JPH0799756A - Electric motor stator manufacturing method - Google Patents

Abstract

(57) [Abstract] [Purpose] In a method for manufacturing a stator of an electric motor, a teeth iron core in which a plurality of teeth are integrally connected to each other by magnetic pole portions which are end portions on the inner peripheral side of the teeth by bridging portions. When separating and forming by bridging the bridge part, the coil is prevented from being damaged by the slag generated by the punching. In the punch 31 for punching out the bridging portion 18 of the tooth core 19, the cutting blade Sp of the punch 35 has a direction in which the cutting blade Sp moves away from the die 25 toward the inner peripheral side of the tooth core 19. The shear angle α is provided so as to tilt (upward). Therefore, when the bridging portion 18 is cut, the bridging portion 18 pops out to the inner peripheral side of the tooth iron core 19, and the coil 15 located on the outer peripheral side is not damaged.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for manufacturing a stator of an electric motor, in which an iron core is integrally formed with a plurality of teeth separate from the yoke iron core on the inner peripheral side of the yoke iron core.

[0002]

2. Description of the Related Art In a stator of an electric motor, for example, when a magnet wire is directly wound around a tooth to form a coil, the iron core 1 is generally integrated by press fitting as shown in FIG. It is composed of an annular yoke core 2 and a teeth core 3. The tooth core 3 is formed by integrally connecting the teeth 4 each having a wide magnetic pole portion 4b at the inner peripheral side end of the tooth main portion 4a with bridging portions 5 on both sides in the circumferential direction of the magnetic pole portion 4b. Teeth iron core 3
As a single unit, the slots 6 between the teeth 4 are open on the outer peripheral side.

The coil 7 (only three coils are shown in FIG. 14) is wound so that the magnet wire is inserted into the slot 6 from the outer peripheral side open portion before the teeth core 3 is integrated with the yoke core 2. It is wound by doing. After that, the teeth core 3 is integrated with the yoke core 2 by press-fitting the outer peripheral side end portions of the teeth 4 into the notch recesses 2 a in the inner peripheral portion of the yoke core 2.

However, in the stator manufactured as described above, since the magnetic pole portions 4b of the teeth 4 are connected to each other by the bridging portion 5, the magnetic flux leaks to the adjacent magnetic pole portion. Occurs, resulting in a problem of reduced efficiency. Therefore, for example, as seen in Japanese Examined Patent Publication No. 4-19787, it is considered to punch out the bridging portion 5 to separate the teeth 4.

[0005]

The punching of the bridge portion 5 is performed by a punching device equipped with a die and a punch. At the time of punching, the slag generated by the punching of the bridge portion 5 scatters in all directions. When the coil is damaged or slag remains on the inner peripheral surface of the magnetic pole part 4b and remains, and when assembled as an electric motor, the slag is caught between the magnetic pole part 4b and the rotor core to lock the rotor core. There is a risk that it will be in a state.

The present invention has been made in view of the above circumstances, and an object thereof is to remove a bridging portion of a tooth iron core by punching the bridging portion to separate the teeth into a plurality of teeth. The coil is damaged,
Another object of the present invention is to provide a method of manufacturing a stator of an electric motor in which there is no risk that slag will adhere and remain on the inner peripheral surface of the magnetic pole portion of the tooth.

[0007]

According to a first aspect of the present invention, there is provided a method of manufacturing a stator for an electric motor, wherein a plurality of teeth main portions that are formed by stacking stacking plates and radially project are formed on the inner circumference of the teeth main portions. A step of winding a coil between the tooth main portions of an annular tooth iron core integrally connected to each other by bridging portions on both sides in the circumferential direction of a magnetic pole portion which is a side end portion, and an outer peripheral side of the tooth main portion. A step of integrating the teeth core with the yoke core by press-fitting the ends into a plurality of fitting parts provided on the inner periphery of the annular yoke core; and cutting both sides in the circumferential direction of the bridging part. A die and a punch are provided, and among the cutting blades of the die and the punch, the cutting blade of the punch is inclined in a direction away from the die from the outer peripheral side to the inner peripheral side of the tooth iron core. Sheared The disconnect device, is characterized in performing a step of separating into a plurality of teeth by punching a bridge in order.

In the method of manufacturing a stator of an electric motor according to a second aspect of the present invention, a radial width dimension of a portion of the bridging portion that is punched out by the cutting blade portion of the die and the punch is set to be equal to or smaller than the thickness thickness of the stacking plate. It is characterized by that.

