KR20130107502A - Electric bike motor and manufacturing method of the same - Google Patents

Abstract

PURPOSE: An electric bike motor and a manufacturing method thereof are provided to improve the durability by fixing a permanent magnet to a back yoke. CONSTITUTION: A wheel is connected to a tire. A back yoke (113) is placed on the inner side of the wheel in the radial direction. A permanent magnet (115) is equipped in the inner side of the back yoke in the radial direction. A permanent magnet stopper (114) determines the position of the permanent magnet. A stator is equipped inside the permanent magnet.

Description

Electric bike motor and method of manufacturing the same

The present invention relates to a motor, and more particularly, to a motor that reduces manufacturing costs and improves manufacturing and reliability as well as efficiency.

More specifically, the present invention relates to an electric bike motor, and more particularly to a motor for driving wheels of an electric bike.

Generally, the motor transmits the rotational force of the rotor, i.e., the rotor, to the rotational shaft, and the rotational shaft drives the load. For example, the rotary shaft may be connected to the drum of the washing machine to drive the drum, and the fan may be connected to the fan of the refrigerator to supply cool air to the required space.

In the case of the electric bike, the rotation of the rotor can be directly converted to the rotation of the wheel or wheels to drive the electric bike. In the case of an electric bike, rather than the configuration in which the shaft rotates, it can be said that the role of relatively fixing the stator, that is, the stator. Thus, the wheel itself may be part of the stator configuration.

Here, the electric bike may include an electric bicycle, a scooter or an auto bike, and the electric bicycle may also be electric driving through manual driving through a pedal or driving of a motor.

On the other hand, in such a motor, the rotor is rotated by electromagnetic interaction with the stator, that is, the stator. To this end, a coil is wound on the stator, and as the current is applied to the coil, the rotor rotates with respect to the stator.

Electric bikes require a relatively large amount of power. Therefore, in general, three phase (three phases) power is used, and many BLC motors are provided with permanent magnets in the rotor. In addition, many brushless DC (BLDC) outer type motors in which the rotor rotates outside the stator are used.

As a BCD outer type motor used in a conventional electric bike, there are many cases in which the number of slots of the stator is 36, that is, the number of teeth is 36, and the number of poles of the rotor provided in the rotor is 48. And the coil which comprises each phase is connected in series.

However, since electric bikes are smaller than automobiles, the capacity of the battery is inevitably limited. Therefore, there is a problem that it is difficult to apply a large force through the low voltage supplied through the battery.

1 shows an example of an electric bike motor disclosed in the patent publication of US Pat. No. 6,278,216.

As shown, the wheel hub 1 and the shell 11 are integrally formed and coupled to the casing 12. Therefore, there is a problem that the portion 13 to which the casing 12 and the cover shell 11 are coupled is vulnerable. This is because the wheel hub 1 is configured to drive the wheels while supporting the wheels of the electric bike.

Of course, the wheel hub 1 may be connected with the tire or directly with the tire through the wheel spokes.

On the other hand, the yoke ring 31 is provided inside the casing 12 in the radial direction, and the permanent magnet 32 is provided inside the yoke ring 31. In addition, the stator 4 is provided at a radially inner side of the permanent magnet 32.

As shown, the yoke ring 31 is attached to the inside of the casing 12 in a separate configuration from the casing 12, and the permanent magnet 32 is attached to the inside of the yoke ring 31.

Unexplained reference numerals are as described in the above patent publication.

The problem is that a lot of time and money is required to process the yoke ring 31 to determine the position where the permanent magnet 32 is attached to the yoke ring 31.

In general, as shown in FIG. 2, the ring-shaped yoke, that is, the back yoke 31 may have a shape in which the inner side surface 31a is not processed, and as shown in FIG. 32b may be formed. Of course, the permanent magnet may be coupled to the groove 32b.

In the case of the back yoke illustrated in FIG. 2, the permanent magnet may be coupled only to the inner surface 31a of the back yoke 31, so that the permanent magnet may be removed. In the case of the back yoke illustrated in FIG. 3, the permanent magnet may be firmly coupled, but a lot of time and cost may be generated to process the back yoke 31. In addition, when the permanent magnet is attached through the groove 32b, the permanent magnet coupling position may be accurately aligned along the circumferential direction, but the permanent magnet coupling position in the height direction may not be accurate.

In the case of the back yoke 31 illustrated in FIG. 1, a lot of time and cost may be generated to process the back yoke 31 to form the groove 32a for coupling the permanent magnet. In addition, since at least a part of the permanent magnet should be inserted into the groove 32a, the width of the back yoke 31 is relatively large compared to the width of the permanent magnet. On the contrary, it can be said that the width of the permanent magnet is relatively smaller than that of the back yoke 31.

For this reason, when the width of the back yoke 31 is reduced in order to reduce the width of the motor in FIG. 2, the width of the permanent magnet is further reduced, making it difficult to manufacture a motor having a desired output. On the contrary, even if the width of the desired permanent magnet is determined, a problem in which the width of the back yoke 31 is further increased may occur.

In addition, since the width of the back yoke 31 is relatively larger than the width of the permanent magnet, magnetic flux loss due to the back yoke 31 may occur, thereby causing a problem of deterioration of the efficiency of the motor.

Therefore, there is a need to provide an electric bike motor that is easy to manufacture and can be firmly coupled to a permanent magnet. In addition, there is a need to provide an electric microphone motor in which the back yoke can be firmly fixed to the wheel.

Then, it is necessary to provide an electric microphone motor that can prevent the magnetic flux loss caused by the back yoke 31 by making the width of the back yoke 31 equal to the length of the permanent magnet.

The present invention basically aims to solve the above-mentioned problems.

Through the embodiments of the present invention, to provide an electric bike motor and a method of manufacturing the same that is easy to manufacture and enhanced durability.

Through the embodiment of the present invention, to provide an electric bike motor and a method of manufacturing the back yoke can be more firmly fixed to the wheel and the permanent magnet is more firmly fixed to the back yoke.

Through the embodiment of the present invention, to provide an electric bike motor and a method of manufacturing the same that can minimize the magnetic flux loss through the back yoke by making the width of the back yoke equal to the width of the permanent magnet.

