JP2001078404A - Method of forming winding - Google Patents

Abstract

PROBLEM TO BE SOLVED: To acquired necessary distance between the end portions of a conductor segment. SOLUTION: A large segment 231, that is bent into a U-shape is allocated at the external side of a small segment which is also bent into a V-shape. Thereby, the end portion of a small segment 232 is placed surely in contact with the end portion of the large segment 231. Thereafter, the small segment 232 and large segment 231 are twisted, while these are combined and these small segment 232 and large segment 231 are inserted into the prescribed slot provided to the stator iron core, while the remain in the combined state.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for forming windings of a rotating electric machine such as an AC generator for a vehicle.

[0002]

2. Description of the Related Art As a stator used in an automotive alternator, a stator having a winding formed by joining a plurality of conductor segments is conventionally known. For example, WO98 / 54823 discloses a stator in which a plurality of U-shaped conductor segments are inserted from one end face side of a stator core, and then the opposite ends are joined together to form a stator. Is disclosed. This stator has a feature that a regularly arranged winding can be easily formed as compared with a case where a winding is formed by winding a continuous conductor winding.

[0003] In the above-mentioned WO 98/54823, the conductor inserted into each slot of the stator core is joined at the ends of the conductors housed in different slots, and each joint is formed in the shape of the stator core. Are arranged along the circumferential direction at equal intervals. For example, the above-mentioned publication discloses a stator in which four conductors are inserted into each slot as shown in FIG. The winding of such a stator is formed by laminating a first conductor segment formed in a substantially U shape and a U-shaped second conductor segment having a larger bending radius than the first conductor segment, and then twisting. Is inserted into a slot of the stator core, and the ends of the anti-turn portions of the conductor segments are joined together.

[0004]

By the way, in the conventional winding forming method in which the first and second conductor segments are overlapped and formed by twisting and then inserted into the slots of the stator core, the two superposed two segments are twisted. If the distance between the tips of the first conductor segments included in the conductor segments varies, the tips of the first conductor segments may come into contact with each other. Such contact between the tips also occurs after the first conductor segment is inserted into each slot of the stator core. For example, in FIG. 5, the second tip 232d and the third tip 232e when viewed from the radial inside correspond to the first conductor segment, and when these tips 232d and 232e contact, This is not preferable because a short circuit is likely to occur between them. Particularly, even if the distal ends 232d and 232e are separated from each other, they cannot be deformed as desired by springback.
Correction of this part is not easy. For this reason, in order to reliably separate the contacting end portions 232d and 232e, a method of inserting an insulating material between them may be considered, but this is not preferable because the number of parts increases.

The present invention has been made in view of the above points, and an object of the present invention is to provide a winding forming method capable of securing a distance between the end portions of conductor segments.

[0006]

In order to solve the above-mentioned problems, according to the winding forming method of the present invention, a substantially U-shaped first conductor segment is formed outside a substantially V-shaped first conductor segment. A first step of arranging the second conductor segment, and a step of setting the distance between the distal ends of the first conductor segment to a predetermined value in a state where the first conductor segment and the second conductor segment are combined. Step 2, a third step of simultaneously twist-forming the first conductor segment and the second conductor segment in a combined state, and the first conductor segment and the second conductor segment are simultaneously formed on the laminated core. And a fourth step of inserting into the slot. As described above, by disposing the second conductor segment molded into a substantially U shape outside the first conductor segment molded into a substantially V shape, the tip of the first conductor segment arranged inside is formed. In the portion, the elastic force for maintaining the V-shape and the force pushed by the second conductor segment arranged on the outside act, so that the tip of the first conductor segment and the second conductor segment The tip will come into contact with it. Therefore, the distance between the tip portions of the first conductor segments can be ensured.

In addition, the first conductor segment is formed so that the interval increases from the turn portion to the tip portion, and the second conductor segment is formed substantially parallel from the turn portion to the tip portion. In a state before the first and second conductor segments are combined, it is desirable that the tip interval of the first conductor segment is set wider than the tip interval of the second conductor segment. By arranging the second conductor segment having a narrow tip interval from the outside of the first conductor segment having a wide tip interval as described above, the distance between the tip portions of the included first conductor segments can be reduced. Therefore, it is possible to prevent contact between these tip portions before and after assembling.

