KR102307859B1 - Spherical wheel motor and control system thereof - Google Patents

Abstract

The present invention relates to a spherical wheel motor and a control system thereof, and more particularly, to a spherical rotor; and a stator surrounding the upper surface of the rotor. The rotor has a spherical outer shell, a first axial magnet extending in a horizontal direction within the outer shell, a second axial magnet extending opposite the first axial magnet in the horizontal direction within the outer shell, and the axial magnet in the outer shell and a rotating magnet belt provided in the form of a belt with the first axial magnet and the second axial magnet as a central axis. The rotating magnet belt includes a plurality of first rotating magnets and a plurality of second rotating magnets alternately arranged with each other. The stator may include a base surrounding an upper surface of the rotor; and a plurality of coil belts provided on the base to cross each other on the top of the base. Each of the coil belts includes a plurality of coils.

Description

Spherical wheel motor and its control system {SPHERICAL WHEEL MOTOR AND CONTROL SYSTEM THEREOF}

The present invention relates to a spherical wheel motor and its control system. More particularly, it relates to a spherical wheel motor including a rotating magnet and an axial magnet and a control system thereof.

A technology for a three-dimensional motor with free rotation capability is being actively studied. First, there is a method of driving a sphere using a large number of motors with existing shafts. The Ball-Bot or Ball-Pin Tire, which drives the sphere by mounting several motors on the outside of the sphere, has been developed, and the Sphero, which drives by mounting a motor with an existing shaft inside the sphere, has been developed. has been developed. Second, there is a method of using a multiple degree of freedom motor using a permanent magnet. A joint robot capable of movement in degrees of freedom and a permanent magnet type multi-degree-of-freedom motor capable of position control for robots have been developed. Third, there is a spherical wheel motor using an induction method. A spherical induction motor with a spherical surface as a metal conductive layer and a coil and inverter as a structure was developed.

An object of the present invention is to provide a spherical wheel motor having excellent rotational motion and rotational control.

The present invention is a spherical rotor; and a stator surrounding an upper surface of the rotor, wherein the rotor has a spherical outer shell, a first axial magnet extending in a horizontal direction within the outer shell, and the first axial magnet in the horizontal direction within the outer shell; a second axial magnet extending to face each other and a rotating magnet belt provided in a belt form with the first axial magnet and the second axial magnet as a central axis in the outer shell, wherein the rotating magnet belts are alternately arranged with each other and a plurality of first rotating magnets and a plurality of second rotating magnets, wherein the stator includes: a base surrounding an upper surface of the rotor; and a plurality of coil belts provided on the base to cross each other on the top of the base, each of the coil belts providing a spherical wheel motor including a plurality of coils.

The rotor may further include an interposition in the outer shell, and the interposition may include the same material as the outer shell.

The rotor may further include an interposition in the outer shell, and the interposition may be substantially empty.

The first axis magnet and the second axis magnet may contact each other.

Each of the first rotating magnets and each of the second rotating magnets may contact each other.

Each of the coil belts includes a first coil and a second coil positioned at both ends, and the uppermost part of the first coil and the uppermost part of the second coil are the uppermost part of the first axial magnet and the second axial magnet. It may be positioned at a higher level than the uppermost part, and the lowermost part of the first coil and the lowermost part of the second coil may be positioned at a lower level than the lowermost part of the first axial magnet and the lowermost part of the second axial magnet.

Each of the coil belts may include a third coil on the top of the base.

The rotor and the stator may be spaced apart from each other.

It may further include a bearing provided between the rotor and the stator.

It may further include a position detector connected to the first coil or the second coil.

The first axial magnet may be an N-pole magnet, and the second axial magnet may be an S-pole magnet.

Each of the first rotating magnets may be an N-pole magnet, and each of the second rotating magnets may be an S-pole magnet.

The present invention is a spherical rotor; and a stator surrounding an upper surface of the rotor, wherein the rotor has a spherical outer shell, a first axial magnet extending in a horizontal direction within the outer shell, and the first axial magnet in the horizontal direction within the outer shell; a second axial magnet extending to face each other and a rotating magnet belt provided in a belt form with the first axial magnet and the second axial magnet as a central axis in the outer shell, wherein the rotating magnet belts are alternately arranged with each other and a plurality of first rotating magnets and a plurality of second rotating magnets, wherein the stator includes: a base surrounding an upper surface of the rotor; and a plurality of coil belts provided on the base, wherein each of the coil belts provides a spherical wheel motor including a plurality of coils.

The base may include a base opening provided at the top of the base.

It may further include position detectors provided on a sidewall of the base exposed by the base opening.