Through the embodiment of the present invention, the permanent magnet can be more firmly fixed without processing the radially inner surface of the back yoke to which the permanent magnet is coupled to provide an electric bike motor easy to manufacture.

Through embodiments of the present invention, it is intended to provide an electric bike motor that can exert greater force in a given battery condition.

In order to achieve the above object, an embodiment of the present invention, an electric bike motor for driving the wheel of the electric bike, a wheel connected to the wheel; A back yoke provided at an inner side in the radial direction of the wheel; A permanent magnet provided in the radially inner side of the back yoke; A permanent magnet stopper formed integrally with the wheel and protruding radially inward longer than the thickness of the back yoke to determine a position at which the permanent magnet is provided; And it can provide an electric bike motor comprising a stator provided inside the permanent magnet.

The permanent magnet stopper may be provided on the left and right sides of the back yoke, respectively, and may be provided on the left or right side of the back yoke.

The wheel may include a wheel case formed in an annular shape to form the center of the wheel; And a wheel hub extending radially outward from the left and right sides of the wheel case and integrally formed with the wheel case.

It may include a motor cover is coupled to both sides of the wheel case and rotates integrally with the wheel case.

The wheel may be formed to surround all except the radially inner side of the ring-shaped back yoke.

The permanent magnet may be attached to the radially inner surface of the back yoke through an adhesive.

The permanent magnet may be attached to the radially inner surface of the back yoke and the inner surface of the permanent magnet stopper through an adhesive.

Preferably, the wheel is formed through casting while the back yoke is inserted into a mold, and the back yoke is coupled to the wheel.

Coils having three phases may be wound around a plurality of teeth of the stator, and coils of each phase may be connected in parallel.

The number of teeth is 36 in the circumferential direction, and coils of the same phase may be wound every three neighboring teeth.

The number of poles of the permanent magnet may be 40 along the circumferential direction. The number of the permanent magnets is 10, one permanent magnet may have four poles along the circumferential direction.

Coils of the same phase may be wound around three neighboring teeth and three neighboring teeth again to form a first sub coil, and a second sub coil symmetrically connected to the first sub coil may be formed. .

One end of the first and second sub coils may be fixed to a power terminal on u, and the other end of the first and second sub coils may be fixed to a neutral terminal.

One end of the sub coil may be fixed to the power terminal after being moved along the circumferential direction of one side of the stator, and the other end of the sub coil may be fixed to the neutral terminal after being moved along the circumferential direction of the other side of the stator. have. For example, the lead wires for the power connection may be disposed on the upper insulator, and the lead wires for the neutral point connection may be disposed on the lower insulator.

In order to achieve the above object, an embodiment of the present invention, inserting a back yoke having a ring shape of a ferromagnetic material in the mold; And a wheel manufacturing step of forming a wheel connected to the wheel of the electric bike on the radially outer side of the back yoke through casting or injection, and simultaneously coupling the back yoke to the wheel. Is formed integrally with the wheel and protrudes radially inward longer than the thickness of the back yoke, so that a permanent magnet stopper is formed to determine a coupling position of the permanent magnet coupled to the radially inner surface of the back yoke. A manufacturing method of an electric bike motor can be provided.

The wheel is preferably formed to surround all except the radially inner surface of the back yoke.

The permanent magnet stopper is preferably formed on one side or both sides of the back yoke.

The permanent magnet may be attached to the radially inner surface of the back yoke and the inner surface of the permanent magnet stopper through an adhesive.

Through the embodiment of the present invention, it is possible to provide an electric bike motor and a method of manufacturing the same that is easy to manufacture and enhanced durability.

Through the embodiment of the present invention, it is possible to provide an electric bike motor and a method of manufacturing the same that the back yoke may be more firmly fixed to the wheel and the permanent magnet may be more firmly fixed to the back yoke.

Through the embodiment of the present invention, it is possible to provide an electric bike motor and a method for manufacturing the same that can minimize the magnetic flux loss through the back yoke by making the width of the back yoke equal to the width of the permanent magnet.

Through the embodiment of the present invention, the permanent magnet can be more firmly fixed without processing the radially inner surface of the back yoke to which the permanent magnet is coupled can provide an electric bike motor easy to manufacture.

Through embodiments of the present invention, it is possible to provide an electric bike motor that can exert greater force in a given battery condition.

According to the embodiment of the present invention, it is possible to provide an electric bike motor that is easy to process wiring and easy to secure an insulation distance.

1 is a cross-sectional view of a conventional electric bike motor;
2 is a partial perspective view of an example of a back yoke applied to a conventional electric bike motor;
3 is a partial perspective view showing another example of a back yoke applied to a conventional electric bike motor;
4 is a perspective view showing an electric bike motor according to the embodiment of the present invention;
5 is a perspective view excluding the motor cover in FIG. 4;
6 is a partial sectional view showing an example of a wheel of an electric bike motor according to an embodiment of the present invention;
FIG. 7 is a partial cross-sectional view illustrating an embodiment of the wheel manufacture of FIG. 6; FIG.
8 is a partial cross-sectional view showing another example of a wheel of an electric bike motor according to an embodiment of the present invention;
9 is a partial cross-sectional view illustrating an embodiment of the wheel manufacture of FIG. 8;
10 is a connection diagram showing an example of a connection that can be applied to this embodiment;
11 is a perspective view showing an example of an insulator that can be applied to this embodiment;
12 is a partially enlarged view of Fig.

Hereinafter, with reference to the accompanying drawings will be described in detail a preferred embodiment according to the present invention.

First, the configuration of the electric bike motor according to the present embodiment will be described in detail with reference to FIGS. 4 and 5.

Figure 4 shows the appearance of the entire motor, Figure 5 shows before the motor cover is combined to show the stator.

The motor 100 may include a stator 140 and a rotor 110. Due to the characteristics of the electric bike motor, the rotor 110 may be referred to as a wheel 110, and hereinafter referred to as a wheel 110 for convenience of description.

The stator 140 is provided inside the wheel 110 in the radial direction, and the wheel 110 rotates with respect to the stator 140 to drive the wheel of the electric bike. The wheel 110 may be coupled to the tire to the outside as in the wheel of the vehicle to configure the wheel, it may be connected to the tire through the wheel flesh or the like to configure the wheel.