Further, the first step is performed by the above-described fourth step.
The first and second portions protruding from different slots after arranging a portion from the turn portion to the tip portion of the second conductor segment on the inner diameter side and the outer diameter side of the laminated iron core formed in an annular shape. Fifth, which joins the inner peripheral ends of the two conductor segments and the outer peripheral ends of the first and second conductor segments projecting from different slots.
It is desirable to include the step of: In the case where the inner peripheral ends of the first and second conductor segments are joined together and the outer peripheral ends are joined together, the inner peripheral end of the first conductor segment protruding from a certain slot It is necessary to ensure an insulation state between the first conductor segment and the outer end of the other first conductor segment protruding from the other slot. Since the distance between the end and the outer peripheral end can be ensured, partial short-circuiting of the winding in which four or more conductors are accommodated in the same slot can be performed without using another insulating member or the like. It can be effectively prevented.

In addition, a plurality of combinations of the conductor segments in which the first conductor segments are arranged inside the second conductor segments are simultaneously formed, and the combination of the plurality of conductor segments is simultaneously twist-formed. After that, it is desirable to simultaneously insert a combination of a plurality of conductor segments into the slots of the laminated core. Accordingly, it is possible to prevent a short circuit in the winding, and at the same time, to reduce the number of man-hours for manufacturing the winding, thereby achieving cost reduction.

[0010]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS A vehicle AC generator according to an embodiment of the present invention will be described below in detail with reference to the drawings.

FIG. 1 is a diagram showing the overall configuration of an automotive alternator. The vehicle alternator 1 shown in FIG. 1 includes a stator 2, a rotor 3, a frame 4, a rectifier 5, and the like.

The stator 2 includes a stator core 22, a conductor segment 23 forming a stator winding 21, and a stator core 2.
2 and an insulator 24 for electrically insulating between each conductor segment 23. The detailed structure of the stator 2 will be described later.

The rotor 3 sandwiches a field winding 8 in which an insulated copper wire is cylindrically and concentrically wound around a shaft 6 through pole shafts 7 each having six claws. It has a rigid structure. An axial-flow-type cooling fan 11 is attached to the end face of the pole core 7 on the front side by welding or the like to discharge the cooling air sucked from the front side in the axial direction and the radial direction. Similarly, a centrifugal cooling fan 12 is attached to the end face of the rear pole core 7 by welding or the like to discharge the cooling air sucked from the rear side in the radial direction.

The frame 4 accommodates the stator 2 and the rotor 3. The rotor 3 is supported rotatably about a shaft 6, and is mounted on the outer peripheral side of the pole core 7 of the rotor 3. Stator 2 arranged via a predetermined gap
Has been fixed. In addition, the frame 4 includes the stator core 2
2 has a discharge window 42 for cooling air at a portion facing the stator winding 21 protruding from the axial end face, and a suction window 41 at the axial end face.

Vehicle alternator 1 having the above structure
When a rotational force from an engine (not shown) is transmitted to the pulley 20 via a belt or the like, the rotor 3 rotates in a predetermined direction. In this state, by applying an excitation voltage to the field winding 8 of the rotor 3 from the outside, each claw of the pole core 7 is excited, and a three-phase AC voltage can be generated in the stator winding. A predetermined direct current is extracted from the output terminal of the rectifier 5.

Next, details of the stator 2 will be described.
FIG. 2 is a partial cross-sectional view of the stator 2. FIG.
FIG. 3 is a perspective view of a conductor segment constituting a stator winding.

The stator winding 21 provided in the slot 25 of the stator core 22 is constituted by a plurality of electric conductors, and each slot 25 accommodates an even number (four in the present embodiment) of electric conductors. I have. Also, 4 in one slot 25
As shown in FIG. 2, the electric conductors are arranged in a line in the order of the inner end layer, the inner middle layer, the outer middle layer, and the outer end layer from the inside in the radial direction of the stator core 22.

The electric conductor 2 in the inner end layer in one slot 25
31a is paired with the electric conductor 231b of the outer end layer in the other slot 25 separated by one magnetic pole pitch in the clockwise direction of the stator core 22. Similarly, one slot 25
The inner and middle electric conductors 232a are separated from the other slots 2 by one magnetic pole pitch in the clockwise direction of the stator core 22.
5 and a pair with the outer middle electric conductor 232b. These pairs of electric conductors are connected via the turn portions 231c and 232c by using a continuous wire on one end face side in the axial direction of the stator core 22.

Accordingly, on one end face side of the stator core 22, a continuous line connecting the outer middle electric conductor 232b and the inner middle electric conductor 232a is formed with the outer end electric conductor 231b and the inner middle layer. A continuous line connecting the electric conductor 231a will surround it. Thus, on one end face side of the stator core 22, the turn portion 232c as a connection portion of a pair of electric conductors serves as a connection portion of another pair of electric conductors housed in the same slot 25. Is surrounded by the turn part 231c. A middle coil end is formed by connecting the outer middle electric conductor 232b and the inner middle electric conductor 232a, and an end coil end is formed by connecting the outer end electric conductor 231b and the inner end electric conductor 231a. You.