The position detectors may be arranged to correspond to a direction in which the coils adjacent to the base opening are arranged.

It may further include a rotation detector including a disk in contact with the outer shell through the base opening.

The disk is rotatable in a first direction about an axis parallel to a circumferential surface of the disk as a central axis, and the rotation detector further includes a first encoder provided next to the disk, wherein the first encoder is Rotation information may be obtained by detecting the rotation of the s in the first direction.

The disk is rotatable in a second direction intersecting the first direction, and the rotation detector further comprises a second encoder provided above the disk, wherein the second encoder is configured to rotate the disk in the second direction. Rotation information can be obtained by detecting the rotation.

The rotation detector may further include a connection part connecting the disk and the second encoder, and the disk may be provided between some parts of the connection part.

The spherical wheel motor according to the present invention includes shaft magnets and a rotating magnet belt, and thus has excellent rotational motion and rotational control.

1A is a front view of a spherical wheel motor according to the present invention;
Fig. 1B is a cross-sectional view taken along line A-A' of Fig. 1A.
1C is a cross-sectional view taken along line B-B' of FIG. 1A.
2 is a view for explaining a rotating magnet belt and shaft magnets.
3 is a view for explaining the operation of the spherical wheel motor according to the present invention.
4A to 4H are views for explaining the counter electromotive force generated in the coils according to the rotation of the rotating magnetic belt.
5A is a block diagram for explaining a first embodiment of a control system according to the present invention.
FIG. 5B is a detailed view of area A of FIG. 5A .
6A is a block diagram for explaining a second embodiment of a control system according to the present invention.
FIG. 6B is a detailed view of area B of FIG. 6A .
FIG. 6C is a detailed view of region C of FIG. 6A .
7A is a plan view of a spherical wheel motor according to the present invention.
7B is a cross-sectional view taken along line A-A' of FIG. 7A.
8A is a plan view of a spherical wheel motor according to the present invention.
8B is a cross-sectional view taken along line A-A' of FIG. 8A.
8C is a view for explaining the position detector according to FIG. 8A.

Advantages and features of the present invention, and methods for achieving them, will become apparent with reference to the embodiments described below in detail in conjunction with the accompanying drawings. However, the present invention is not limited to the embodiments disclosed below, but may be implemented in various different forms, only this embodiment allows the disclosure of the present invention to be complete, and common knowledge in the technical field to which the present invention belongs It is provided to fully inform the possessor of the scope of the invention, and the present invention is only defined by the scope of the claims. Like reference numerals refer to like elements throughout the specification.

The terminology used herein is for the purpose of describing the embodiments and is not intended to limit the present invention. As used herein, the singular also includes the plural unless specifically stated otherwise in the phrase. As used herein, 'comprises' and/or 'comprising' refers to the presence of one or more other components, steps, operations and/or devices mentioned. or addition is not excluded.

Hereinafter, embodiments of the present invention will be described in detail.

1A is a front view of a spherical wheel motor according to the present invention, FIG. 1B is a cross-sectional view taken along line A-A' of FIG. 1A, FIG. 1C is a cross-sectional view taken along line B-B' of FIG. 1A, and FIG. 2 is a rotating magnet belt and axial magnets.

1A to 1C and 2 , the spherical wheel motor according to the present invention may include a rotor 100 and a stator 200 . The rotor 100 may be in the form of a sphere. The surface of the rotor 100 may be divided into an upper surface and a lower surface based on the center of the rotor 100 . The stator 200 may be provided to surround the upper surface of the rotor 100 .

The rotor 100 may include an outer shell 110 , a rotating magnet belt 170 , a first shaft magnet 140 , a second shaft magnet 150 , and an intervening portion 160 . The outer shell 110 may have a hollow sphere shape. In other words, the outer shell 110 may form a surface of the rotor 100 . A first shaft magnet 140 and a second shaft magnet 150 may be provided in the outer shell 110 . The first axis magnet 140 and the second axis magnet 150 may extend in a horizontal direction. The first axis magnet 140 and the second axis magnet 150 may extend to face each other. One end of the first shaft magnet 140 may be in contact with the outer shell 110 . One end of the second axis magnet 150 may be in contact with the outer shell 110 . For example, the ends of the first and second axis magnets 140 and 150 may be bent to correspond to the inner surface of the outer shell 110 . As another example, the ends of the first and second axis magnets 140 and 150 may be flat. In this case, a flat recess may be provided on the inner surface of the outer shell 110 to correspond to the end, and the end may contact the recess. As shown, the first axis magnet 140 and the second axis magnet 150 may be in contact with each other. Unlike the drawings, the first axis magnet 140 and the second axis magnet 150 may be spaced apart from each other. When the first shaft magnet 140 and the second shaft magnet 150 are spaced apart from each other, a connection element (not shown) may be provided between the first shaft magnet 140 and the second shaft magnet 150 . For example, the first axis magnet 140 may be an N-pole magnet, and the second axis magnet 150 may be an S-pole magnet. As another example, the first axial magnet 140 may be an S pole magnet, and the second axial magnet 150 may be an N pole magnet. The first axis magnet 140 and the second axis magnet 150 may have a cylindrical shape.