According to a third aspect of the present invention, there is provided a method of manufacturing a stator for an electric motor, wherein a protective cylindrical portion made of an insulating material is provided at both axial end portions of a tooth iron core in the vicinity of an outer peripheral side of a bridging portion, and It is characterized in that the coil end is arranged outside the protective cylindrical portion.

According to a fourth aspect of the present invention, there is provided a method of manufacturing a stator of an electric motor, wherein the shear angle of the cutting blade portion of the punch is set to 10 ° -40 °.

According to a fifth aspect of the present invention, there is provided a method of manufacturing a stator of an electric motor, wherein both sides of the punch in the width direction are provided with a relief gradient such that the width gradually narrows from the end on the cutting blade side toward the end on the opposite side. Is provided.

According to a sixth aspect of the present invention, there is provided a method of manufacturing a stator of an electric motor, wherein a puncher of the punching device is provided with a stripper for pulling out the punch from between the magnetic pole portions of the tooth after punching the bridging portion, and the stripper is connected to the bridge. It is characterized in that a shaping portion fitted to the inner peripheral surface of the magnetic pole portion of the tooth is provided prior to the punching of the entangled portion.

According to a seventh aspect of the present invention, there is provided a method of manufacturing a stator of an electric motor, wherein an air supply path for blowing out air to blow away a slag of a bridge portion punched on a punch side of a punching device is provided, and a die side is provided. It is characterized in that an intake path for sucking air is provided in order to suck the slag.

[0014]

According to the means of claim 1, since the cutting blade of the punch is provided with a shear angle, the bridging portion of each stacked plate is cut from the outer peripheral side to the inner peripheral side by the cutting blade of the punch. As it is done, it will be sequentially punched from the upper stacking board. For this reason, the slag generated by punching pops out toward the inside of the tooth core, and there is no risk that the coil existing on the outer peripheral side of the bridging portion will be damaged by the punching slag.

According to a second aspect of the present invention, among the bridging portions,
Since the radial width of the part to be cut by the die and punch is less than the plate thickness of the stacking plate, even if the cutting edge of the die has a shear angle, the teeth separated by punching the bridge There is no possibility that a burr that protrudes toward the inner peripheral side will be generated in the magnetic pole portion.

According to the third aspect of the present invention, since the coil end is located outside the protective cylindrical portion and the bridge portion is located inside the protective cylindrical portion, the punching slag of the bridge portion is temporarily located on the outer peripheral side. Even if it scatters, the slag does not reach the end of the coil because it is blocked by the protective cylinder.

According to the fourth aspect of the present invention, since the shear angle of the punch is set in the range of 10 ° to 40 °, it is possible to reliably scatter the punching slag of the bridge portion to the inner peripheral side of the teeth iron core. The punch is provided with a shear angle so that the punch is not weakened in strength and is not broken.

According to the means of claim 5, since the relief gradient is provided on both sides in the width direction of the punch, there is no possibility that a cutting edge of the punch is formed on the cutting blade portion.

According to the means of claim 6, since the stripper is provided with the shaping portion fitted to the inner peripheral surface of the magnetic pole portion of the tooth before punching the bridge portion by the punch, the tooth iron core is accurately positioned. In this state, the punch can punch out the bridge portion, and the shaping portion can prevent the magnetic pole portion from being deformed.

According to the seventh aspect of the invention, since the air is blown out from the air supply path and the air is sucked into the intake path, there is no risk that the punching residue remains attached to the inner peripheral surface of the magnetic pole portion of the tooth.

[0021]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT An embodiment of the present invention will be described below with reference to FIGS.
It will be described based on. 8 and 9 show the stator in a completed form, and its iron core 11 is an annular yoke iron core 1.
A plurality of teeth 13 are provided on the inner side of 2 to project. The teeth 13 are separate from the yoke iron core 12, and are formed in a substantially E-shape with the outer peripheral end of the tooth main portion 13a being a wide press-fitting portion 13b and the inner peripheral end being a wide magnetic pole portion 13c. ing. Then, the teeth 13 are integrated with the yoke iron core 12 by press-fitting the press-fitting portion 13b into a plurality of notch recesses 12a as fitting portions provided on the inner peripheral portion of the yoke iron core 12.

In each space between the teeth 13, that is, in each slot 14, there are coil sides of a plurality of coils 15 (only three are shown in FIG. 8) wound between two different tooth main portions 13a. 15a is stored. In this case, in order to insulate the coil 15 from the tooth 13, the tooth 13 has a pair of upper and lower slot insulators 1.
6 and 16 are attached. In order to insulate the coil side 15a of the coil 15 from the yoke core 12,
A wedge 17 is inserted on the outer peripheral side in the slot 15.