On the other hand, the electric conductor 232a of the inner middle layer in one slot 25 is also connected to the electric conductor 231a 'of the inner end layer in the other slot 25 separated by one magnetic pole pitch in the clockwise direction of the stator core 22. In pairs. Similarly, the outer-layer electric conductor 231b ′ in one slot 25 is also paired with the outer-layer electric conductor 232b in the other slot 25 that is one pole pitch away from the stator core 22 in the clockwise direction. No. These electric conductors are connected on the other end face side of the stator core 22 in the axial direction.

Therefore, on the other end face side of the stator core 22, the outer joint connecting the outer end electric conductor 231b 'and the outer middle electric conductor 232b is connected to the inner end electric conductor 231a'. The inner joints connecting the inner and middle electric conductors 232a are arranged so as to be shifted from each other in the radial direction and the circumferential direction. Outer end electric conductor 231
The connection between b 'and the outer middle electric conductor 232a and the connection between the inner end electric conductor 231a' and the inner middle electric conductor 232a form two adjacent layer coil ends arranged on different concentric circles. You.

Further, as shown in FIG. 3, the electric conductor 231a of the inner end layer and the electric conductor 231b of the outer end layer are formed by forming a series of electric conductors into a substantially U-shaped large segment 23.
1 provided. Then, the electric conductor 232 of the inner middle layer
a and the outer middle electrical conductor 232b are provided by a small segment 232 formed by forming a series of electrical conductors in a generally U-shape. The basic U-shaped conductor segment 23 is formed by a large segment 231 and a small segment 232. Each of the segments 231 and 232 has a portion that is accommodated in the slot 25 and extends along the axial direction, and also has a skewed portion 23 that extends at a predetermined angle with respect to the axial direction.
1f, 231g, 232f, and 232g. By these skewed portions, coil ends protruding from the stator core 22 at both axial end surfaces are formed, and the cooling fans 11 and 12 attached to both axial end surfaces of the rotor 3 are formed.
The ventilation path of the cooling air generated when the is rotated is mainly formed between these oblique portions.

The above configuration is repeated for each conductor segment 23 of all the slots 25. Then, at the coil end opposite to the turn portions 231c and 232c, the tip 231e 'of the conductor segment 23 in the outer end layer, the tip 232e of the conductor segment 23 in the outer middle layer, and the tip 232d of the conductor segment 23 in the inner middle layer. And the tip portion 231d 'of the conductor segment 23 of the inner end layer are joined by means of welding, ultrasonic welding, arc welding, brazing, or the like, and are electrically connected.

In the stator 2 manufactured as described above, each conductor segment 23 for one phase as viewed from the inner peripheral side of the stator core 22 is shown in FIG.
5C and 5C are perspective views of the coil end group on the opposite side to FIG.
Is shown in

In the first coil end group 21a corresponding to the turn portions 231c and 232c, the middle coil end and the end layer coil end are the basic coil ends. Further, in the second coil end group 21b opposite to the turn portions 231c and 232c, the adjacent layer coil end is the basic coil end. And a plurality of basic coil ends are arranged regularly and repeatedly. A gap is secured between all coil ends. In addition, the respective basic coil ends are distributed at a substantially constant density in the circumferential direction in the annular coil end group.

The inner peripheral surfaces of both coil end groups 21a and 21b are formed to have an inner diameter slightly larger than the inner peripheral surface of stator core 22. Further, both coil end groups 21
a and 21b have a substantially constant height over the entire circumference.

Next, a process of manufacturing the conductor segment 23 constituting the stator winding 21 will be described. 6 to 10
FIG. 7 is a perspective view illustrating a manufacturing process of the conductor segment 23. First, the linear conductor segment 23 having a predetermined length corresponding to the large segment 231 and the small segment 2
And a linear conductor segment 23 having a predetermined length corresponding to the slot 32 of the stator core 22.
Prepare as many as.

Next, the linear conductor segment 23 having a predetermined length corresponding to the small segment 232 is bent at substantially the center and processed into a V-shape (FIG. 6). In this step of processing the small segment 232, the angle at which the conductor segment 23 is bent so as to be V-shaped is adjusted. By this step, a turn portion 232c having a predetermined radius of curvature is formed, and the distance increases from the turn portion 232c toward the tip. In addition, let a be the outer space | interval of the front-end | tip part of this small segment 232 formed in V shape.

