear rotation shaft and bearing are provided in multiple pieces, the rotation efficiency is improved by reducing shaft bending compared to when the satellite gear (440) is supported on only one side.

[0077] The ring gear (460) is engaged with the satellite gear (440) and rotates by the rotation of the satellite gear (440). The ring gear (460) has gears formed on its inner surface and can be externally engaged with a plurality of satellite gears (440). The ring gear (460) is coupled to the interior of the upper casing (120).

[0078] According to the gear unit (400) described above, when AC power is applied to the stator (200), the rotor (300) is rotated by the permanent magnet (340) coupled to the rotor base plate (320), the sun gear (420) coupled to the rotor (300) is rotated, a plurality of satellite gears (440) coupled to one surface of the stator (200) and connected to the sun gear (420) by gears are rotated, and a ring gear (460) fixedly coupled to the inside of the upper casing (120) and connected to the plurality of satellite gears (440) by gears is rotated, thereby allowing the motor housing (100) to be rotated.

[0079]

[0080] Below, the coupling relationship between the motor housing (100), stator (200), rotor (300), and gear unit (400) is described.

[0081] Fig. 8 is a cross-sectional view showing an exploded state of an axial flux motor according to one embodiment of the present invention. Referring to Fig. 8, first, a stator (200) is formed with a stator fixing shaft (282) on one surface and is supported and fixed by passing through an upper casing (120). Specifically, a satellite gear base (280) coupled to a stator holder (260) has a stator fixing shaft (282) formed on the other surface of the surface to which a satellite gear (440) is coupled. At this time, the stator (200) is inserted into the internal space (S) of the upper casing (120), and the stator fixing shaft (282) is supported and fixed by passing through a hole formed in the upper casing (120).

[0082] Next, the upper casing (120) is rotatably coupled to the stator (200). Specifically, a bearing (B1) is inserted between the stator fixing shaft (282) and the hole so that the upper casing (120) is rotatably coupled to the stator (200). Then, the ring gear (460) coupled to the interior of the upper casing (120) is externally coupled to the satellite gear (440) coupled to the stator holder (260) and the satellite gear base (280).

[0083] Next, the rotor (300) is coupled to the stator (200). Specifically, a rotor fixing shaft (326) is formed on the rotor base plate (320) in a direction opposite to the stator (200). The rotor fixing shaft (326) is inserted into and coupled to a hollow space formed in the stator holder (260). A bearing (B2) is inserted between the rotor fixing shaft (326) and the hollow space of the stator holder (260) so that the rotor (300) is rotatably coupled.

[0084] Next, the lower casing (140) is fixedly connected to the upper casing (120). Specifically, the lower casing (140) is connected to a hole in the upper casing (120) to which the stator (200) is not connected. The lower casing (140) may be connected to the other side of the rotor (300) whose one side is rotatably connected to the stator (200). The lower casing (140) may have a protrusion (142) formed on a surface facing the rotor (300) to support the rotor (300). At this time, the rotor (300) may have a groove (328) formed on a surface facing the lower casing (140) that corresponds to the protrusion (142) of the lower casing (140). A bearing (B3) is inserted between the protrusion (142) and the groove (328) so that the other side of the rotor (300) is rotatably coupled to the lower casing (140).

[0085]

[0086] According to the above-described example, the gear unit according to one embodiment of the present invention has a rotor (300) arranged on one side of the stator (200) and a gear unit (400) arranged on the other side, so that the weight can be distributed more evenly than when the rotor (300) and the gear unit (400) are arranged on only one side of the stator (200), thereby having the effect of reducing shaft bending.

[0087] In addition, lubricating oil is generally applied to the gear section to prevent wear and lubricate the gears. If the gear section and the rotor are arranged in the same direction, there is a problem that the lubricant applied to the gear section contaminates the rotor. However, the present invention has the effect of preventing the rotor (300) from being contaminated by the lubricating oil applied to the gear section (400) by arranging the rotor (300) on one side of the stator (200) and the gear section (400) on the other side of the stator (200).