The pair of upper and lower slot insulators 16 are made of an insulating material, for example, plastic, and as shown in FIG. 11, slot insulators having a substantially U-shaped cross section fitted in the upper and lower half portions of each tooth 13. The portions 16a are integrally formed in a radial shape, and the protective cylindrical portion 16b is formed integrally on the inner peripheral side of the slot insulating portions 16a so as to project upward and downward. The protective cylindrical portion 16b is shown in FIG.
As shown in FIG. 5, the coil end 15b is located on the inner peripheral side of the coil end 15b so that the coil end 15b does not protrude to the inner peripheral side of the magnetic pole portion 13c of the tooth 13. In addition,
Since the pair of upper and lower slot insulators 16 and 16 are vertically symmetrical, only the upper one is shown in FIG.

Here, in the completed form of FIG. 8, the plurality of teeth 13 are independent of each other, but originally, as shown in FIG. 10, the magnetic pole portions 13c are connected to each other by a bridging portion 18 (specifically, It is configured as a tooth core 19 integrally connected via (see FIG. 12). The teeth iron core 19 is formed by stacking a large number of stacked plates S1 (see FIG. 2) formed by punching out, for example, silicon steel plates.
By punching out the bridging portion 18 as described below, the plurality of teeth 13 are separated from each other and are formed as independent ones. Then, as shown in FIG. 13, the magnetic pole portion 1 generated by punching out the bridge portion 18
The cut surfaces on both sides in the circumferential direction of 3c are formed in an arcuate convex shape C. The yoke core 12 is also formed by stacking a large number of stacked plates S2 (see FIG. 2) formed by punching out, for example, silicon steel plates.

Since the teeth iron core 19 has a structure in which a plurality of teeth 13 are connected to each other at the magnetic pole portions 13c through the bridging portions 18, the teeth main portions 13a of the teeth 13 are radially arranged. It has a protruding annular shape. Therefore, in the case of the teeth core 19 alone,
The slot 14 is open on the outer peripheral side. Then, as shown in FIG. 12, a trapezoidal notch 18a is formed on the outer peripheral surface side of the bridge portion 18, and the notch 18a is formed.
The radial width dimension L of the bridging portion 18 becomes
It is narrower than that of c. here,
The radial width L of the bridging portion 18 is set to be equal to or less than the thickness of the stacking plate S1. Specifically, in this embodiment, the thickness of the stacking plate S1 is 0.5 mm, The radial width dimension L is set to 0.4 mm.

A punching device 20 for punching the bridging portion 18 of the tooth core 19 is shown in FIG. In addition, the punching of the bridging portion 18 by this punching device 20,
Teeth iron core 19 wound with a coil 15 as described later.
Is integrated with the yoke iron core 12.

In FIG. 1, a plurality of guide posts 22 (only one is shown) are erected on a die holder 21 attached to a bed (not shown) of the press, and a ram of a press (not shown) is provided on the guide posts 22. A punch holder 23 attached to the is supported by a retainer 24 so as to be vertically movable.

A die 25 is attached to the die holder 21. A circular positioning recess 26 into which the yoke core 12 is fitted is formed in the die 25, and a hole 27 is formed in the center of the bottom of the positioning recess 26 to vertically penetrate the die 25. An annular escape groove 28 for accommodating the coil end 15b protruding to the side, the protective cylindrical portion 16b, and the wedge 17 is formed.

In the annular projecting wall portion left on the inner peripheral side of the escape groove 28, a substantially convex shaped split groove 29, as shown in FIG. 7, is the same as the pitch interval of the bridging portions 18 of the teeth core 19. They are formed with a pitch interval, and by the formation of the dividing grooves 29, the annular protruding wall portion is divided into a plurality of fence-shaped protruding portions 30 having a substantially T-shaped cross section. The split groove 2
9 extends to the lower end of the inner peripheral surface of the hole 27. The upper end surface of the fence-shaped protrusion 30 is flush with the bottom surface of the positioning recess 26, and the yoke core 12 is inserted into the positioning recess 26.
When the teeth are inserted, the teeth iron core 19 integrated with the teeth is placed on the upper end surface of the fence-shaped protrusion 30. At this time, the teeth iron core 19 is circumferentially positioned such that the magnetic pole portion 13c is located on the wide portion 30a of the fence-shaped protrusion 30 and the bridging portion 18 is located on the narrow portion 29a of the split groove 29. It has become so.

On the other hand, a punch 31 is attached to the punch holder 23, and a stripper 32 having an ejector pin 32a is attached so as to be vertically movable. The stripper 32 is urged downward by the compression coil spring 33, and is constantly pushed down to a position where the lower end of the ejector pin 32a projects downward from the lower end of the punch 31.

