TWM573101U - Stator of brushless motor - Google Patents

Abstract

A stator of a brushless motor includes a stator core, a first bobbin, a second bobbin, a winding unit, and a shorting unit. The stator core includes a yoke portion extending along an axis and six pole portions protruding from an inner side of the yoke portion. The axis is defined to extend in an axial direction. The first bobbin includes a substrate abutting the stator core in the axial direction, and a stepped class protruding in the axial direction from the substrate and staggered in the axial direction about the axis. The winding unit includes three coil groups, each coil group includes two coil portions wound around the two pole portions, and a connecting portion and two free ends connected to the coil portions and disposed around the outer side of the surrounding member. The shorting unit is disposed on the first bobbin and is electrically connected to the three power lines, and the shorting unit clamps the connection portion and the free end of the coil groups and is electrically connected to the coil groups. By virtue of the structure of the wrap-around class, the present invention facilitates the use of an automated machine such as a winder or a spot welder to facilitate automated production.

Description

Stator of brushless motor

The present invention relates to a stator, and more particularly to a stator of a brushless horse.

A stator of a brushless motor disclosed in Chinese Patent Publication No. CN104426274, the stator comprising a stator core, a front insulator disposed on a front end surface of the stator core, and a rear end surface disposed on the stator core a rear insulator, six coils wound around the stator core, six winding wires respectively connected between adjacent two coils, six pressure welding terminals interposed in the front insulator and respectively holding the coil wires, a sensor circuit substrate disposed on the front insulator, and a short-circuiting member disposed on the front insulator, the short-circuiting member having three sheet metal parts respectively spot-welded with three power lines (U phase, V phase, W phase), Each sheet metal member has a semicircular shape around an axis of the stator core, and each sheet metal member has two shorting fins at both ends of the semicircular shape, and the sheet metal members are stacked at intervals along the axis and are angled around the axis Interleaved, the shorting pieces of the sheet metal parts are respectively soldered to the pressure welding terminals.

Although such a stator is manufactured, a wire can be sequentially wound around the teeth of the stator core to form the coils, but each of the two opposite coils is not connected, so that the sheet metal components need to be additionally bridged. However, in general, the stator has opposite coils to be separately provided with the problem of the adapter cable or the adapter plate, which increases the complexity of the structure and the manufacturing process, and the pressure welding terminals of the stator and the short circuit pieces. It is not easy to use automatic spot welding of the machine, and only the delta type wiring state can be formed after the stator is made. If the Y type wiring state is to be formed, the winding method of the wire must be changed to form different winding structures and short circuit parts. The structure, which will not be conducive to automated production.

Therefore, the object of the present invention is to provide a stator for a brushless motor that facilitates automated production.

Therefore, the stator of the novel brushless motor is suitable for connecting three power lines, the stator of the brushless motor comprises a certain sub-core, a first bobbin, a second bobbin, a winding unit, and a Short circuit unit.

The stator core includes a yoke portion that is hollow cylindrical and extends along an axis, and six pole portions that are symmetrically disposed about the axis and protrude from the inner circumferential surface of the yoke portion toward the axis, and along a first end surface and a second end surface opposite to the axis.

The first bobbin is disposed on the first end surface of the stator core, the first bobbin includes a substrate that is annular around the axis and abuts the first end surface, and a surrounding class disposed on the substrate The substrate has a first surface opposite to the axis and a second surface. The second surface abuts the first end surface, and the axis is defined to extend along an axial direction. The surrounding structure is protruded along the axial direction. a first surface of the substrate and a column-like shape in which the axis is high and low in the axial direction.

The second bobbin is disposed on the second end surface of the stator core.

The winding unit includes three coil groups respectively wound around two opposite pole portions of the stator core, each coil group including two coil portions wound around the respective pole portions, and one coil portion electrically connected And connecting outwardly to the connecting portion outside the surrounding class, and two electrically connecting the coil portions and outwardly winding around the free end of the surrounding class, the connecting portion and the free end of the coil group spanning the The surrounding class extends to the outside of the surrounding class, and the connecting portions and the free ends are located at different positions in the axial direction with respect to the stator core.