A rotating magnet belt 170 may be provided in the outer shell 110 . The rotating magnet belt 170 may be provided in the form of a belt with the first axial magnet 140 and the second axial magnet 150 as central axes. In other words, the rotating magnet belt 170 may be provided in the form of a belt with the first axial magnet 140 and the second axial magnet 150 as central axes. The rotating magnet belt 170 may surround side surfaces of the first axial magnet 140 and the second axial magnet 150 . The rotating magnet belt 170 may include a plurality of first rotating magnets 120 and a plurality of second rotating magnets 130 . Although each of the first rotating magnets 120 and the second rotating magnets 130 is illustrated as six, it may not be limited thereto. The first rotating magnets 120 and the second rotating magnets 130 may be alternately disposed with each other. In other words, the rotating magnet belt 170 may be provided while the first rotating magnets 120 and the second rotating magnets 130 are alternately connected. The rotating magnet belt 170 may be in contact with the outer shell 110 . The rotating magnet belt 170 may be spaced apart from the first axial magnet 140 and the second axial magnet 150 . For example, the first rotating magnets 120 may be N-pole magnets, and the second rotating magnets 130 may be S-pole magnets. As another example, the first rotating magnets 120 may be S-pole magnets, and the second rotating magnets 130 may be N-pole magnets. As shown, each of the first rotating magnets 120 and each of the second rotating magnets 130 may contact each other. Unlike the drawings, each of the first rotating magnets 120 and each of the second rotating magnets 130 may be spaced apart from each other. When each of the first rotating magnets 120 and each of the second rotating magnets 130 are spaced apart from each other, between each of the first rotating magnets 120 and each of the second rotating magnets 130 . A connecting element (not shown) may be provided.

An interposition 160 may be provided in the outer shell 110 . For example, the intervening part 160 may be a substantially empty space in the outer shell part 110 . As another example, the interposition 160 may include a solid material that fills the space in the outer shell 110 . In this case, the intervening part 160 may include the same material as the outer shell part 110 .

The stator 200 may include a base 280 and coil belts 201 . The base 280 may surround the upper surface of the rotor 100 . In other words, the base 280 may surround the upper surface of the outer shell 110 . The upper surface of the base 280 may have a shape similar to the upper surface of the outer shell 110 .

A plurality of coil belts 201 may be provided on the base 280 . The coil belts 201 may be in the form of an arc. Each of the coil belts 201 may cross the upper surface of the base 280 . The coil belts 201 may overlap each other on the top of the base 280 . In other words, the coil belts 201 may cross each other on top of the base 280 . The coil belts 201 are shown as four, but may not be limited thereto.

Each of the coil belts 201 may include first to seventh coils 210 , 220 , 230 , 240 , 250 , 260 , and 270 arranged on a straight line in a plane. The first to seventh coils 210 , 220 , 230 , 240 , 250 , 260 , and 270 may be sequentially provided on the base 280 . A first coil 210 and a seventh coil 270 may be positioned at both ends of each of the coil belts 201 . The uppermost part of the first coil 210 and the uppermost part of the seventh coil 270 may be located at a higher level than the uppermost part of the first axial magnet 140 and the uppermost part of the second axial magnet 150, and the first coil ( The lowermost portion of the 210 and the lowermost portion of the seventh coil 270 may be located at a lower level than the lowermost portion of the first axial magnet 140 and the lowermost portion of the second axial magnet 150 . The fourth coil 240 may be provided at the top of the stator 200 . In other words, the fourth coil 240 may be provided on the top of the base 280 . The coil belts 201 may overlap each other around the fourth coil 240 . In other words, one fourth coil 240 may be included in the plurality of coil belts 201 . The second coil 220 and the third coil 230 may be provided between the first coil 210 and the fourth coil 240 . The fifth coil 250 and the sixth coil 260 may be provided between the fourth coil 240 and the seventh coil 270 . As illustrated, the first to seventh coils 210 , 220 , 230 , 240 , 250 , 260 , and 270 may be spaced apart from each other. Unlike the drawings, the first to seventh coils 210 , 220 , 230 , 240 , 250 , 260 , and 270 may contact each other. Although one coil belt 201 is illustrated as including seven first to seventh coils 210 , 220 , 230 , 240 , 250 , 260 , and 270 , the number of coils may not be limited thereto. Each of the first to seventh coils 210 , 220 , 230 , 240 , 250 , 260 , and 270 may include a ferrite core.