A hole 32b through which the punch 31 is inserted is formed in the stripper 32, and a large number of protrusions 34a are provided on the inner peripheral portion of the hole 32b. The lower portions of these protrusions 34a are projected downward from the stripper 32 to form a shaping unit 34. When the stripper 32 descends as the ram of a press (not shown) descends, the protrusions 34a form the die 25. The inner end surface of the outer peripheral side is fitted into both sides of the inner peripheral surface of the magnetic pole portion 13c by penetrating inside the tooth iron core 19 mounted on the fence-shaped protrusion 34b.

The stripper 32 is the ejector pin 3
2a descends until it comes into contact with the teeth core 19, but at this time, the lower end portion of the protrusion 34a projects downward from the lower end surface of the teeth core 19, and as shown in FIG.
Two a's are set as a set and penetrate into both sides in the circumferential direction within the wide portion 29b of each split groove 29.

The outer periphery of the punch 31 is shown in FIG.
As also shown in FIG. 2, the two ridges 3 in which the punch portion 35 having a substantially convex cross section intrudes into the wide portion 29b of each split groove 29.
It is projected intermittently so as to be located between 4a.
The narrow portion 35a on the front end side of the punch portion 35 is projected outward from the outer peripheral end surface of the protruding portion 34a of the shaping portion 34, as shown in FIG. When the punch 31 descends, it comes into contact with the bridging portion 18 of the tooth core 19.

The narrow portion 35a of the punch portion 35 is connected to the bridging portion 18
When it comes into contact with the bridge portion 18, the bridging portion 18 is cut by the cutting action of the narrow portion 35a. Then, the punch portion 35 descends while cutting the bridging portion 18, and finally descends to a position where the lower end portion enters the split groove 29 of the die 25.
At this time, the narrow portion 35a of the punch portion 35 is adapted to fit into the narrow portion 29a on the tip side of the split groove 29 as shown in FIG.

Here, the bridging portion 18 is cut by the split groove 29 functioning as a die hole and the punch portion 35, but on the split groove 29 side, the wide portion 30 of the fence-shaped projection 30 is formed.
Edges on both sides in the circumferential direction of a are cutting blades Sd for punching
And the narrow portion 35 on the punch portion 35 side.
Both sides of b in the circumferential direction are formed as cutting blades Sp for punching. Then, the cutting blade portions Sd, Sp
Is formed in an arc shape so that both sides in the circumferential direction of the magnetic pole portion 13c are formed in the arc convex surface C by cutting the bridging portion 18, specifically, the portion Sd is formed in the arc convex surface and Sp is formed in the arc concave surface.

As shown in FIG. 2, the cutting blade portion Sp of the punch portion 35 is inclined so that the cutting blade portion Sp gradually separates from the die 25 from the outer peripheral side to the inner peripheral side of the tooth iron core 19. That is, the shear angle α is attached so as to incline obliquely upward from the outer peripheral side of the tooth iron core 19 toward the inner peripheral side. Further, on both sides in the width direction of the punch portion 35, there is provided a relief gradient indicated by an angle δ in FIG. 6, and the punch portion 35 has a lower cutting blade portion Sp due to the relief gradient δ.
It gradually narrows from the top. The relief gradient δ is set to 1/100, for example.

In the punching device 20 thus constructed, the punch holder 23 has an air passage 37 connected to a compressed air supply source (not shown) such as a compressor through a hose 36, and The punch 31 is formed with a plurality of branch passages 38 whose upper ends communicate with the air passages 37, and the hose 36, the air passages 37 and the branch passages 38 form an air supply passage 39. And
An air guide 40 that guides the compressed air blown from the branch passage 37 toward the cutting blade Sp of the punch 35 is attached to the lower surface of the punch 31.

On the other hand, a hole 41 is formed in the die holder 21 so as to communicate with the hole 27 of the die 25, and
A closing plate 42 is attached so as to close the lower surface of the hole 41. Then, in the closing plate 42, the intake hole 4
3, the intake hole 43 is connected to an intake device (not shown) such as a vacuum suction device via a hose 44. The hole 41, the intake hole 43, and the hose 44 constitute an intake passage 45. ing.

Next, a method for manufacturing the stator shown in FIGS. 8 and 9 will be described. First, the slot insulator 16 is attached to the teeth core 19 from above and below the teeth core 19 alone. Then, the operation of winding the magnet wire between the two tooth main portions 13a such that the magnet wire is inserted into the required two slots 14 from the open portion on the outer peripheral side thereof is repeated a plurality of times to form a plurality of coils. 1
Wind up 5.