The short-circuiting unit is disposed on the first bobbin and is configured to electrically connect the power cables, and the short-circuiting unit clamps the connecting portions of the coil groups and the free ends, and the portion of the short-circuiting unit is selectable The ground is thermally fused to be electrically connected to the coil sets. .

The utility model has the advantages that: the winding unit of the first bobbin is in a high-low staggered class shape in the axial direction, so that the winding unit can be wound around the wire during the automatic winding manufacturing process of the machine. Positioned outside the stator core, so that the winding can be completed by only one wire, and the connecting portions and the free ends wound around the outer side of the surrounding class are located at different positions in the axial direction to facilitate the short-circuiting unit. The clamping and hot melt.

Referring to FIG. 1 and FIG. 2, an embodiment of the stator of the novel brushless motor is suitable for connecting three power lines 7 and is used with a Hall plate holder 8 and a Hall plate 9. The stator 1 of the brushless motor is used. The stator core 2, a first bobbin 3, a second bobbin 4, a winding unit 5, and a shorting unit 6 are included.

The stator core 2 includes a yoke portion 21 which is hollow and extends along an axis L, six symmetrical about the axis L, and protrudes from the inner circumferential surface 211 of the yoke portion 21 toward the axis L The pole portion 22 and a first end surface 23 and a second end surface 24 disposed opposite to each other along the axis L define the axis L to extend along an axial direction D.

Referring to FIG. 2 to FIG. 4 , the first bobbin 3 is disposed on the first end surface 23 of the stator core 2 and fits the pole portion 22 , and the first bobbin 3 includes a circle L around the axis L. a substrate 30 that is annularly connected to the first end surface 23, and a surrounding member 31 disposed on the substrate 30. The substrate 30 has a first surface 301 and a second surface 302 opposite to each other in the axial direction D. The second surface 302 abuts the first end surface 23, and the surrounding surface 31 protrudes from the first surface 301 of the substrate 30 along the axial direction D, defining a circumferential direction R around the axis L. The circumferential direction R is sequentially arranged and respectively corresponds to a first portion 310, a second portion 320, a third portion 330, a fourth portion 340, a fifth portion 350, and a sixth portion of the equipotential portion 22. Part 360. The first portion 310 has a first step group 311 and a first bump group 312. The second portion 320 has a second step group 321 and a second bump group 322. The 330 has a third step group 331 and a third bump group 332. The fourth portion 340 has a fourth step group 341 and a fourth bump group 342. The fifth portion 350 has a first portion. a fifth-order surface group 351, and a fifth bump group 352, the sixth portion 360 has a sixth-order surface group 361, and a sixth bump group 362, the first, second, third, fourth The fifth and sixth step groups 311, 321, 331, 341, 351, 361 are connected between the inner side and the outer side of the wraparound class 31, the first, second, third, fourth, fifth, and Six bump groups 312, 322, 332, 342, 352, 362 are respectively protruded along the axial direction D in the first, second, third, fourth, fifth and sixth step groups 311, 321, 331 , 341, 351, 361. The first step group 311 and the fourth step group 341 of the first bobbin 3 are closer to the stator core 2 in the axial direction than the second step group 321 and the fifth step group 351. The third step group 331 and the sixth step group 361 are away from the stator core 2 in the axial direction D compared to the second step group 321 and the fifth step surface 351 group.