As will be described later, the wheel 110 may be configured to include a permanent magnet and a back yoke to form a rotor to form a BLDC outer rotor type motor as a whole. Here, the outer rotor means a type in which the rotor is driven radially outward from the outside of the stator.

The wheel 110 is formed in an annular shape and extends radially outward from the left and right of the wheel case 111 forming the center of the wheel and the wheel case 111, respectively, the wheel integrally formed with the wheel case 111 It may include a hub (112). Therefore, tires or spokes may be coupled to each other through the wheel case 111 and the wheel hub 112 to form a wheel.

The stator 140 may include an annular stator core 141 and a tooth 142 formed to protrude radially outward along the circumferential direction of the stator core 141.

A plurality of teeth 142 may be formed, and a coil (not shown) is wound around the teeth 142. Specifically, the tooth 142 is provided with an insulator not shown, and the coil is wound around the insulator. That is, insulation between the tooth 142 and the coil is made through the insulator. The coil and the insulator will be described later.

When power is applied to the coil, a rotating magnetic field is generated between the stator and the rotor, that is, the wheel 110, so that the wheel 110 rotates.

The stator 140 is configured to stop. Therefore, a configuration for fixing the stator 140 in an electric bike is required. To this end, a bracket 130 may be provided inside the stator 140. The brackets may be provided on the upper and lower sides of FIG. 5, respectively.

The shaft 130 may be provided at the center of the bracket 130. The shaft may be firmly fixed to the bracket 130. In addition, the bracket 130 may be a part of the stator 140. Therefore, the shaft 130 may be firmly fixed to the stator 140.

Specifically, both ends of the shaft 130 may be connected to a sprocket (not shown) for transmitting the load of the electric bike to the shaft 130. Thus, the load of the electric bike can be transmitted to the stator 140 through the sprocket and the shaft 130. Therefore, the shaft and stator do not rotate. Of course, the wheel 110 can rotate relative to the stator and the shaft.

Meanwhile, a coil may be formed in the stator 140 and electrical or electronic components may be provided. For example, a power connection connector 144 or a neutral terminal may be provided. In addition, a hall sensor and a substrate 145 for controlling the motor may be provided.

It is necessary to protect the stator 140 from the outside, and for this purpose, the motor cover 120 may be provided at both sides as shown in FIG. 4.

Here, the motor cover 120 should be rotated integrally with the wheel 110. To this end, a fastening hole (not shown) may be formed in the wheel hub 112 or the wheel case 110. In addition, a coupling hole 121 may be formed in the motor cover 120 to correspond to the fastening hole. Therefore, the motor cover 120 may be firmly fixed to the wheel 110 through the coupling hole 121 or the like. Through this, the wheel 110 and the motor cover 120 may be integrally rotated.

Of course, the shaft 130 may be provided through the motor cover 120. To this end, a shaft through hole 123 may be formed at the center of the motor cover 120. Then, the motor cover 120 should rotate about the shaft. To this end, the bearing 160 is preferably provided between the shaft and the motor cover 120. The motor cover 120 may be formed with a bearing seating portion 122 on which the bearing 160 may be seated.

The shaft 130 is fixed through the bearing 160 and the motor cover 120 relatively rotates integrally with the wheel 110 to drive the electric bike.

In the above it has been described in detail the configuration that can be applied to the motor according to an embodiment of the present invention.

Embodiments of the present invention may specifically provide a wheel 110 configuration and a method of manufacturing the wheel 110.

Hereinafter, the configuration of the wheel 110 and the manufacturing method of the wheel 110 will be described in detail with reference to FIGS. 6 to 9. 6-9, one end view of the wheel 110 is shown. It can be said that such a cross section constitutes the wheel 110. That is, the cross sections show a cross section in one radial direction. The cross sections rotate 360 degrees with respect to the wheel center to form an annular wheel.

First, an embodiment and a manufacturing method of the wheel 110 will be described in detail with reference to FIGS. 6 to 7.

As described above, the wheel 110 is formed in an annular shape and extends radially outward from the left and right or both sides of the wheel case 111 and the wheel case 111 forming the center of the wheel to be integrally formed with the wheel case. It may be made including a wheel hub 112.

A back yoke 113 may be provided at a radially inner side of the wheel 110. The back yoke 113 is preferably formed of a ferromagnetic material.

When a current flows through the coil of the stator 140, a magnetic flux is generated, and the back yoke 113 is preferably provided to form a passage through which the magnetic flux flows, that is, a magnetic path. In addition, a permanent magnet 115 may be provided at a radially inner side of the back yoke 113.

On the other hand, the back yoke 113 is provided on the radially outer side of the permanent magnet 115 to form a magnetic path, so the thickness of the back yoke 113 is very important. If the thickness of the back yoke 1130 is thin, the magnetic flux is saturated, and there is a limit of increasing the motor output even if the current is increased to produce a strong output. On the other hand, if the thickness of the back yoke is thick, selection of an appropriate thickness is very important because an increase in weight and material cost of the product occurs.

Here, the height of the back yoke 113 or the left and right widths (refer to FIG. 7) is preferably formed to be equal to the left and right widths of the permanent magnets 115. That is, when the left and right widths of the back yoke 113 facing the teeth 142 and the permanent magnets 115 are larger than the left and right widths of the permanent magnets 115 or the teeth 142, the left and right ends of the white yo 113 are fixed. This is because there is a risk that the loss of magnetic flux through This magnetic flux loss impairs the efficiency of the motor.

However, through this embodiment, it is possible to make the width of the back yoke 113 and the width of the permanent magnet 115 equal, and it is possible to implement this very easily. This can be easily implemented through the permanent magnet stopper 114 to determine the position of the permanent magnet 115.

The permanent magnet stopper 114 is preferably formed integrally with the wheel 110. And, it is preferable to protrude radially inward longer than the thickness of the back yoke 113. Thus, the back yoke 113 is surrounded by the wheel 110 except for the inner surface 113a to which the permanent magnet 115 is coupled. That is, the wheel 110 may be formed to wrap all except the radially inner surface of the back yoke. Through this, the back yoke 113 may be more firmly coupled to the permanent magnet 115. This is because at least three or more surfaces are surrounded by the wheel 110 based on the cross section of FIG.