Next, the linear conductor segment 23 having a predetermined length corresponding to the large segment 231 is bent substantially at the center and processed into a U-shape (FIG. 7). In this step of processing the large segment 231, the bending angle is adjusted so that the conductor segment 23 becomes U-shaped. By this step, a turn portion 231c having a radius of curvature larger than the radius of the bent portion of the V-shaped small segment 232 described above is formed, and the two straight portions bent by the turn portion 231 become substantially parallel. In addition,
Let b be the inner space between the ends of the large segment 231 formed in a U-shape. The relationship a> b exists between the outer distance a at the distal end of the small segment 232 and the inner distance b at the distal end of the large segment 231 described above.

Next, the large segment 231 is arranged outside the small segment 232 (FIG. 8). As described above, the outer interval a at the distal end of the small segment 232 is wider than the inner interval b at the distal end of the large segment 231, and the distal end of the small segment 232 has a V-shaped shape. Since the elastic force to be maintained and the force pushed by the U-shaped large segment 231 arranged on the outside work, the tip of the small segment 232 is securely attached to the tip of the large segment 231 as shown in FIG. , And the distal ends of the small segments 232 are separated from each other. The step shown in FIG. 8 described above is the “first step” in the present invention.
It corresponds to.

Thereafter, the state where the small segment 232 and the large segment 231 are overlapped (the state shown in FIG. 8) is maintained, and the small segment 232 and the large segment 231 are maintained.
Is adjusted to a predetermined value, and both ends of these two segments 231 and 232 are fixed by twisting jigs 300 and 310, respectively (FIG. 9), and the twisting jig 300 is divided into two segments. The torsion jig 310 is moved in the direction perpendicular to the bending direction of the 231 and 232 by the half magnetic pole pitch, and the torsion jig 310 is moved to the opposite direction to the torsion jig 300 by the demagnetizing pole pitch (FIG. 10). Thereby, the large segment 231 and the small segment 232 are simultaneously twist-formed. The steps shown in FIGS. 9 and 10 correspond to the “second step” and the “third step” in the present invention.

The segments 231 and 232 thus formed are inserted into the slots 25 of the stator core 22 while being assembled (FIG. 11). The step shown in FIG. 11 corresponds to the “fourth step” in the present invention. In FIG. 11, the shape of the opening side of the slot 25 is simplified and the insulator 24 is omitted in order to make it easier to understand how the segments 231 and 232 are inserted into the slot 25. However, in practice, the slot 25 has a shape as shown in FIG. 2 described above, and the insulator 24 is interposed between each segment 231 and 232 and the wall surface of the slot 25.

Each of the segments 231 and 232 is provided with a turn portion 231c, 23 on the same side of the axial side surface of the stator core 22.
2c are inserted into the slot 25 so as to be aligned. At this time, the two straight portions included in each of the segments 231 and 232 are accommodated in different slots 25 separated by one magnetic pole pitch.

Next, as shown in FIG. 5 described above, the tip portions 231d ', 232d, 232 located on the side opposite to the turn portion side.
e, 231e ′ are twisted in opposite circumferential directions, and then the tip 231d ′ corresponding to the conductor in the inner end layer and the tip 232d corresponding to the conductor in the inner middle layer are joined by welding or the like. The tip 232e corresponding to the conductor and the tip 231e 'corresponding to the conductor in the outer end layer are joined by welding or the like. The joints of the segments 231 and 232 thus formed are formed such that the heights from the stator core 22 are substantially the same. The steps described above
This corresponds to the “fifth step” in the present invention.

As described above, in the automotive alternator 1 of the present embodiment, when the stator 2 is manufactured, the large segment 231 formed into a U shape is formed outside the small segment 232 formed into a V shape. After placing these segments 231,
The conductor segments 23 are formed by simultaneously twist-forming the 232 in a combined state. Since the outer interval a at the distal end of the small segment 232 formed in a V shape is wider than the inner interval b at the distal end of the large segment 231 formed in a U shape, at the distal end of the small segment 232, Since the elastic force for maintaining the V-shape and the force for pressing the large U-shaped segment 231 disposed on the outside work, the tip of the small segment 232 and the large segment 231 reliably contact each other. At the same time, an effect is obtained that the distal ends of the small segments 232 are separated from each other.
In addition, the small segment 232 and the large segment 231 are kept in a combined state even after being formed by twisting, and these segments are simultaneously inserted into predetermined slots provided in the stator core, so that the stator winding 21 is formed. Is formed. Therefore, each segment 231, 232
Are inserted into the slots of the stator core 22, or after the respective tips of the small segments 232 are twisted in opposite circumferential directions, adjacent tips of the small segments 232 come into contact with each other. Small segments 232 as encapsulated conductor segments 23
The distance between the tip portions and the insulating state can be ensured.
Further, since it is not necessary to insert an insulating material or the like to secure an insulating state, the number of parts does not increase.