In detail, in the embodiment, the first portion 310, the second portion 320, and the third portion 330 are similar in structure, and the fourth portion 340, the fifth portion 350, and the sixth portion 360 are similar in structure. , but not limited to this. The first step group 311 of the first portion 310 has a step a (see FIG. 4), and the first block group 312 has two protrusions respectively on opposite sides of the step a along the circumferential direction R. The bump b (see FIG. 4), and the structure of the second portion 320 and the third portion 330 are deduced by analogy. The fourth step group 341 of the fourth portion 340 has two step faces c (see FIG. 4) spaced along the circumferential direction R, and the fourth bump group 342 has a protrusion on the step c. And the bumps d (see FIG. 4) between the step faces c, and the structures of the fifth portion 350 and the sixth portion 360 are deduced by analogy.

The second bobbin 4 is disposed on the second end surface 24 of the stator core 2 and fitted to the pole portions 22 .

Referring to FIG. 2 and FIG. 5, the winding unit 5 includes three coil sets 51 respectively wound around the opposite pole portions 22 of the stator core 2, and each coil group 51 includes two windings on the respective poles. The coil portion 511 of the portion 22 is electrically connected to the coil portions 511 and The connecting portion 512 is disposed outside the surrounding portion 31, and the second connecting portion 511 is electrically connected to the coil portion 511 and outwardly disposed at a free end 513 outside the surrounding portion 31. The connecting portion 512 and the free end 513 span the corresponding first, second, third, fourth, fifth and sixth step groups 311, 321, 331, 341, 351, 361 by The first, second, third, fourth, fifth, and sixth bump sets 312, 322, 332, 342, 352, and 362 are disposed around the wraparound section 31 along the circumferential direction R, and the same The connecting portion 512 and the free end 513 are opposite to the stator core 1 by the first, second, third, fourth, fifth, and sixth step groups 311, 321, 331, 341, 351, and 361 The axial direction D is at different positions.

Referring to FIG. 5 to FIG. 7 , the short circuit unit 6 includes three first short circuit pieces 61 and a second short circuit piece 62 which are spaced apart from the first winding frame 3 around the axis L. The first short circuit pieces 61 are used. Each of the first short-circuiting strips 61 has a fixed section 611 fixed to the first bobbin 3, and is connected to the fixed section 611 and clamped together with the fixed section 611. a clamping section 612 of the winding unit 5, each clamping section 612 has a first hot melt portion 613 that clamps the connecting portion 512 of one of the coil sets 51, and two of which clamp the other coil group 51 respectively The second heat-melting portion 614 of the free end 513, and the first short-circuiting pieces 61 are respectively pressed by the coil sets 51 of different combinations. The second short circuit piece 62 has a fastening portion 621 fixed to the first bobbin 3, and a clamping portion 622 that connects the fastening portion 621 and clamps the winding unit 5 together with the fixing portion 621. The clamping section 622 has three third hot melt sections 623 that respectively clamp the connecting portions 512 of the coil sets 51. At least six of the first hot melt portion 613, the second hot melt portion 614, and the third hot melt portion 623 are thermally fused to be electrically connected to the coil groups 51.

Referring to FIG. 8, when the short-circuiting unit 6 is thermally melted, one of the second hot-melt portions 614 of each of the first short-circuiting pieces 61, and the third hot-melting portions 623 of the second short-circuiting pieces 62, The stator 1 is in the state of a Y-string connection line.

Referring to FIG. 9, when the short-circuiting unit 6 is thermally melted, the second hot-melt portion 614 of each first short-circuiting piece 61, and the third hot-melting portions 623 of the second short-circuiting pieces 62, The stator 1 has a Y shape and is connected to a wire state.

Referring to FIG. 10, when the short-circuiting unit 6 is thermally melted, the first hot-melt portion 611 of each first short-circuiting piece 61 and a second hot-melting portion 612 thereof are in a delta-type string connection state. .

Referring to FIG. 11, when the short-circuiting unit 6 is thermally melted, the first hot-melt portion 611 and the second hot-melt portion 612 of each first short-circuiting piece 61 are in a delta-type and connected state. .