Position detectors 290 connected to each of the first coils 210 or each of the seventh coils 270 may be provided. The position detectors 290 may detect the position of the rotor 100 . The position detectors 290 may be a Hall sensor or a mouse sensor.

The stator 200 and the rotor 100 may be spaced apart from each other. In other words, a separation space 310 may be provided between the stator 200 and the rotor 100 . For example, the rotor 100 may be spaced apart from the stator 200 by magnetic levitation. As another example, a bearing may be provided in the separation space 310 .

The rotor 100 of the driving wheel motor according to the present invention may rotate in the first direction D1 with the first shaft magnet 140 and the second shaft magnet 150 as central axes. In addition, the rotor 100 may rotate in the second direction D2 with the vertical axis C-C' as the central axis.

The driving wheel motor according to the present invention may have improved rotational movement force and rotational control force compared to the prior art. In the driving wheel motor, since the rotating magnet belt 170 includes a plurality of first rotating magnets 120 and a plurality of second rotating magnets 130 , rotational kinetic force may be excellent. Since the driving wheel motor includes the first shaft magnet 140 and the second shaft magnet 150 , rotation control power may be excellent.

3 is a view for explaining the operation of the spherical wheel motor according to the present invention.

Referring to FIG. 3 , a magnetic field may be generated by applying a current to each of the coil belts 201 . In other words, a magnetic field may be generated by applying a current to the first to seventh coils 210 , 220 , 230 , 240 , 250 , 260 , and 270 . The magnetic field generated by each of the coil belts 201 may rotate the first axial magnet 140 , the second axial magnet 150 , and the rotating magnet belt 170 . Accordingly, the rotor 100 may rotate.

One coil belt 201 may generate torque in one direction with respect to the rotating magnet belt 170 . As shown, the four coil belts 201 apply a first torque (T_1), a second torque (T_2), a third torque (T_3) and a fourth torque (T_4) with respect to the rotating magnet belt 170 . can cause The magnitudes of the X-direction torque T_X and the Y-direction torque T_Y may be derived as shown in Equation 1 below according to the magnitudes of the first to fourth torques T_1, T_2, T_3, and T_4.

[Equation 1]

T_X = T_1 + T_2*Cos45°+ T_4*Cos135°

T_Y = T_2*Sin45°+ T_3 + T_4*Sin135°

The magnitudes of the first to fourth torques T_1, T_2, T_3, and T_4 may be derived according to Equation 2 below.

[Equation 2]

T_(1~4) = ((I_1*E_1) + (I_2*E_2) + (I_3*E_3) + (I_4*E_4) + (I_5*E_5) + (I_6*E_6) + (I_7*E_7)) /w_m

In Equation 2 above, I_(1-7) is a current flowing in each of the first to seventh coils 210,220,230,240,250,260,270 included in each of the coil belts 201, and E_(1-7) is each A counter electromotive force acting on each of the first to seventh coils 210 , 220 , 230 , 240 , 250 , 260 , and 270 included in the coil belts 201 , W_m is the rotational angular velocity of the rotating magnetic belt 170 . The counter electromotive force acting on each of the first to seventh coils 210 , 220 , 230 , 240 , 250 , 260 , and 270 may be generated according to the rotation of the rotating magnet belt 170 .

The back electromotive force acting on the first to seventh coils 210 , 220 , 230 , 240 , 250 , 260 , and 270 may be derived according to Equation 3 below.

[Equation 3]

E_(1~7) = F_(1~7)*S_(1~7)

In Equation 3 above, F_(1-7) is a coefficient according to the angle and the angular velocity of the rotating magnetic belt 170 and the angle formed by each of the first to seventh coils 210,220,230,240,250,260,270 with the rotating magnetic belt 170, S_(1 to 7) is a coefficient according to the shape of each of the first to seventh coils 210 , 220 , 230 , 240 , 250 , 260 and 270 .

According to the first to fourth torques (T_1, T_2, T_3, T_4) acting on the rotating magnet belt 170 as described above, the rotating magnet belt 170 moves the first axis magnet 140 and the second axis magnet 150 . ) may be rotated in the first direction D1 with respect to the central axis.