After the plurality of coils 15 are wound between the tooth main portions 13a of the tooth core 19 in this manner, the press-fitting portions 13b of the teeth 13 are press-fitted into the notch recesses 12a of the yoke core 12 to form the tooth core 19. Integrated with the yoke core 12. Then, the yoke core 12 in the slot 14
Insert wedge 17 on the side.

Thereafter, the integrated yoke core 12 and teeth core 19 are set in the die 25 of the punching device 20. At this time, the yoke core 12 has the positioning recess 26
As shown in FIG. 4, the magnetic pole portion 13c of the tooth iron core 19 is placed on the wide portion 30a of the fence-shaped protrusion 30 of the die 25, and the bridging portion 18 is inserted into the split groove 29. The positioning is performed so as to exist on the narrow portion 29a of the.

When the ram of the press (not shown) descends in such a positioning state, first, the shaping section 3 of the stripper 32 is moved.
The ridge portion 34a of No. 4 enters the inside of the teeth iron core 19,
The outer peripheral end surface of the protruding portion 34a is fitted to the inner peripheral surface of the magnetic pole portion 13c. By fitting the protruding portion 34a to the magnetic pole portion 13c, even if the tooth core 19 is slightly deviated from the regular position, the tooth iron core 19 is corrected to the regular position. Then, the lower end of the protruding portion 34a is the wide portion 29 of the split groove 29 of the die 25.
When it enters the inside of b, the ejector pin 32a of the stripper 32 comes into contact with the yoke core 12 and
The teeth core 19 is pressed and fixed to the bottom surface of the positioning recess 26 and the fence-shaped projection 30.

After that, since the stripper 32 is stopped, the punch holder 23 comes down while compressing and compressing the compression coil spring 33, whereby the punch portion 35 of the punch 31 is projected on the protruding portion 34a of the shaping portion 34. Then, the narrow portion 34a comes into contact with the bridging portion 18 of the tooth core 19 as shown in FIG. Then,
As the punch 31 descends thereafter, the bridging portion 18 is cut by the cutting blade portion Sp of the punch portion 35 as shown in FIG.

At this time, since the cutting blade portion Sp is provided with the shear angle α, the bridging portion 18 of each stacking plate S1 serves as a pedestal for cutting the stacking plate S1 located therebelow. It will be in the state of being sequentially cut by, and each stacking plate S
The bridging portion 18 of 1 is a cutting blade portion Sp provided with a shear angle α.
As a result, cutting is performed from the outer peripheral side toward the inner peripheral side. Therefore, the bridging portion 18 is sequentially cut from the upper stack S1 and the teeth core 19 is cut by the cutting.
The slag of the bridging portion 18 separated from (to be simply referred to as a slag hereinafter) pops out toward the inner peripheral side of the teeth iron core 19.
Further, even if there is a slag that has sprung toward the outer peripheral side of the tooth iron core 19, the slag will hit the inner peripheral surface of the protective cylindrical portion 16b and will not protrude further to the outer peripheral side.

Then, the slag is blown downward by the air blown from the branch passage 38 guided by the air guide 40, and is multiplied by the air sucked into the air intake hole 43 to enter the hose 44, and a predetermined discarding section. Be eliminated in place. When the bridging portions 18 of all the stacked plates S1 are cut (punched) as described above, the plurality of teeth 13 are separated from each other as shown in FIG.

Here, the cutting surfaces C on both sides in the circumferential direction of the magnetic pole portion 13c generated by the punching of the bridging portion 18 are naturally the cutting grooves Sd of the split groove 29 and the punch portion 35.
And the same shape as Sp, and the corners on the inner peripheral surface side on both sides in the circumferential direction of the magnetic pole portion 13c are formed in the same shape as the cutting blade portions Sd and Sp, that is, formed into an arcuate convex shape C as shown in FIG. Is.

After the bridging portion 18 has been punched out as described above, the ram of the press (not shown) starts to rise, but at this time, the compression coil spring 33 is in a compressed state, so the stripper 32 uses the compression coil spring. The yoke core 12 is pressed until 33 is fully extended. Therefore, the yoke iron core 12 and the teeth 1 integrated with the yoke iron core 12 are formed.
3 is still pressed against the die 25, so that the punch 31 comes out from the inside of the tooth 13 while the iron core 11 is left on the die 25. After that, the compression coil spring 33 is fully extended, so that the stripper 32 also rises and returns to the original state. Then, the yoke core 12 is taken out from the positioning recess 26 of the die 25.
As described above, the stator shown in FIGS. 8 and 9 is completed.