Referring to FIG. 12, the stator of the brushless motor of the present embodiment can be sequentially formed through a preparation step S0, a winding step S1, a short-circuit unit setting step S2, a trimming step S3, and a conducting step S4.

Referring to FIG. 13 and FIG. 14 , the preparation step S0 is to prepare a stator 1 of a brushless motor that has not been wound, and the stator 1 includes a stator core 2 , a first bobbin 3 , and a second bobbin 4 . And a short circuit unit 6. Wherein, the stator core 2, the first bobbin 3, and the second bobbin 4 have no change in the structure before and after the manufacture, that is, the stator core 2, the first The structure of the bobbin 3 and the second bobbin 4 are the same as those described above, and thus the description thereof will not be repeated. The shorting unit 6 is disposed on the first bobbin 3 and is used to electrically connect the three power lines 7 (U phase, V phase, W phase). The shorting unit 6 includes three first shorting pieces 61 and a second shorting piece 62 spaced apart from the first winding frame 3 around the axis L, and the first shorting pieces 61 are respectively connected to the three power supply lines 7 Each of the first shorting pieces 61 has a fixing portion 611 fixed to the first bobbin 3, and a clamping portion 612 connecting the fixing portion 611 and extending away from the fixing portion 611, the second The shorting piece 62 has a fixing section 621 fixed to the first bobbin 3, and a clamping section 622 connecting the fixing section 621 and extending away from the fixing section 621.

Referring to FIG. 15 to FIG. 18, the winding step S1 is to wind an electrically conductive wire 500 around the outer circumference of the first bobbin 3 in the circumferential direction R, and the first bobbin is arranged in a winding sequence. 3, the outer side is wound inwardly on the pole portion 22 to form a winding unit 5, and the winding sequence is sequentially along the circumferential direction R from the first portion 310, the fourth portion 340, the second portion 320, and the fifth The portion 350, the third portion 330, and the sixth portion 360 are wound inwardly on the corresponding pole portion 22, and the wire 500 is wound outward to the first bobbin 3 after each of the pole portions 22 is wound. The outer side is wound in the circumferential direction R to the next pole portion 22 to be wound. The wire 500 is wound around the outer side of the first bobbin 3 in the circumferential direction R. (The arrows in FIGS. 15 and 16 are the winding directions of the wire 500, and FIG. 15 is the pole portion of the first portion 310 and the fourth portion 340 of the first bobbin 3 that has just been wound around the wire 500. 2 o'clock status)

In detail, in the embodiment, when the wire 500 passes between the inner side and the outer side of the first bobbin 3, the wire 500 is wound around the first, second, third, and fourth. And fifth and sixth step groups 311, 321, 331, 341, 351, 361, and via the first, second, third, fourth, fifth, and sixth bump groups 312, 322, and 332, 342, 352, 362 to switch the winding direction. Wherein, the first, second, third, fourth, fifth, and sixth step groups 311, 321, 331, 341, 351, and 361 are located at different positions along the axial direction D, so that the wire 500 is wound. The way is to gradually move away from the stator core 2 along the axial direction D.

After the winding is completed, the winding unit 5 has six coil portions 511 respectively wound around the pole portions 22, five connecting portions 512 respectively connected to the coil portions 511, and two respectively corresponding to the first portion 310. And the free end 513 of the coil portion 511 of the sixth portion 360, wherein the free ends 513 are the starting end I and the ending end II of the wire 500 when it is wound (as shown in FIGS. 16-18). . The connecting portions 512 and the free ends 513 are located at different positions in the axial direction D with respect to the stator core 2.

The short-circuiting unit setting step S2 is to fold the clamping section 612 and the clamping section 622 of the first short-circuiting piece 61 and the second short-circuiting piece 62 of the short-circuiting unit 6 so that the clamping section 612 and the clamping section 622 The fixing portion 611 and the fastening portion 621 are respectively adjacent to the connecting portion 512 and the free end 513 of the winding unit 5 (as shown in FIGS. 5-7).