Separately from the first to fourth torques T_1 , T_2 , T_3 , and T_4 , the first axis magnet 140 and the second magnet Torque may be generated in the shaft magnet 150 in the second direction D2 . Accordingly, the first axis magnet 140 and the second axis magnet 150 use the vertical axis (C-C', see FIGS. 1C and 2 ) of the rotor 100 as a central axis in the second direction (D2). can be rotated with

Since the first axial magnet 140 and the second axial magnet 150 rotate in the second direction D2, the rotating magnet belt 170 rotates along the vertical axis C-C' of the rotor 100, FIGS. 1C and 1C and FIG. 2) as a central axis, and may rotate in the second direction D2. Accordingly, the first direction D1 in which the rotating magnet belt 170 rotates may change an angle formed in a plane with the first to fourth torques T_1 , T_2 , T_3 , and T_4 . Each of the first to fourth torques T_1, T_2, T_3, and T_4 applies a larger rotational force to the rotating magnet belt 170 as the angle formed with the first direction D1 in which the rotating magnetic belt 170 rotates is smaller. can

Consequently, the rotor 100 may rotate in the first direction D1 with the first axis magnet 140 and the second axis magnet 150 as central axes, and the vertical axis C of the rotor 100 . -C' (refer to FIGS. 1C and 2) may be rotated in the second direction D2 as a central axis.

4A to 4H are views for explaining the counter electromotive force of the first to seventh coils generated according to the rotation of the rotating magnetic belt.

4A to 4H, when the rotating magnetic belt 170 rotates in a predetermined direction in parallel with respect to one coil belt 201 as shown in FIG. 4H, first to The counter electromotive force of the seventh coils 210 , 220 , 230 , 240 , 250 , 260 and 270 may be sequentially described with reference to FIGS. 4A to 4G . 4A to 4G , the vertical axis represents the magnitude ratio and direction of the counter electromotive force, and the horizontal axis represents the rotation angle of the rotating magnet belt 170 . According to the rotation angle of the rotating magnet belt 170, the polarity of the magnet passing through the magnetic field generated in the coil is shown on the horizontal axis. Illustratively, referring to FIG. 4C , when the N-pole magnet passes through the magnetic field generated by the third coil 230 according to the rotation of the rotating magnet belt 170, the magnitude of the back electromotive force is gradually increased. When the S pole magnet passes through the magnetic field generated by the third coil 230, the magnitude of the back electromotive force gradually increases, and the direction of the back electromotive force is opposite to that when the N pole magnet passes.

5A is a block diagram for explaining a first embodiment of the control system according to the present invention, and FIG. 5B is a detailed view of area A of FIG. 5A.

5A and 5B , the control system may include a control unit 400 . The controller 400 may include a plurality of polyphase inverters 410 and a controller 430 . The controller 430 may output a control signal to each of the polyphase inverters 410 . Each of the polyphase inverters 410 may output a current signal to the first to seventh coils 210 , 220 , 230 , 240 , 250 , 260 , and 270 included in one coil belt 201 . In this case, the plurality of polyphase inverters 410 may output a current signal to one fourth coil 240 .

The controller 430 may output a control signal to the polyphase inverters 410 based on the position signal PS provided from the position detector 290 . The controller 430 may calculate the magnitude of the current to be output to the first to seventh coils 210 , 220 , 230 , 240 , 250 , 260 and 270 . The controller 430 may include an MCU for the above operation. The controller 430 may generate a control signal by performing a current magnitude calculation to rotate the rotor 100 according to a user's command. For example, the control signal may be a pulse width modulation (PWM) signal.

The polyphase inverters 410 may convert a DC signal from a DC voltage source into an AC signal based on the control signal and output the converted DC signal to the first to seventh coils 210 , 220 , 230 , 240 , 250 , 260 , and 270 . To this end, the polyphase inverters 410 may include transistors 411 . For example, two transistors 411 connected in series with each other may be defined as a pair of transistors, and each of the polyphase inverters 410 may include a plurality of pairs of transistors connected in parallel. The number of transistor pairs may be equal to the number of coils. Each of the plurality of transistors 411 may include various devices such as MOSFETs and BJTs, but is not limited thereto. For example, the polyphase inverters 410 may include a plurality of freewheeling diodes connected in parallel to each of the plurality of transistors 411 . The plurality of freewheeling diodes may be configured to prevent damage to the transistors 411 due to the current charged in the first to seventh coils 210 , 220 , 230 , 240 , 250 , 260 , and 270 .