[0088]

[0089] Although all components constituting the embodiments of the present invention have been described above as being combined or operating in combination, the present invention is not necessarily limited to these embodiments. That is, within the scope of the purpose of the present invention, all components may be selectively combined and operated one or more times. In addition, terms such as "include," "comprise," or "have" described above, unless specifically stated to the contrary, mean that the corresponding component may be inherent, and therefore should be interpreted as including other components rather than excluding other components. All terms, including technical or scientific terms, have the same meaning as generally understood by a person of ordinary skill in the art to which the present invention pertains, unless otherwise defined. Commonly used terms, such as terms defined in a dictionary, should be interpreted as being consistent with the contextual meaning of the related technology, and shall not be interpreted in an ideal or overly formal sense, unless explicitly defined in the present invention.

[0090] The above description is merely an illustrative description of the technical idea of ​​the present invention, and those skilled in the art will appreciate that various modifications and variations may be made without departing from the essential characteristics of the present invention. Therefore, the embodiments disclosed in the present invention are not intended to limit the technical idea of ​​the present invention, but rather to explain it, and the scope of the technical idea of ​​the present invention is not limited by these embodiments. The scope of protection of the present invention should be interpreted by the following claims, and all technical ideas within a scope equivalent thereto should be interpreted as being included in the scope of the rights of the present invention.

Claims

1. Motor housing forming the internal space; A stator disposed in the inner space of the motor housing and including a stator core, a coil, and a stator bracket; A rotor including a rotor base plate and a plurality of permanent magnets, which are arranged axially opposite to one side of the stator; and An axial magnetic flux motor including a gear section having a sun gear axially coupled to the rotor and arranged opposite to the other side of the stator, a satellite gear meshed with the sun gear, and a ring gear having an inner circumferential surface meshed with the satellite gear.

2. In paragraph 1, The above ring gear is, An axial magnetic flux motor coupled to the above motor housing, wherein the motor housing rotates by power transmission from the gear unit.

3. In paragraph 1, The above rotor base plate, An axial magnetic flux motor in which a plurality of magnetic grooves are formed on a surface facing the stator to which the plurality of permanent magnets are coupled.

4. In paragraph 3, The above magnetic home, An axial magnetic flux motor having an adhesive discharge port formed on a surface where the permanent magnets come into contact when the permanent magnets are bonded with an adhesive.

5. In paragraph 1, The above stator core, Equipped in multiples, The above stator bracket, A guide groove is formed along the outer surface into which a plurality of stator cores are inserted, The above stator core, An axial magnetic flux motor having a fixed member formed on one side to be inserted into the above guide groove.

6. In paragraph 5, The above guide home is, An axial flux motor having a tapered shape with a narrower width on the inside.

7. In paragraph 1, The above satellite gear is, Satellite gear rotation axis; and Including a bearing that rotatably connects the satellite gear to the satellite gear rotation axis, The above satellite gear rotation shaft and the above bearing, Axial flux motors provided in pairs to prevent the above satellite gears from coming off.

8. In paragraph 7, The above stator, Further comprising a satellite gear base supporting the other side of the satellite gear supported on the stator, The above satellite gear rotation axis is, A first satellite gear rotation shaft connecting the stator and one side of the satellite gear; and It includes a second satellite gear rotation shaft connecting the satellite gear base and the other side of the satellite gear, The above bearings, A first bearing connected to one side of the satellite gear; and Includes a second bearing connected to the other side of the above satellite gear, The above first bearing, The first satellite gear rotation shaft is inserted into the hole, and the outer surface is inserted into the hollow of the satellite gear. The above second bearing, An axial magnetic flux motor in which a second satellite gear rotation shaft is inserted into a hole and an outer surface thereof is inserted into the hollow of the satellite gear.

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