The present invention is not limited to the above embodiment, and various modifications can be made within the scope of the present invention. For example, in the above-described embodiment, as shown in FIGS. 9 and 10, the twisting jigs 300 and 310 are used for a set of conductor segments formed by disposing the small segment 232 inside the large segment 231. Although the twisting is performed, a plurality of sets of conductor segments may be overlapped and arranged in parallel, and the plurality of sets of conductor segments may be simultaneously twisted. FIG.
In the above description, a case has been described in which one set of the conductor segments 23 subjected to the twisting process is inserted into the slots 25 of the stator core 22. However, a plurality of sets of the conductor segments 23 may be inserted into a predetermined number of slots 25 at the same time. Good. Thus, a plurality of sets of conductor segments 23 are simultaneously twisted and formed,
A predetermined number of slots 25 provided in the stator core 22
At the same time, it is possible to reduce the number of man-hours in manufacturing the stator 2,
Overall cost can be reduced.

Further, in the above-described embodiment, the winding forming method of the present invention has been described by taking the stator of the vehicle alternator as an example. The present invention can be applied to a case where a child winding is formed using a conductor segment.

[Brief description of the drawings]

FIG. 1 is a diagram showing an overall configuration of an automotive alternator.

FIG. 2 is a partial sectional view of a stator.

FIG. 3 is a perspective view of a segment constituting a stator winding.

FIG. 4 is a partial side view of a stator winding developed and viewed from the inner peripheral side.

FIG. 5 is a partial perspective view of a stator.

FIG. 6 is a perspective view showing a manufacturing process of a conductor segment before assembling to a stator.

FIG. 7 is a perspective view showing a manufacturing process of a conductor segment before assembling to a stator.

FIG. 8 is a perspective view showing a manufacturing process of a conductor segment before assembling the stator.

FIG. 9 is a perspective view showing a manufacturing process of a conductor segment before assembling to a stator.

FIG. 10 is a perspective view showing a manufacturing process of a conductor segment before assembling to a stator.

FIG. 11 is a perspective view showing a manufacturing process when assembling a conductor segment to a stator.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Vehicle alternator 2 Stator 3 Rotor 22 Stator core 23 Conductor segment 231 Large segment 232 Small segment 25 slot

 ──────────────────────────────────────────────────続 き Continued on the front page F term (reference) 5H603 AA09 BB02 BB05 BB12 CA01 CA05 CB03 CC05 CC11 CC17 CD06 CD22 CE02 EE01 5H615 AA01 BB02 BB05 BB14 PP01 PP14 QQ03 SS05 SS16

Claims (4)

[Claims] 1. A first step of arranging a substantially U-shaped second conductor segment outside a substantially V-shaped first conductor segment; and the first and second conductors. A second step of setting the distance between the distal ends of the first conductor segments to a predetermined value in a state where the segments are combined; and a third step of simultaneously twist-forming the first and second conductor segments. A fourth step of simultaneously inserting the first and second conductor segments into slots formed in the laminated core. 2. The first conductor segment according to claim 1, wherein an interval of the first conductor segment increases from a turn portion to a tip portion, and the second conductor segment is formed substantially parallel from the turn portion to the tip portion. In a state before the first and second conductor segments are combined, the tip interval of the first conductor segment is set to be wider than the tip interval of the second conductor segment. Characteristic winding forming method. 3. The laminated core according to claim 1, wherein a portion from a turn portion to a tip portion of each of the first and second conductor segments is formed in an annular shape by the third step. The inner and outer ends of the first and second conductor segments projecting from different slots and the first and second projecting segments projecting from different slots after being arranged separately on the inner diameter side and the outer diameter side of the A fifth step of joining the outer peripheral ends of the conductor segments to each other. 4. The method according to claim 1, wherein a plurality of combinations of the first and second conductor segments are formed in the first step, and the first and second conductor segments are formed in the third step. A method for forming a winding, wherein the conductor segments are simultaneously twist-formed, and in the fourth step, the first and second conductor segments are simultaneously inserted into the slots of the laminated core.