On the other hand, the permanent magnet stopper 114 may be provided on each side. The permanent magnet stopper 114 may be formed extending in the radial direction longer than the thickness of the back yoke 113. Therefore, the permanent magnet stopper may be provided on the left and right or both sides of the back yoke 113, respectively.

The permanent magnet stoppers 114 respectively formed on both sides of the back yoke 113 form a step 116 to which the permanent magnets 115 are coupled. That is, the permanent magnet may be coupled to the wheel 110 through both end faces as well as the radial outer surface.

Specifically, the outer surface of the permanent magnet may be coupled to the back yoke 113 and both end surfaces of the permanent magnet may be coupled to the inner surface of the permanent magnet stopper 114, that is, the step 116. Likewise, all surfaces except the inner surface of the permanent magnet can be coupled to the wheel 110 and the back yoke 113, so that the permanent magnet can be more firmly fixed.

More specifically, the permanent magnet may be coupled to the back yoke 113 and the permanent magnet stopper 114 through an adhesive. The adhesive may be a bond. Therefore, it is possible to increase the bonding area and to form the bonding surface in multiple angles, so that permanent magnet removal can be prevented in advance.

Meanwhile, a groove 113 may be formed on a radially outer surface of the back yoke 113 so that the back yoke 113 is firmly coupled to the wheel 110. Through the groove 113, it is possible to increase the coupling area and to diversify the coupling angle.

As described above, the permanent magnet stopper 114 is integrally formed with the wheel 110. In other words, both constitute a body. It can be formed by casting or injection.

That is, the back yoke may be coupled to the wheel while the wheel is formed through casting or injection while the back yoke 113 is inserted into a mold. In addition, the wheel may be formed and at the same time the permanent magnet stopper 114 may be formed. In other words, the permanent magnet stopper 114 may be formed to surround both ends of the back yoke 113 and may be formed as a part of a wheel that further extends radially inward.

An embodiment of a manufacturing method will be described with reference to FIG. 7.

First, the back yoke is inserted into the molds 160 to 163.

The back yoke 113 may be formed of a ferromagnetic material, and may be formed in an annular shape. The back yoke may be used by cutting a pipe having the same diameter and thickness as the back yoke 113 to a desired width. Or it may be possible to make a long yoke to make a back yoke by welding.

It is preferable to heat the back yoke 113 to a constant temperature before inserting it. Of course, it will also be possible to heat after the insert. This is to reduce the temperature difference between the melt to form the wheel and the back yoke 113 so that the back yoke 113 can be more firmly coupled to the wheel 110 after cooling.

Thereafter, the wheels 110 may be formed by moving the upper and lower molds 160 and 161, the radially outer mold 162, and the radially inner mold to pour the melt into the mold. Thus, the back yoke can be coupled to the wheel at the same time as the wheel is formed. This may be referred to as a wheel manufacturing step.

Of course, the shape of the molds should be formed to correspond to the shape of the wheel 110 to be manufactured.

Permanent magnet stopper 114 may be formed in the wheel manufacturing step. That is, the permanent magnet stopper 114 may be formed as a part of the wheel 110. In particular, in order to form the permanent magnet stopper 114, the shapes of the upper and lower molds 160 and 161 and the inner mold 163 may be formed to correspond thereto.

When casting or injection is completed, the four molds are moved to remove the wheel 110 from the mold.

Through such a manufacturing method, it is possible to omit the processing of the back yoke 113 to which the permanent magnet is coupled. In addition, since the wheel formation, the coupling of the back yoke and the wheel, and the permanent magnet stopper through the wheel formation can all be made at the same time can be very economical and easily implemented.

On the other hand, in order to form the permanent magnet stopper 114 on both sides of the back yoke 113, all four molds need to be provided to be movable. In other words, a four-stage mold needs to be used. In this case, there is a fear that the mold cost is increased, and the overall wheel manufacturing cost is increased.

In order to reduce such an increase in mold cost, the following embodiments may be presented.

8 to 9, another embodiment and a manufacturing method of the wheel 110 will be described in detail.

This embodiment is very similar to the above-described embodiment. However, it can be said that the permanent magnet stopper 114 is formed only on one side of the back yoke 113.

Therefore, only one step 116 may be formed through the permanent magnet stopper 114. However, the coupling position of the permanent magnet can be easily determined through the permanent magnet stopper 114. This is because the permanent magnets 115 may be brought into close contact with the inner surface of the step 116, that is, the stopper 114, to couple the permanent magnets.

Through such a permanent magnet stopper 114, the wheel can be manufactured through a three-stage mold as shown in FIG.

That is, the upper and lower molds 160 and 161 and the outer mold 162 are provided to be movable. However, the inner mold 160 may be fixed. This is because the wheel can be removed from the mold upwards even if the inner mold is fixed based on FIG. 10.

Therefore, the wheel formation, the back yoke coupling, and the formation of the permanent magnet stopper may be simultaneously implemented through the three-stage mold rather than the four-stage mold. This makes it possible to significantly reduce the mold cost.

Meanwhile, in the above-described embodiments, the protruding height of the permanent magnet stopper 114, that is, the height protruding in the radial direction based on the radially inner surface of the back yoke may be variously selected. However, the protruding height is preferably formed to correspond to the thickness of the permanent magnet to be attached.

That is, the protruding height of the permanent magnet stopper 114 is formed so that the permanent magnet stopper 114 completely surrounds one end of the permanent magnet. In other words, the permanent magnet stopper 114 is preferably protruded by the thickness of the permanent magnet 115. Through this, the area in which the permanent magnet is coupled to the wheel 110 and the back yoke 113 may be maximized.

In order to improve the performance of the motor, how to configure the stator together with the rotor or wheel is very important. In particular, it can be very important how to wind the coil configured in the stator.

In general, for 36 teeth, many series concentrating windings are made. The central winding means that one coil is wound around one tooth to form one coil per tooth. In the case of the three-phase winding, it means that one end of the coil of u phase is connected to the u-phase power supply and the coil end is connected to the neutral point after forming 12 coils. That is, it means that all the coils forming one phase are connected in series with each other. In general, when a u phase is wound around one tooth, coils are formed in such a way that a v phase is wound on the next tooth and a w phase on the next tooth.