The plurality of transistors 411 may be turned on or off based on a control signal. Each of the two transistors 411 included in the transistor pair may receive an inverted control signal. For example, one transistor 411 may be turned on by receiving a high level control signal, and another transistor 411 connected in series may be turned off by receiving a low level control signal. In this case, a low-level current may be provided to the coil corresponding to the transistor pair. As such, the first to seventh coils 210 , 220 , 230 , 240 , 250 , 260 , and 270 may receive alternating current under the control of the polyphase inverters 410 .

6A is a block diagram for explaining a second embodiment of a control system according to the present invention, FIG. 6B is a detailed view of area B of FIG. 6A, and FIG. 6C is a detailed view of area C of FIG. 6A.

6A to 6C , the control system may include a control unit 400 . The controller 400 may include a plurality of polyphase inverters 410 and a single-phase inverter 420 . The controller 430 may output a control signal to each of the polyphase inverters 410 and the single-phase inverter 420 . Each of the polyphase inverters 410 may output a current signal to the first to third coils 210 , 220 , 230 and the fifth to seventh coils 250 , 260 , and 270 included in one coil belt 201 . The single-phase inverter 420 may output a current signal to the fourth coil 240 .

The controller 430 may output a control signal to the polyphase inverters 410 and the single-phase inverter 420 based on the position signal PS provided from the position detector 290 . The controller 430 may calculate the magnitude of the current to be output to the first to seventh coils 210 , 220 , 230 , 240 , 250 , 260 and 270 . The controller 430 may include an MCU for the above operation. The controller 430 may generate a control signal by performing a current magnitude calculation to rotate the rotor 100 according to a user's command. For example, the control signal may be a pulse width modulation (PWM) signal.

The polyphase inverters 410 may convert a DC signal from a DC voltage source into an AC signal based on the control signal and output it to the first to third coils 210 , 220 , 230 and the fifth to seventh coils 250 , 260 , 270 . . To this end, the polyphase inverters 410 may include transistors 411 . Each of the polyphase inverters 410 may include a plurality of transistor pairs connected in parallel. The number of transistor pairs may be equal to the number of coils. Each of the plurality of transistors 411 may include various devices such as MOSFETs and BJTs, but is not limited thereto. For example, the polyphase inverters 410 may include a plurality of freewheeling diodes connected in parallel to each of the plurality of transistors 411 . The plurality of freewheeling diodes may be configured to prevent damage to the transistors 411 due to the current charged in the first to third coils 210 , 220 , and 230 and the fifth to seventh coils 250 , 260 and 270 .

The plurality of transistors 411 may be turned on or off based on a control signal. Each of the two transistors 411 included in the transistor pair may receive an inverted control signal. For example, one transistor 411 may be turned on by receiving a high level control signal, and another transistor 411 connected in series may be turned off by receiving a low level control signal. In this case, a low-level current may be provided to the coil corresponding to the transistor pair. As such, the first to third coils 210 , 220 , and 230 and the fifth to seventh coils 250 , 260 , and 270 may receive alternating current under the control of the polyphase inverters 410 .

The single-phase inverter 420 may convert a DC signal from a DC voltage source into an AC signal based on the control signal and output the converted DC signal to the fourth coil 240 . To this end, the single-phase inverter 420 may include transistors 421 . The single-phase inverter 420 may include two transistor pairs connected in parallel. Each of the plurality of transistors 421 may include various devices such as MOSFETs and BJTs, but is not limited thereto. For example, the single-phase inverter 420 may include a plurality of freewheeling diodes connected in parallel to each of the plurality of transistors 421 . The plurality of freewheeling diodes may be configured to prevent damage to the transistors 421 due to the current charged in the fourth coil 240 .

The plurality of transistors 421 may be turned on or off based on a control signal. Each of the two transistors 421 included in the transistor pair may receive an inverted control signal. For example, one transistor 421 may be turned on by receiving a high level control signal, and another transistor 421 connected in series may be turned off by receiving a low level control signal. In this case, a low-level current may be provided to the coil corresponding to the transistor pair. As such, the fourth coil 240 may receive AC current under the control of the single-phase inverter 420 .

7A is a plan view of a spherical wheel motor according to the present invention, and FIG. 7B is a cross-sectional view taken along line A-A' of FIG. 7A. For brevity of description, the same reference numerals are used for the same components described with reference to FIGS. 1A to 1C and 2 , and overlapping descriptions will be omitted.

7A and 7B , a base opening 281 may be provided at the top of the base 280 of the stator 200 . The base opening 281 may pass through the base 280 . The base opening 281 may be circular in plan view. Each of the coil belts 201 may include first to third coils 210 , 220 , 230 and fifth to seventh coils 250 , 260 , and 270 arranged on a straight line in a plane.