As described above, according to this embodiment, since the coil 15 is wound between the tooth main portions 13a before the teeth iron core 19 is integrated with the yoke iron core 12, the magnet wire is placed in the slot 14 on the outer peripheral side thereof. It is possible to insert the coil 15 from the open portion, and the winding operation of the coil 15 can be easily performed.

Further, the plurality of teeth 13 are connected to the bridging portion 18
Are integrally connected by the tooth core 1, that is, the teeth iron core 1
Since the press-fitting portions 13b are press-fitted into the cutout recesses 12a in the integrated state as 9, the teeth 13 separated from each other by punching out the bridging portions 18 are pressed in one by one. The press-fitting work becomes easy. After the teeth core 19 is integrated with the yoke core 12, the bridging portion 18 is punched out. Therefore, even if the teeth 13 are separated from each other by the punching of the bridging portion 18, there is no risk of falling off.

At the time of punching the bridging portion 18 by the punch portion 35, prior to the punching (cutting), the ridge portion 34a of the shaping portion 34 of the stripper 32 is changed to the magnetic pole portion 13.
Since the tooth core 19 is fitted to the inner peripheral surface of c, the bridging portion 18 is punched out in a state where the tooth iron core 19 is positioned at a proper position in relation to the cutting blade portions Sd and Sp of the die 25 and the punch 31. Therefore, there is no possibility that the shape of the magnetic pole portion 13c of the tooth 13 after the punching of the bridging portion 18 may be deformed.

Moreover, since the bridging portion 18 is punched out with the protruding portion 34a supporting the magnetic pole portion 13c from the inside, the press-fitting portion 13 of the tooth 13 is formed by the impact force at the time of punching.
There is no deviation of b from the recess 12a and deformation of the magnetic pole portion 13c. Therefore, there is no fear that the circularity of the circumferential surface formed by the magnetic pole portions 13c of the plurality of teeth 13 will change, and when a rotor (not shown) is incorporated, the rotor core and the inner circumferential surface of the magnetic pole portion 13c are not separated. The gap that occurs between the and is even over the entire circumference.

Further, the cutting blade portion Sp of the punch portion 35 is
Since the shear angle α is provided so as to be inclined obliquely upward toward the inner peripheral side, the bridging portion 18 is the upper stacking plate S.
Since the ones are sequentially punched out (cut), the bridging portions 18 can be surely punched with a small force as compared with the case where the bridging portions 18 of each stack S1 are punched at once.
Moreover, since the bridging portion 18 of each stack S1 is cut from the outer peripheral side toward the inner peripheral side by the cutting blade Sp,
The shavings generated by the cutting will come out to the inner peripheral side of the teeth iron core 19, and there is no fear that the shavings will hit the coil 15 and damage it.

Here, in particular, the cutting blade portion Sp of the punch portion 35
Since the shear angle α is set in the range of 10 ° to 40 °, the punch portion 35 becomes too sharp and is broken, or the slag cannot be thrown to the inner peripheral side of the teeth iron core 19. No trouble will occur. What is more, when the shear angle α exceeds 40 °, the punch portion 35 becomes an acute angle and the thickness of the punch portion 35 becomes thin.
There is a risk of breakage. When the shear angle α is less than 10 °, the teeth core 19 is cut when the bridging portion 18 is cut.
The component force toward the inner peripheral side of the tooth core becomes insufficient, and there arises a problem that the slag does not project to the inner peripheral side of the tooth iron core 19, but such a problem does not occur in the present embodiment.

In addition, the protective cylinder portion 16b is projected on the inner peripheral side of the upper and lower end surfaces of the tooth iron core 19 and the coil end 15b is formed.
Are located outside the protective cylinder portion 16b, so that even if the slag scatters on the outer peripheral side of the teeth iron core 19, the slag must collide with the protective cylinder portion 16b and scatter further outside. It is possible to prevent the coil 15 from being scratched more reliably.

Further, the punching device 20 is provided with an air supply passage 39 and an intake passage 45, and the slag is multiplied by an air flow blown out from the branch passage 38 and sucked into the intake hole 43, so that a predetermined discarding portion is formed. Since it is discharged to the place, there is no risk that the slag adheres to and remains on the magnetic pole portion 13c of the tooth 13, and when assembled as a motor, the rotor core engages the slag with the magnetic pole portion 13c and locks it. It is possible to prevent the occurrence of accidents such as

On the other hand, the notch 18 is formed on the outer peripheral surface side of the bridge portion 18.
a is formed, and the radial width of the bridging portion 18 is the stacking plate S.
Since the thickness is narrower than 1 plate, the shearing angle α is provided at the cutting blade part Sp of the punch part 35, so that the bridging part 18 of each stacking plate S1 moves from the outer peripheral side to the inner peripheral side. Even if there is a situation in which it is cut, burrs are less likely to occur at the end of the arcuate convex surface C, which is the final cut, on the inner peripheral surface side.