The applicant has proposed a winding method for enhancing the efficiency of the motor through the invention described in Republic of Korea Patent Application No. 10-2012-0000245 (filed Jan. 11, 2012, hereinafter 'suggested invention'). Accordingly, specific embodiments of the proposed invention may be combined with embodiments of the present specification unless they contradict or be exclusive to the embodiments herein.

Specifically, in the embodiment of the present invention, the number of teeth of the stator may be 36, and the number of poles of the wheel through the permanent magnet may be 40. In addition, every three neighboring teeth may be wound in one and the same phase (for example, u phase). That is, as in the conventional winding method, the u, v and w phases may not be sequentially wound every one tooth, but the u, v and w phases may be sequentially wound every three teeth.

According to the proposed invention, by winding the u, v and w phase every three teeth, it was possible to expect a significant improvement in the performance of the motor and reduction of cogging torque than the conventional. Therefore, if the winding method or the stator having the coils wound by the winding method is applied to the embodiments of the present invention, a significant performance improvement and a reduction in cogging torque can be expected.

On the other hand, in the conventional winding method and the proposed invention, as described above, the coils are formed in the series concentrated winding method. That is, the u phase power applied through the power terminal based on the u phase may be connected in series to the neutral point through the u phase coils. In other words, the coils forming the u phase are all connected in series. In simple terms, it can be said that the u phase is formed by one continuous line. The same applies to the v and w phases.

Therefore, the winding method of the motor in the above-described embodiment of the present invention may be basically made of a conventional series intensive winding, and the winding may be made in the same manner as the proposed invention. In the latter case, the coil is formed in three neighboring teeth on the u phase, and the coil is wound around the three neighboring teeth again after crossing the six teeth. In this way, a total of 12 u-phase coils may be formed when the number is 36 teeth. It can be expected that the motor efficiency and cogging torque reduction effect by this method is very remarkable.

This series connection can cause a problem that a large force cannot be used when a low voltage is applied.

In the case of an electric bike motor, a constant voltage may be applied through a battery or the like. However, there is a limit in increasing the battery voltage because there is a limit in the battery capacity due to the characteristics of the electric bike. In addition, the resistance of the wire itself cannot be ignored because the length of the wire forming the coil from the power supply terminal to the neutral point is very long. In other words, even if a constant voltage is applied due to the resistance of the wire itself, the strength of the current is inevitably reduced. Thus, in the case of an electric bike motor, a parallel winding, rather than a series winding, needs to be made.

In this embodiment, it is possible to provide an electric bike motor with a parallel winding.

In this case, the parallel winding is based on the number of 36 teeth and the u phase. The u phase coil (first sub coil) wound on six teeth and the u phase coil (second sub coil) wound on six other teeth are described. ) Are connected in parallel to each other. Thus, one end of the first and second sub coils is connected to the u-phase power supply terminal and the ends of the first and second sub coils form a neutral point. Thus, the line length between the power supply terminal and the neutral point can be reduced by half. Therefore, it is possible to use a large force at a constant voltage through the parallel winding rather than the series winding.

In this case, the parallel winding may be wound by a conventional method when forming a coil of each phase, or may be wound by the proposed method. That is, for example, the first sub coil may be made by a conventional method or a proposed method.

In either case, however, six wires are required to form a three-phase coil, one end of the six wires must be connected to the power supply terminal, and the other end of the six wires must be connected to the neutral terminal. Can be. In other words, the wiring process is required at a total of 12 places to form a coil in one stator, which is very complicated. This can also cause insulation problems between the lines that make up each phase.

Hereinafter, the winding method, that is, the manufacturing method of the motor, which can easily solve the connection processing problem will be described in detail. In addition, the structure of the motor, in particular the insulator structure that can easily implement this method will be described in detail.

First, a winding method according to an exemplary embodiment of the present invention will be described with reference to FIG. 10. In particular, the parallel winding will be described in detail.

FIG. 10 illustrates an example in which one phase coil is formed on one tooth and 36 coils are formed for convenience of description, and coils forming one phase are connected in parallel.

First, the u-phase coils will be described, and the remaining v-phase and w-phase coils are formed in the same manner, and thus detailed description thereof will be omitted.

The u phase may include the first sub coil S1 and the second sub coil S2. The first sub coil and the second sub coil are connected in parallel. The first sub coil S1 starts at one end u1a and continues to the other end u1b. Similarly, the second sub coil S2 starts at one end u2a and continues to the other end u2b.

Here, one end u1a of the first sub coil S1 and one end u2a of the second sub coil S2 are fixed to the u power terminal, and the other end u1b and the second end of the first sub coil S1 are fixed. The other end u2b of the sub coil S2 is fixed to the neutral terminal.

Each of the tooth coils S11 to S26 constituting the first sub coil S1 and the second sub coil S2 may be formed to sequentially cross two teeth as in the conventional winding method. However, as described above, it is preferable to form the same as the proposed invention.

Specifically, the S11 coil, the S12 coil, and the S13 coil may be formed in three consecutive teeth, and thereafter, the S14 coil, S15 coil, and S16 coil may be formed in three consecutive teeth across the six teeth. That is, the first sub coil S1 may be formed in this manner. Here, the winding direction of each tooth coil in three consecutive teeth is preferably opposite to each other. And this pattern is preferably repeated regularly.

The second sub coil S2 may be formed from six teeth across the S16 coil. In the same manner, the S21 tooth coil to the S26 tooth coil may be formed. That is, S21, S22, and S23 are formed in three consecutive teeth, and then S24, S25, and S26 tooth coils may be formed in three teeth again after crossing the six teeth.

In this way coils on u can be formed. That is, a first sub coil having a u phase is formed, and a second sub coil having the same u phase as the first sub coil and connected in parallel is formed. Therefore, the first sub coil and the second sub coil may be formed symmetrically with respect to the center of the stator.

In the same manner, coils on v and coils on w may be formed. Similarly, the coil on v may include a third sub coil S3 and a fourth sub coil S4, and the coil on w may include a fifth sub coil S5 and a sixth sub coil S6. have. Of course, each sub coil may comprise six tooth coils each.