Position detectors 290 may be provided in the base opening 281 . The position detectors 290 may be provided on a sidewall of the base 280 exposed by the base opening 281 . Eight position detectors 290 may be provided on the sidewall of the base 280 . Each of the eight position detectors 280 may be disposed to correspond to a direction in which the eight coils 230 and 250 adjacent to the base opening 281 are disposed. In other words, eight position detectors 290 may be arranged radially. The position detectors 290 may be one of a Hall sensor, a camera, and a mouse sensor. The position detectors 290 may detect the position of the rotor 100 and provide the position signal PS to the controller 430 (see FIGS. 5A and 5B ). As the eight position detectors 290 are provided in the base opening 281 , the position signal PS transmitted to the controller 430 can be relatively precise, and the controller 430 uses the polyphase inverters 410 . A control signal output to the . may be relatively precise.

8A is a plan view of a spherical wheel motor according to the present invention, FIG. 8B is a cross-sectional view taken along line A-A' of FIG. 8A, and FIG. 8C is a view for explaining the position detector according to FIG. 8A. The same reference numerals are used for the same components described with reference to FIGS. 1A to 1C and 2 , and overlapping descriptions will be omitted.

8A to 8C , a base opening 281 may be provided at the top of the base 280 of the stator 200 . The base opening 281 may pass through the base 280 . The base opening 281 may be circular in plan view. Each of the coil belts 201 may include first to third coils 210 , 220 , 230 and fifth to seventh coils 250 , 260 , and 270 arranged on a straight line in a plane. The coil belts 201 may not overlap each other.

A support wall 282 connected to a sidewall of the base 280 exposed by the base opening 281 may be provided. A plate 283 may be provided on the support wall 282 . The support wall 282 may support the edge of the lower surface of the plate 283 . The plate 283 may have the shape of a circular plate, and the support wall 282 may have the shape of a circular pipe. The base opening 281 may be blocked from the outside by the support wall 282 and the plate 283 .

Position detector 290 may be supported by plate 283 . The position detector 290 may include a first encoder 291 , a first bearing 292 , a connection part 293 , a disk 294 , a second encoder 295 , and second bearings 296 .

The disk 294 may have the shape of a circular plate. The circumferential surface of the disk 294 may be in contact with the outer shell 110 of the rotor 100 . The disk 294 may contact the outer shell 110 of the rotor 100 through the base opening 281 . Second bearings 296 may be provided on both sides of the disk 294 . One of the second bearings 296 and the second encoder 295 may be connected. A connection 293 may be provided on the disk 294 . The connection part 293 may include an upper part 293a and a lower part 293b. The lower portion 293b of the connecting portion 293 may include a first portion 293b1 connected to the upper portion 293a and second portions 293b2 extending from the first portion 293b1 . A disk 294 may be provided between the second portions 293b2 . Each of the second parts 293b2 may be connected to a second bearing 296 . The upper part 293a of the connection part 293 may pass through the plate 283 . A first bearing 292 may be provided on the upper part 293a of the connection part 293 . The first bearing 292 and the first encoder 291 may be connected.

The position detector 290 may detect the position of the rotor 100 . Hereinafter, a method for the position detector 290 to detect the position of the rotor 100 will be described. When the rotor 100 rotates, the disk 294 may rotate by friction between the outer shell 110 and the disk 294 . The disk 294 may rotate in a third direction D3 with a first axis C1 parallel to the circumferential surface of the disk 294 as a central axis, and a second axis perpendicular to the first axis C1. It may rotate in a fourth direction D4 with reference to (C2) as a central axis. When the disk 294 rotates in the third direction D3 , the second encoder 295 detects the rotation of the disk 294 to obtain rotation information. When the disk 294 rotates in the fourth direction D4 , the connection part 293 may rotate in the fourth direction D4 . When the connector 293 rotates in the fourth direction D4 , the first encoder 291 may detect the rotation of the connector 293 to obtain rotation information. Based on the rotation information of the first and second encoders 291,295, the position of the rotor 100 may be detected. The position detector 290 may provide the position signal PS to the controller 430 (see FIGS. 5A and 5B ). As the position detector 290 including the first and second encoders 291,295 is provided, the position signal PS transmitted to the controller 430 may be relatively precise, and the controller 430 may use the polyphase inverters. A control signal output to 410 may be relatively precise.