The thread trimming step S3 is to cut the connecting portion 512 of the winding unit 5 between the fourth portion 340 and the second portion 320 to form two other free ends 513, and the cutting is disposed around the fifth portion 350 and the third portion. The connection portion 512 between the portions 330 forms the other two free ends 513. In addition, in this embodiment, the portion where the wire 500 starts and the end is too long is also cut.

Referring to FIGS. 5 to 7, after the cutting is completed, the winding unit 5 has six coil portions 511 wound around the pole portions 22, and three coil portions 511 respectively connected and wound around the opposite pole portions 22. The connecting portion 512 and the six free ends 513 respectively connecting the coil portions 511, and the two coil portions 511 which are opposite to the axis L and the one connecting portion 512 and the two free portions to which the coil portions 511 are connected The ends 513 are collectively defined as a coil group 51 (see FIG. 11) in which the connecting portion 512 and the free end 513 of one coil group 51 are located between the connecting portion 512 and the free end 513 of the other two coil groups 51 in the axial direction D. And the coil sets 51 do not directly contact each other. The nip portion 612 of each of the first shorting fins 61 of the shorting unit 6 has a first hot melt portion 613 that clamps the connecting portion 512 of one of the coil groups 51, and two crimps the other coil group 51 respectively. The second heat-melting portion 614 of the free ends 513, and the first short-circuiting pieces 61 respectively press the coil assembly 51 of different combinations, and the clamping portion 622 of the second short-circuiting piece 62 has three coils respectively clamping the coils The third hot melt portion 623 of the connecting portion 512 of the group 51.

The conducting step S4 is to thermally fuse the short-circuiting unit 6, and the portion of the short-circuiting unit 6 that is thermally melted is the first hot-melt portion 613, the second hot-melt portion 614, and the third hot-melt portion 623. At least six, so that the short-circuit unit 6 is electrically connected to the clamped coil group 51. In the embodiment, the conducting step S4 is to weld the shorting unit 6 to the winding unit 5 in a spot welding manner, and the enameled wire on the surface of the wire 500 is melted through during the spot welding to make the short circuit. The unit 6 is electrically connected to the winding unit 5.

The winding step S1, the short-circuit unit setting step S2, the trimming step S3, and the conducting step S4 can all be completed by an existing automatic machine (such as a winding machine, a spot welder, etc.). Through the above steps, the stator of the novel brushless motor can be fabricated.

Through the above description, the advantages of the stator of the novel brushless motor are summarized as follows:

1. The winding unit 3 of the first bobbin 3 is in the form of a high and low staggered shape in the axial direction D, so that the winding unit 5 can be used for wire winding in the process of automatically winding and manufacturing the machine. The 500 winding is positioned on the outer side of the first end surface 23 of the stator core 2, so that the winding is completed by only one wire, and the connecting portion 512 and the free end 513 wound around the outer side of the surrounding segment 31 are The axial direction D is located at different positions to facilitate the clamping and hot-melting of the short-circuiting unit 6 in the subsequent process.

2. By the position of the crimping connection between the short-circuiting unit 6 and the winding unit 5, the difference between the stators 1 of the brushless motors of different wiring states is only in the spot welding position, and the rest of the structures are the same, The stator 1 of the brushless motor of different wiring states can be manufactured using the same machine and steps, which is advantageous for automated production.

3. The first short circuit 61 and the second short circuit 62 of the short circuit unit 6 are in the form of a sheet and are disposed on the first bobbin 3 to facilitate automatic spot welding.

In summary, the stator 1 of the novel brushless motor has a structure that facilitates automated production, so that the purpose of the present invention can be achieved.

However, the above is only the embodiment of the present invention, and when it is not possible to limit the scope of the present invention, all the simple equivalent changes and modifications according to the scope of the patent application and the contents of the patent specification are still This new patent covers the scope.