After forming the coils on u, v, and w in the above-described manner, the ends of the lines constituting each phase should be connected. That is, the ends must be fixed for the power connection and the neutral point formation.

First, one ends u1a, u2a, v1a, v2a, w1a, and w2a of each of the sub coils S1 to S6 are connected to a power supply terminal. That is, u1a and u2a, one end of u phase, are fixed to the u phase power supply terminal, v1a and one end of v phase, v2a are the v phase power supply terminal and w1a and w2a, one end of the w phase.

The other ends u1b, u2b, v1b, v2b, w1b, and w2b of each of the sub coils S1 to S6 are fixed to the neutral terminal.

The neutral terminal may have six terminals electrically connected to each other at one terminal, and six terminals may be electrically connected to each other through three terminals. For example, u1b and u2b, v1b and v2b, and w1b and w2b may be fixed to the u phase neutral point, the v phase neutral point, and the w phase neutral point terminal, respectively. Each neutral terminal may be electrically connected to each other.

Therefore, coil formation and electrical connection of the stator are made through the above-described method.

Hereinafter, a detailed wiring method will be described in detail with reference to FIGS. 11 and 12.

11 shows an insulator 170 of a stator. The insulators may be coupled to each other by being provided up and down or left and right, respectively, and the insulators may be integrally formed on the stator through insert injection. That is, after the stator core is inserted into the mold, the insulator may be integrally formed on the stator through injection. Thus, the stator may comprise an insulator.

The insulator shown in FIG. 11 may be referred to as an upper insulator 170 for convenience of description. That is, it is a structure provided in the upper part of a stator. Accordingly, although not shown, a lower insulator provided under the stator may be included.

The insulator 170 is configured to cover the stator core 141 and the teeth 142. Specifically, a coil is wound on the insulator 170.

The insulator 170 may include a winding part 171 to which the coil is wound and a moving part 172 provided inside the radial direction of the winding part and to which the coil ends move. In addition, a circumferential rib 173 may be formed to partition the inside of the stator from the coil or the leader lines.

The circumferential rib 173 is formed substantially in the circumferential direction and may protrude upward. Coil hook 175 to be described later may also protrude upward. The circumferential rib 173 or coil hanger 175 substantially forms the top of the stator. Of course, it can be said that when these structures are formed on the lower insulator, they substantially form the bottom of the stator.

Accordingly, the coil or the leader line may not be damaged through the circumferential rib 173 or the coil hanger 175. This is because the coil or the leader wire does not contact the bottom surface when the stator is handled, and the circumferential rib or coil hook may directly contact the bottom surface.

The winding part 171 corresponds to each tooth and is positioned above and below the tooth to perform an insulation function between the tooth and the coil. Of course, a coil is formed in the winding part 171.

11 shows an insulator 170 in which 36 windings are formed in accordance with the number of 36 teeth. As shown, the specific teeth or windings may be referred to as t1, and the respective teeth or windings may be sequentially called t2 to t36 along the counterclockwise direction.

For convenience of explanation, it is assumed that the aforementioned first sub coil starts at t1.

S11 tooth coils can be formed clockwise at t1, S12 tooth coils counterclockwise at t2 and S13 coils clockwise at t3. Then, after forming the S13 coil, it is possible to form S14 in the clockwise direction at t10 and S15 in the counterclockwise direction at t11 and S16 at t12 after crossing the six teeth or the winding part. Like the first sub coil, a second sub coil is formed through t19, t20, t21, t28, t29, and t30. In this way, a u-phase coil is formed.

To form the v-phase coil, a third sub coil is formed at t4, t5, t6, t13, t14 and t15, and a fourth sub coil is formed at t22, t23, t24, t31, t32 and t33. To form the w phase coil, a fifth sub coil is formed at t7, t8, t9, t16, t17 and t18 and a sixth sub coil is formed at t34, t35 and t36.

Here, insulation between neighboring coils having the same phase as each other, for example, insulation between S11 and S12 may be a problem. Insulation between the connecting line that is long and extended from S13 to S14 may be problematic. In addition, insulation between the connection line for connecting u1a to the u-phase power terminal and other connection lines may be problematic.

Of course, the above problems are the same for the v phase and the w phase as well as the u phase, and insulation may be a problem between the respective phases. In addition, the insulation of the connection lines at the ends of each sub-coil for the neutral connection may also be a problem.

Here, the lead line means lines exposed on the insulator for connection or connection between each coil except for coils formed on the winding unit 171. Thus, the lead wire includes a power supply line or a coil connection line.

In this embodiment, since the three-phase parallel connection is made, in particular, the power supply line processing may be a problem.

Hereinafter, a method and a structure for solving the insulation problem of the leader line will be described in detail.

First, a coil hook 175 may be formed to process a connection line between each tooth coil and the tooth coil. The coil hook 175 may correspond to each of the winding parts 171, and may be formed to protrude upward in a radial direction of the winding part.

Coil ribs 177 may be formed between the coil hooks 175. The coil rib 177 may be omitted. That is, the formation and omission of the coil rib along the circumferential direction can be repeated. In addition, the coil rib 177 may form a gap with the coil hook 175, and the size of the gap may vary. In other words, the pattern of varying the size of the gap may be repeated along the circumferential direction. For example, the size of the gap may be maximized by omitting coil ribs. In addition, since the leader line or the connection line is positioned on the coil rib 177, it is possible to form a height difference with the moving unit 172.

In FIG. 12, the omitted coil rib 177b, the large gap coil rib 177a, and the small gap coil rib 177 are repeatedly formed along the circumferential direction. The gap here means the circumferential distance between the coil hanger and the coil rib.

A coil gap 177a having a large gap is formed on the right side of the omitted coil rib 177b based on the coil hanger 175 corresponding to t2. In addition, a coil rib 177 having a small gap is illustrated on the right side of the coil hanger 175 corresponding to t3.

Due to the presence and absence of the coil ribs and the repeating pattern of the shape, it is possible to secure the insulation distance of the connecting line connecting from one tooth to the neighboring teeth and the insulation distance of the connecting line connecting from one tooth to six teeth.