As mentioned above, although embodiments of the present invention have been described with reference to the accompanying drawings, those of ordinary skill in the art to which the present invention pertains can implement the present invention in other specific forms without changing its technical spirit or essential features. You will understand that there is Therefore, it should be understood that the embodiments described above are illustrative in all respects and not restrictive.

100: rotor
140: first axis magnet
150: second axis magnet
170: rotating magnet belt
200: stator
201: coil belt
280: base

Claims (20)

spherical rotor; and
and a stator surrounding the upper surface of the rotor;
The rotor has a spherical outer shell, a first axial magnet extending in a horizontal direction within the outer shell, a second axial magnet extending opposite the first axial magnet in the horizontal direction within the outer shell, and the axial magnet in the outer shell A rotating magnet belt provided in a belt form with the first axial magnet and the second axial magnet as a central axis,
The rotating magnet belt includes a plurality of first rotating magnets and a plurality of second rotating magnets arranged alternately with each other,
The stator is:
a base surrounding the upper surface of the rotor; and a plurality of coil belts provided on the base to cross each other on the top of the base,
Each of the coil belts includes a plurality of coils,
A spherical wheel motor in which the plurality of coils of any one of the coil belts form an arc shape with the first and second axis magnets as central axes on the upper surface of the base.
The method of claim 1,
The rotor further comprises an interposition in the outer shell,
The interposition portion comprises the same material as the outer shell portion of the spherical wheel motor.
The method of claim 1,
The rotor further comprises an interposition in the outer shell,
wherein the intervening portion is a substantially empty spherical wheel motor.
The method of claim 1,
The first shaft magnet and the second shaft magnet are in contact with each other.
The method of claim 1,
each of the first rotating magnets and each of the second rotating magnets are in contact with each other.
The method of claim 1,
Each of the coil belts includes a first coil and a second coil located at both ends,
The top of the first coil and the top of the second coil are located at a higher level than the top of the first shaft magnet and the top of the second shaft magnet;
A lowermost portion of the first coil and a lowermost portion of the second coil are positioned at a lower level than a lowermost portion of the first axial magnet and lowermost portions of the second axial magnet.
The method of claim 1,
wherein each of the coil belts includes a third coil on the top of the base.

The method of claim 1,
The spherical wheel motor in which the rotor and the stator are spaced apart from each other.
9. The method of claim 8,
The spherical wheel motor further comprising a bearing provided between the rotor and the stator.
7. The method of claim 6,
The spherical wheel motor further comprising a position detector connected to the first coil or the second coil.
The method of claim 1,
The first shaft magnet is an N-pole magnet, and the second shaft magnet is an S-pole magnet.
The method of claim 1,
each of the first rotating magnets is a N pole magnet and each of the second rotating magnets is an S pole magnet.
spherical rotor; and
and a stator surrounding the upper surface of the rotor;
The rotor has a spherical outer shell, a first axial magnet extending in a horizontal direction within the outer shell, a second axial magnet extending opposite the first axial magnet in the horizontal direction within the outer shell, and the axial magnet in the outer shell A rotating magnet belt provided in a belt form with the first axial magnet and the second axial magnet as a central axis,
The rotating magnet belt includes a plurality of first rotating magnets and a plurality of second rotating magnets arranged alternately with each other,
The stator is:
a base surrounding the upper surface of the rotor; and a plurality of coil belts provided on the base,
Each of the coil belts includes a plurality of coils,
A spherical wheel motor in which the plurality of coils of any one of the coil belts form an arc shape with the first and second axis magnets as central axes on the upper surface of the base.
14. The method of claim 13,
wherein the base includes a base opening provided at the top of the base.
15. The method of claim 14,
and position detectors provided on a sidewall of the base exposed by the base opening.
16. The method of claim 15,
The position detectors are disposed so as to correspond to a direction in which the coils adjacent to the base opening are disposed.
15. The method of claim 14,
The spherical wheel motor further comprising a rotation detector including a disk in contact with the outer shell through the base opening.
18. The method of claim 17,
The disk is rotatable in a first direction with an axis parallel to the circumferential surface of the disk as a central axis,
The rotation detector further comprises a first encoder provided next to the disk,
The first encoder is a spherical wheel motor to obtain rotation information by detecting the rotation of the disk in the first direction.
19. The method of claim 18,
The disk is rotatable in a second direction intersecting the first direction,
The rotation detector further comprises a second encoder provided on the disk,
The second encoder is a spherical wheel motor to obtain rotation information by detecting the rotation of the disk in the second direction.
20. The method of claim 19,
The rotation detector further includes a connection unit for connecting the disk and the second encoder,
A spherical wheel motor in which the disk is provided between some portions of the connecting portion.

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