Moreover, since the cutting blade portions Sd and Sp of the die 25 and punch 31 of the punching device 20 are formed in a circular arc convex surface shape and a circular arc concave surface shape, the cutting blade portion S is formed.
Both sides in the circumferential direction of the magnetic pole portion 13c generated by punching the bridging portion 18 with d and Sp are formed into arcuate convex surface shapes C. Therefore, the corners on the inner peripheral surface side of the magnetic pole portion 13c are formed into a substantially right angle. Compared with the case of punching, it is possible to prevent the occurrence of burrs at the end portion on the inner peripheral surface side of the arcuate convex surface shape C.

Moreover, since the punch portion 35 is provided with a clearance gradient δ, a so-called galling phenomenon occurs at the time of cutting the bridging portion 18 and hardened cutting powder adheres to the cutting blade Sp to form a component cutting edge. It is possible to prevent the trouble that occurs. Therefore, the so-called sharpness of the cutting blade portion Sp can be favorably maintained, and the bridging portion 18 can always be favorably cut, and the end portion of the magnetic pole portion 13c on the inner peripheral surface side of the circular arc convex surface shape C can be flashed. It is possible to more reliably prevent the occurrence of.

In this way, it is possible to effectively prevent the occurrence of burrs at the end portion of the magnetic pole portion 13c on the inner peripheral surface side of the arcuate convex surface C, that the gap between the rotor core and the magnetic pole portion 13c is extremely small. This means that it can be set small, and the efficiency of the motor can be improved.

In the above embodiment, the magnet wire is directly wound between the tooth main portions 13a so that the magnet wire is inserted into the slot 14 from the outer peripheral side opening portion thereof, so that the coil 15 is provided between the tooth main portions 13a. Although it was wound, the coil formed in a separate process was used for slot 1
4 may be inserted from the outer peripheral side open portion and wound.

[0061]

As described above, according to the present invention, the following effects can be obtained. In the method for manufacturing a stator of an electric motor according to claim 1, the shearing blade portion of the punch is tilted in a direction away from the cutting blade portion of the die from the outer peripheral side of the tooth core toward the inner peripheral side. By providing the corners, the bridging part can be sequentially cut from only the upper stacking plate, so the bridging part can be cut (punched) with a small force, and the bridging part can be removed. Since it will come out to the inner peripheral side of the tooth iron core, there is no risk of the coil being damaged by the slag.

In the method of manufacturing a stator of an electric motor according to a second aspect of the present invention, the radial width dimension of the portion of the bridging portion that is punched out by the cutting blade portion of the die and the punch is set to be equal to or less than the plate thickness dimension of the stacking plate. Therefore, even if there is a situation in which the bridging portion is cut from the outer peripheral side toward the inner peripheral side due to the shear angle provided on the cutting blade portion of the punch, the bridge portion is separated by cutting. The burrs protruding toward the inner peripheral side are less likely to occur at the cut portion of the magnetic pole portion of the formed tooth.

In the method of manufacturing a stator of an electric motor according to claim 3, protective cylindrical portions made of an insulating material are provided at both axial end portions of the teeth iron core so as to project near the outer peripheral side of the bridging portion, and Since the coil end is located outside the protective cylinder, even if the scraps at the bridge part fly to the inner circumference of the tooth core, the scraps are blocked by the protection cylinder. It is possible to more surely prevent the coil from being damaged.

In the method of manufacturing the stator of the electric motor according to the fourth aspect, since the shear angle of the punch is set to 10 ° to 40 °, the punch becomes weak in strength, and the bridge slag is removed. There is no problem such as that it does not stick out to the inner circumference side of the teeth iron core.

In the method for manufacturing a stator of an electric motor according to a fifth aspect, the clearance angle is gradually narrowed on both sides in the width direction of the punch from the end on the cutting blade side toward the end on the opposite side. By providing the above, it is possible to prevent the cutting blade portion of the punch from forming a constituent blade edge, and it is possible to always satisfactorily cut the bridging portion.

In the method of manufacturing a stator of an electric motor according to claim 6, a puncher of the punching device is provided with a stripper for pulling out a tooth iron core from the punch after punching a bridge portion,
By providing the stripper with a shaping portion that fits on the inner peripheral surface of the magnetic pole portion of the tooth prior to punching out the bridging portion, the bridging portion can be cut after the teeth iron core is positioned at a regular position, The shaping portion can prevent the magnetic pole portion from being deformed.