For example, the connecting line from t3 to t10 is on the coil distance 175 corresponding to t10 and the coil rib 177 on the left from the gap between the coil distance 175 corresponding to t3 and the coil rib 177 on the right. Leads to. Therefore, left and right height difference may occur. By using the height difference, an insulation distance between the connection lines may be secured.

The tooth coil S11 may be formed in a clockwise direction at t1. One end u1a of the first coil is fixed to the groove 181b of the u-phase terminal 181 after forming S11. That is, it is fixed to the u-phase terminal to be in contact with the moving part 172 along the right side of the coil hanger 175 corresponding to t1.

In addition, the leader line at S11 continues to t2 in the state of being positioned on the left coil rib 177 of the coil hanger 175 to form the tooth coil S12. Since the leader line is located on the coil rib 177, an insulation distance with the u1a leader line positioned in the moving unit 172 may be ensured. Of course, the power terminal and the neutral terminal will be preferably provided in the radially inner side as compared to the coil hanger.

Thereafter, S12 may be formed counterclockwise at t2 and S13 clockwise at t3. Of course, even in this case, the leader line may be formed using the respective coil hangers 175.

Here, although the leader line is formed long from t3 to t10, it is necessary that such a leader line has an insulation distance from the leader line of another phase. To this end, a leader line may be formed from the lower left side of the coil hanger 175 corresponding to t3 to the left coil rib 177 of the coil hanger 175 corresponding to t10. That is, the leader line may be formed in a form in which the height increases gradually from the left to the right. In other words, the leader line may be formed upward.

This may be referred to as using the left and right height difference due to the coil rib 177. It is possible to form such height difference by using the coil rib on the right side and not using the coil rib on the left side.

Similarly, the v phase forms such leader line from t6 to t13 and the w phase forms such leader line from t9 to t16. As a result, these lead wires may be formed in the shape of a right upward diagonal line, so that an insulation distance from each other may be maintained.

Meanwhile, at t4, one end of the v-phase v1a is moved clockwise along the moving unit 172 and then fixed to the v-phase power terminal 182. Similarly, at t7, the w phase one end w1a is also moved clockwise along the moving unit 172 and then fixed to the w phase power terminal 183.

Here, insulation between u1a, v1a, and w1a to be connected to the power supply terminal 180 may be a problem.

The moving part 172 needs to be sufficiently formed so that three lead wires of radial width may have an insulation distance from each other. If necessary, circumferential grooves (not shown) having different radii may be formed. In addition, if necessary, a stepped portion 174 may be formed to ensure an insulation distance between the lead lines of the respective phases.

For example, the radially inner side of the moving part needs to be provided such that the leader line on w, the leader line on w, and the leader line on u are radially outward. In order to determine this position, the above-described circumferential groove or step 174 may be formed. Of course, the opposite is also possible.

The leader line of each phase moving along the moving part needs to have a height difference between the power terminals 180. When u1a is fixed to the u-phase power supply terminal 180 through the bottom of the moving part 172, the ends v1a and w1a of the other leader line need to be fixed to the power supply terminals of the v-phase and w-phase at an increasingly higher position.

For this purpose, the operator needs to apply tension to the ends of the leader lines, and for this purpose, it is preferable that a plurality of protrusions 176 are formed on the radially outer side of the power terminal 180.

The operator may change direction while simultaneously applying tensile force to the leader lines through the protrusion 176. And, the height of the leader lines can be changed. Therefore, the height difference between the terminals u1a, v1a, and w1a of each phase may be formed in the power supply terminal 180, thereby ensuring an insulation distance.

On the other hand, the power terminal 180 is formed with fixing grooves (181b, 182b, 183b) to which the lead wires are caught. After the leader lines are fixed to the fixing grooves, a magmate (not shown) is inserted into the receiving parts 181a, 182a, and 183a.

Magmate is a kind of connector that is inserted into the receiving portion and at the same time refers to a connector that is electrically connected by peeling the coating of the wire. Since the magmate is a configuration obvious to those skilled in the art, detailed description thereof will be omitted.

Here, the position of the fixing groove may vary depending on each phase. That is, the position of the fixing groove may be changed so that the position where the end is fixed depends on each phase. For example, the position of the fixing groove 183b in the w-phase power terminal may be the highest, and the position of the fixing groove 181b in the u-phase power terminal may be the lowest. Due to the position difference between the fixing grooves it may be easy to secure the insulation distance. Of course, in this case, the protrusion 176 may be formed.

Meanwhile, since the coils of the phases are connected in parallel, one end u2a of the second coil, one end v2a of the fourth coil, and one end w2a of the sixth coil are also fixed to the power supply terminal 180.

Specifically, the one end coil u2a at t19 moves in the counterclockwise direction through the moving unit 172. One end of the coil v2a at t22 and one end of the coil w2a at t25 also move counterclockwise to be fixed to the power supply terminal 180.

As described above, the leader lines due to the movement may maintain the insulation distance from each other due to the sufficient radial width of the moving unit 172. In addition, the insulation distance may be maintained in the vicinity of the power terminal 180 through the height difference of the protrusion 176 or the fixing groove.

In the above, the method and structure of maintaining the insulation distance between the tooth coil and the tooth coil and maintaining the insulation distance between the lead wires for power connection have been described in detail.

Hereinafter, a method and a structure of maintaining an insulation distance between lead wires for connecting a neutral point will be described in detail.

As described above, the leader lines for power connection are moved through the moving unit 176. Accordingly, the lead wires may be said to maintain an insulation distance through the moving part 176 of the upper insulator.

Six connections are also required for neutral connection. The lead wires for the neutral point connection are preferably maintained at an insulation distance through the moving part of the lower insulator.

That is, it is preferable that a lower insulator is provided that is substantially the same as the upper insulator shown in FIGS. 11 and 12. Similarly, a coil hook 175 may be provided in the lower insulator. In addition, the moving part 172 and the circumferential groove or step portion of the moving part may be provided in the lower insulator. Of course, the power terminal 180 may be provided in the upper insulator.

An end of the t12 coil S16, that is, an end u1b of the first sub coil is moved counterclockwise along the moving part of the lower insulator and is fixed to the neutral terminal 190. Similarly, the end of the t15 coil S36, that is, the end v1b of the third sub coil and the t18 coil S56, that is, the end w1b of the fifth sub coil, also move counterclockwise to the neutral terminal 190. It is fixed.