1‧‧‧The stator of the brushless motor

2‧‧‧stator core

21‧‧‧ yoke

211‧‧‧ inner circumference

22‧‧‧ pole column

23‧‧‧ first end face

24‧‧‧second end face

3‧‧‧First Winding Rack

30‧‧‧Substrate

301‧‧‧ first surface

302‧‧‧ second surface

31‧‧‧ Surrounding class

310‧‧‧ first part

311‧‧‧First-order quilt

312‧‧‧First bump group

320‧‧‧Second part

321‧‧‧Second stage quilt

322‧‧‧Second bump set

330‧‧‧ third part

331‧‧‧ third-order quilt

332‧‧‧ third bump set

340‧‧‧ fourth part

341‧‧‧ fourth-order quilt

342‧‧‧fourth bump group

350‧‧‧ fifth part

351‧‧‧ fifth-order quilt

352‧‧‧ fifth bump group

360‧‧‧ sixth part

361‧‧‧ sixth-order quilt

362‧‧‧ sixth bump set

4‧‧‧Second reel

5‧‧‧Winding unit

500‧‧‧Wire

51‧‧‧ coil group

511‧‧‧ coil part

512‧‧‧Connecting Department

513‧‧‧Free end

6‧‧‧Short-circuit unit

61‧‧‧First short circuit

611‧‧‧Fixed section

612‧‧‧Clamping section

613‧‧‧First hot melt department

614‧‧‧Second hot melt department

62‧‧‧Secondary short circuit

621‧‧‧Fixed section

622‧‧‧ folder

623‧‧‧The third hot melt department

7‧‧‧Power cord

8‧‧‧Hol plate holder

9‧‧‧Hol plate

A‧‧‧ joint

B‧‧‧bump

c‧‧‧Connected

D‧‧‧bump

L‧‧‧ axis

D‧‧‧Axial

R‧‧‧ circumferential direction

S0‧‧‧Preparation steps

S1‧‧‧ Winding steps

S2‧‧‧ Short-circuit unit setting procedure

S3‧‧‧Thread cutting steps

S4‧‧‧ conduction steps

I‧‧‧start

II‧‧‧End

Other features and effects of the present invention will be apparent from the following description of the drawings, wherein: FIG. 1 is an embodiment of the stator of the novel brushless motor with three power cords and fixed with a Hall plate. FIG. 2 is an exploded perspective view of the first embodiment of the present embodiment; FIG. 3 is a perspective view of the first bobbin of the embodiment; Fig. 5 is a perspective view of the embodiment; Fig. 6 is a perspective view of another embodiment of the embodiment; Fig. 7 is a perspective view of another embodiment of the embodiment; A schematic diagram of a wiring state of the embodiment, illustrating that the stator is in a Y-string connection state; FIG. 9 is another schematic diagram of the wiring state of the embodiment, illustrating that the stator is in a Y-shaped and connected state; FIG. 10 is a view of the embodiment. FIG. 11 is a view showing another state of the wiring state of the embodiment, illustrating a state in which the stator is in a delta type and connected to a wire; FIG. 12 is a manufacturing method of the embodiment. a flow chart; Figure 13 is FIG. 14 is a plan view of the stator which has not been wound, prepared by the preparation step of the manufacturing method of the embodiment; FIG. 14 is a plan view of the stator which has not been wound, prepared by the preparation step of the manufacturing method of the embodiment; The top view of the stator and a wire being wound in a winding step of the manufacturing method, the state of the wire immediately after winding the two pole portions corresponding to the first portion and the fourth portion of the first bobbin Figure 16 is a plan view of the stator after the winding step of the method of the embodiment is completed; and Figure 17 is a perspective view of the stator after the winding step of the method of the embodiment is completed; Figure 18 is Another perspective view of the stator after the winding step of the method of the embodiment is completed.