In the method of manufacturing a stator of an electric motor according to a seventh aspect, an air supply passage for blowing away the slag of the punched bridge portion is provided on the punch side of the punching device, and the slag is sucked on the die side. By providing the intake passage, there is no risk that the punched slag remains attached to the inner peripheral surface of the magnetic pole portion of the tooth.

[Brief description of drawings]

FIG. 1 is a vertical sectional view of a punching device showing an embodiment of the present invention.

FIG. 2 is a partial vertical cross-sectional view of a punching device shown in a state immediately before punching a bridge portion.

FIG. 3 is a view corresponding to FIG. 2 showing a state where the bridge portion is being punched out.

4 is a cross-sectional view taken along the line III-III in FIG.

FIG. 5 is a cross-sectional view showing a state in which the punch is lowered to the lowest position.

FIG. 6 is a partial perspective view of a punch.

FIG. 7 is a partial perspective view of a die.

FIG. 8 is a transverse sectional view of the stator core.

FIG. 9 is a vertical sectional view of a stator core.

FIG. 10 is a plan view of the teeth iron core.

FIG. 11 is a partial perspective view of a slot insulator.

FIG. 12 is a partially enlarged plan view of the teeth iron core.

FIG. 13 is a view corresponding to FIG. 12 after punching out the bridge portion.

FIG. 14 is a view corresponding to FIG. 8 showing a conventional example.

[Explanation of symbols]

11 is an iron core, 12 is a yoke iron core, 12a is a notched recess (fitting portion), 13 is a tooth, 13a is a tooth main portion, 13
c is a magnetic pole part, 15 is a coil, 18 is a bridging part, 19 is a teeth iron core, 20 is a punching device, 25 is a die, 29 is a split groove, 30 is a fence-like projection, 31 is a punch, 32 is a stripper, 34 is a shaping part, 35 is a punch part, 39 is an air supply path, 4
Reference numeral 5 is an intake passage, and Sd and Sp are cutting blades.

Claims (7)

[Claims] 1. A plurality of teeth main portions that are formed by stacking stacked plates and project in a radial direction are mutually connected by bridging portions on both sides in the circumferential direction of a magnetic pole portion that is an inner peripheral side end portion of the teeth main portions. A step of winding a coil between the tooth main portions of an annular tooth iron core integrally connected, and a plurality of outer peripheral end portions of the tooth main portion provided on the inner peripheral portion of the annular yoke iron core; A step of integrating the teeth core with the yoke core by press-fitting into the fitting portion, and a die and a punch for cutting both sides in the circumferential direction of the bridging portion, and among the cutting blade portions of the die and the punch. By a punching device provided with a shear angle so that the cutting blade portion of the punch is inclined in a direction away from the cutting blade portion of the die from the outer peripheral side of the teeth iron core toward the inner peripheral side, a bridging portion is formed. Punch out multiple tees Method for manufacturing a stator of an electric motor and a step formed by sequentially executed for separating the scan. 2. The radial width dimension of a portion of the bridging portion that is punched out by the cutting blade portion of the die and the punch is set to be equal to or smaller than the plate thickness dimension of the stacking plate. Manufacturing method of stator of electric motor. 3. A protective cylindrical portion made of an insulating material is provided at both axial end portions of the tooth core in the vicinity of the outer peripheral side of the bridging portion, and a coil end of the coil is provided outside the protective cylindrical portion. The method of manufacturing a stator of an electric motor according to claim 1, wherein the stator is positioned. 4. The shear angle of the cutting blade of the punch is 10 ° to
The method of manufacturing a stator of an electric motor according to claim 1, wherein the stator is set at 40 °. 5. A relief slope is provided on both sides in the width direction of the punch so that the width gradually narrows from the end on the cutting blade side toward the end on the opposite side. Item 5. A method for manufacturing a stator of an electric motor according to any one of items 1 to 4. 6. The punch side of the punching device is provided with a stripper for pulling out the punch from between the magnetic pole portions of the tooth after punching the bridging portion, and the stripper has a magnetic pole of the tooth prior to punching the bridging portion. The method of manufacturing a stator of an electric motor according to claim 1, further comprising a shaping portion fitted to an inner peripheral surface of the portion. 7. The punch side of the punching device is provided with an air supply path for blowing air to blow away the slag at the bridge portion that has been punched out, and the die side is provided with air to suck the slag. 7. The method for manufacturing a stator of an electric motor according to claim 1, wherein an intake passage for drawing in is provided.