The ends of the second sub coil, the fourth sub coil, and the sixth sub coil move in a clockwise direction and are fixed to the neutral terminal 190.

 Thus, the neutral terminal 190 may be provided in the lower insulator, unlike in FIG. 11.

If the neutral terminal 190 is provided in the upper insulator as shown in Fig. 11, the ends u1b, v1b, w1b are connected from the lower insulator to the upper insulator through the slot, i.e. the space between the teeth and the teeth. After being moved, it may be fixed to the neutral terminal 190.

Here, since six connections are made in the neutral terminal 190, the structure may be complicated, and the height of the neutral terminal 190 may be significantly increased. This may increase the height of the stator as a whole.

Therefore, the neutral point terminal 190 may include a u-phase neutral terminal 191, a v-phase neutral terminal 192 and a w-phase neutral terminal 193 so that the neutral points of each phase are connected.

The other end u1b of the first sub coil and the other end u2b of the second sub coil may be fixed to the u-phase neutral terminal 191. That is, only two wires may be formed in one terminal 191, 192, and 193. Then, six wirings can be made at once by inserting one magmate into three terminals. Thus, the six lines are electrically connected to each other through one magmate to form a neutral point. Therefore, neutral point formation is very easy and simple.

Here, the structure of the neutral terminal 190 and the structure of the vicinity thereof may be similar or identical to those of the power terminal described above. That is, the height difference or protrusion configurations of the grooves can be implemented as well.

As described above, the lead wires for power connection are arranged through the moving part of the upper insulator, and the lead wires for the neutral point connection are arranged through the moving part of the lower insulator. Therefore, it is easy to secure the insulation distance of the leader lines and arrangement of the leader lines becomes very easy.

In addition, through the configuration of the coil hanger, coil ribs, protrusions, etc., the connection is very easy, it is easy to secure the insulation distance between the connections. Thus, it becomes possible to provide a motor with improved reliability.

On the other hand, the coil hook 175 described above may be formed in a double. That is, the step 175 may be formed. Using the step 175, the wiring process may be easy. For example, it may be possible to form a height difference between the leader lines using the step 175 near the power terminal or near the neutral terminal.

100: motor 110: wheel
113: back yoke 114: permanent magnet stopper
115: permanent magnet 120: motor cover
130: shaft 140: stator
170: insulator 171: winding part
172: moving part 173: circumferential rib
175: coil hook 176: protrusion
177: coil rib 180: power terminal
190: neutral terminal

Claims (20)

In the electric bike motor for driving the wheels of the electric bike,
A wheel connected to the wheel;
A back yoke provided at an inner side in the radial direction of the wheel;
A permanent magnet provided in the radially inner side of the back yoke;
A permanent magnet stopper formed integrally with the wheel and protruding radially inward longer than the thickness of the back yoke to determine a position at which the permanent magnet is provided; And
An electric bike motor comprising a stator provided inside the permanent magnet. The method of claim 1,
The permanent magnet stopper is provided on each side of the back yoke, the electric bike motor. The method of claim 1,
The permanent magnet stopper is an electric bike motor, characterized in that provided on the left or right side of the back yoke. The method of claim 1,
The wheel,
A wheel case formed in an annular shape to form the center of the wheel; And
And a wheel hub extending radially outwardly from each side of the wheel case and integrally formed with the wheel case. 5. The method of claim 4,
And a motor cover coupled to both sides of the wheel case to rotate integrally with the wheel case. 5. The method of claim 4,
The wheel is an electric bike motor, characterized in that formed to surround all except the radially inner surface of the ring-shaped back yoke. The method according to claim 6,
The permanent magnet is attached to the radially inner surface of the back yoke through an adhesive. The method according to claim 6,
The permanent magnet is attached to the radially inner surface of the back yoke and the inner surface of the permanent magnet stopper through an adhesive. The method according to claim 6,
And the back yoke is coupled to the wheel at the same time as the wheel is formed through casting while the back yoke is inserted into a mold. The method of claim 1,
And a plurality of coils having three phases are wound around the plurality of teeth of the stator, and the coils of each phase are connected in parallel. 11. The method of claim 10,
The number of teeth is 36 in the circumferential direction, characterized in that the coil of the same phase is wound every three neighboring teeth. The method of claim 11,
The number of poles of the permanent magnet is an electric bike motor, characterized in that 40 in the circumferential direction. 13. The method of claim 12,
The number of the permanent magnet is 10, the electric bike motor, characterized in that one permanent magnet has four poles along the circumferential direction. 11. The method of claim 10,
Coils of the same phase are wound around three neighboring teeth and three neighboring teeth again, and a first sub coil is formed, and a second sub coil is symmetrically connected to the first sub coil. Electric bike motor. 15. The method of claim 14,
One end of the first and second sub coils is fixed to a power terminal on u, and the other end of the first and second sub coils is fixed to a neutral terminal. The method of claim 15,
One end of the sub coil is fixed to the power terminal after being moved along the circumferential direction of one side of the stator, the other end of the sub coil is fixed to the neutral point terminal after being moved along the circumferential direction of the other side of the stator Electric bike motor. Inserting a back yoke having a ring shape of a ferromagnetic material into a mold; And
And a wheel manufacturing step of forming a wheel connected to the wheel of the electric bike at the radially outer side of the back yoke through casting or injection, and simultaneously coupling the back yoke to the wheel.
In the wheel manufacturing step,
The permanent magnet stopper is formed integrally with the wheel and protrudes inward in a radial direction longer than the thickness of the back yoke, thereby determining a coupling position of the permanent magnet coupled to the radially inner surface of the back yoke. Method of manufacturing an electric bike motor. The method of claim 17,
The wheel is a manufacturing method of an electric bike motor, characterized in that formed to surround all except the radially inner surface of the back yoke. The method of claim 17,
The permanent magnet stopper is a method of manufacturing an electric bike motor, characterized in that formed on one side or both sides of the back yoke. The method of claim 17,
The permanent magnet is a method of manufacturing an electric bike motor, characterized in that attached to the inner surface of the radially inner surface of the back yoke and the permanent magnet stopper via an adhesive.

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