Claims (5)

A stator of a brushless motor, which is suitable for connecting three power wires, the stator of the brushless motor comprises: a stator core, comprising a yoke portion which is hollow cylindrical and extends along an axis, and six symmetrically arranged around the axis And a pole portion protruding from the inner circumferential surface of the yoke portion toward the axis, and a first end surface and a second end surface opposite to the axis; a first bobbin disposed on the stator core a first end surface, the first bobbin includes a substrate that is annular about the axis and abuts the first end surface, and a surrounding layer disposed on the substrate, the substrate having a first one opposite the axis a surface and a second surface, the second surface abutting the first end surface, the axis is defined to extend along an axial direction, the wraparound member is protruded from the first surface of the substrate along the axis and about the axis a second winding frame disposed on the second end surface of the stator core; a winding unit including three poles respectively disposed around the opposite poles of the stator core a coil set, each coil set including two windings on respective pole portions a coil portion, a connecting portion electrically connected to the coil portions and outwardly wound around the outer side of the wraparound section, and two electrically connected to the coil portions and outwardly wound around a free end of the outer side of the wraparound class, a connecting portion and a free end of the coil group extend across the wraparound class to an outer side of the wraparound class, and the connecting portion and the free end are located at different positions in the axial direction with respect to the stator core; and a short-circuit unit is disposed And the first winding frame is configured to electrically connect the power cables, the shorting unit clamps the connecting portions of the coil groups and the free ends, and the portion clamped by the shorting unit is selectively melted And electrically connected to the coil sets. The stator of the brushless motor of claim 1, wherein the shorting unit comprises three first shorting pieces and a second shorting piece spaced apart from the first winding frame around the axis, the first short circuit The chip is configured to electrically connect the power lines, each of the first shorting pieces has a first hot melt portion that clamps the connection portion of one of the coil groups, and two of the free ends of the other coil group are respectively clamped a second heat-melting portion, wherein the first short-circuiting sheets are respectively pressed by different combinations of coil sets, and the second short-circuiting strips have three third hot-melt portions respectively sandwiching the connecting portions of the coil groups, At least six of the first hot melt portion, the second hot melt portion, and the third hot melt portion are thermally fused to be electrically connected to the coil groups. The stator of the brushless motor of claim 2, wherein a circumferential direction around the axis is defined, the surrounding classes of the first bobbin having sequentially arranged in the circumferential direction and respectively corresponding to the equipotential portions a first portion, a second portion, a third portion, a fourth portion, a fifth portion, and a sixth portion, the first portion having a first step group and a first bump group, The second portion has a second step group, and a second bump group, the third portion has a third step group, and a third bump group, the fourth portion has a fourth step And a fourth bump group, the fifth portion has a fifth step group, and a fifth bump group, the sixth portion has a sixth step group, and a sixth bump group, The first, second, third, fourth, fifth and sixth step groups are connected between the inner side and the outer side of the wrap-around class, and the connecting portions and the free ends corresponding to the winding unit are spanned The first, second, third, fourth, fifth, and sixth bump groups are respectively protruded from the first, second, and third portions along the axial direction. The fourth, fifth and sixth step groups are provided, and the connecting portions and the free ends corresponding to the winding unit are arranged around the outer side of the wraparound direction in the circumferential direction. The stator of the brushless motor of claim 3, wherein the first step group and the fourth step group of the first bobbin are in the axial direction compared to the second step group and the fifth step surface The group is adjacent to the stator core, and the third step group and the sixth step group of the first bobbin are away from the stator core in the axial direction compared to the second step group and the fifth step group. The stator of the brushless motor of claim 2, wherein each of the first shorting pieces has a fixing section fixed to the first bobbin, and a connecting the fixing section and clamping the same with the fixing section a clamping section of the winding unit, each clamping section has the first hot-melting section, and the second hot-melting section, the second short-circuiting piece has a fixing section fixed to the first winding frame, And an intervening section connecting the fastening section and clamping the winding unit together with the fixing section, the clamping section having the third hot melt section.