JP4114282B2 - Rotating electric machine and manufacturing method thereof - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a rotating electrical machine having a pine needle conductor sequential connection type stator coil, for example, a rotating electrical machine suitable as an AC generator for a vehicle.
[0002]
[Prior art]
WO92 / 06527 and WO98 / 54823 disclose a rotating electric machine having a pine needle conductor sequential connection type stator coil.
[0003]
This rotating electrical machine has a stator coil formed by sequentially connecting the tips of a number of pine needle conductors inserted through a number of slots formed in the axial direction in the vicinity of the inner peripheral surface of a cylindrical stator core. Each of the conductors has a shape in which both base ends of a pair of leg portions are connected by curved heads and is covered with an insulating resin layer, and the leg portions are individually paired into a pair of slots. A slot conductor portion and a tip-side protruding portion that protrudes from the tip end of the slot conductor portion to one end side in the axial direction of the stator core and forms a part of a coil end on one end side of the stator coil. Projecting from the base end to the other axial end side of the stator core forms a part of the coil end on the other end side of the stator coil. Such a pine needle conductor is called a U-shaped or V-shaped conductor segment.
[0004]
[Problems to be solved by the invention]
In the rotating electrical machine having the conventional pine needle conductor sequential connection type stator coil described above, the present inventors bent the conductor into a U-shape when forming the head of the pine needle conductor, and then, after that, the pine needle conductor Because the head is bent again to widen the pair of legs by the circumferential span, strong stress is applied to the insulating resin layer on the head of the pine needle conductor, causing the insulating resin layer to break or peel from the conductor As a result, it has been found that problems such as rare earth and electric leakage may occur between the stator core and the frame for fixing the stator core.
[0005]
The present invention has been made in view of the above problems, and an object of the present invention is to provide a rotating electrical machine having a pine needle-like conductor sequential connection type stator coil excellent in electrical insulation reliability.
[0006]
[Means for Solving the Problems]
  The rotating electrical machine according to claim 1, which has been made to solve the above problems.Has a stator coil formed by sequentially connecting the tips of a large number of pine needle conductors inserted through a large number of slots formed in a cylindrical stator core, and the pine needle conductors are separated into a pair of slots. In a rotating electrical machine having a shape in which both base ends of a pair of leg portions inserted into the U-shaped heads are connected to the outside of the slot and covered with an insulating resin layer, the outer diameter is at the end portion. The largest radial gap length between a pair of conductors having a Landel type rotor core having a gradually decreasing diameter and a brush disposed on the other axial end side of the stator core and supplying power to the rotor coil, constituting the head Is formed to be larger than the maximum radial gap length between the pair of legs constituting the pine needle conductor together with the head, and the legs are individually accommodated in the pair of slots. Lots conductor portion made with the slot conductor portion of the distal side projection tip from projecting in the axial direction one end side of the stator core forming a part of the coil end of one end of the stator coil,
The head portion protrudes from the base ends of the slot conductor portions to the other axial end side of the stator core to form a part of a coil end on the other end side of the stator coil. The inner diameter of the stator core is biased toward the inner diameter of the stator core than the slot conductors connected to each other, the inner diameter of the coil end on the other end side is formed to be equal to or smaller than the inner diameter of the stator core, and the inner diameter of the coil end on the other end side is With a predetermined gap with respect to the Landel rotor core, the diameter gradually decreases as the distance from the end surface of the stator core increases, and the minimum inner diameter of the coil end on the other end side is smaller than the maximum outer diameter of the rotor core, The inner diameter of the coil end on one end side is characterized by being formed larger than the outer diameter of the Landel rotor core.
[0007]
In this configuration, in particular, the maximum radial gap length at the head of the pine needle conductor is made larger than the maximum radial gap length at the leg portion of the pine needle conductor. That is, each pine needle-like conductor is formed such that its head is wider in the radial direction than its leg portion, particularly the slot insertion portion (slot conductor portion).
[0008]
  In this way, one head is bent and this head is bent.PartWhen forming, since the radius of curvature can be made larger than before, the stress applied to the insulating resin layer covering the head is reduced accordingly. Therefore, according to this configuration, the insulating resin layer can be prevented from being broken and its electrical insulation can be improved.
[0009]
In the past, the maximum radial gap length at the head of the pine needle conductor was set equal to that between both legs.
[0010]
  In a preferred embodiment,A square conductor having a square cross section is used as the pine needle conductor.
[0011]
In this way, the slot space factor can be improved, and the insulating resin layer can be well prevented from being broken even when a rectangular conductor that tends to increase stress (especially tensile stress) of the insulating resin layer during bending is used. it can.
[0012]
  In the present invention,The leg portions are a pair of slot conductor portions individually accommodated in the slots, and projecting from the tip ends of these slot conductor portions toward one end side in the axial direction of the stator core to form a part of a coil end on one end side of the stator coil. It consists of parts. Further, the head portion projects from the proximal end of both slot conductor portions to the other axial end side of the stator core and forms a part of the coil end on the other end side of the stator coil.
[0013]
In particular, in this configuration, the head is formed so as to be biased inward of the diameter of the stator core with respect to the slot conductor portion connected to the head.
[0014]
In this way, since the radius of curvature in the radial direction of the head can be increased and bent gently, damage and deterioration of the insulating resin layer on the head can be further suppressed.
[0015]
  In the present invention,Since the inner diameter of the coil end on the other end side is formed to be smaller than the inner diameter of the stator core, it is possible to satisfactorily prevent the insulating resin layer of the coil end on the other end side from being broken during bending without increasing the size of the frame. be able to. The inner diameter here refers to the distance from the axis of the rotating shaft.
[0016]
  In the present invention,In a rotating electrical machine (ie, a vehicle AC generator) having a Randell type rotor core whose outer diameter gradually decreases from the end surface on the head side of the stator core to the side opposite to the stator core (which becomes a taper surface), The inner diameter of the coil end gradually decreases with increasing distance from the end face of the stator core, with a predetermined gap from the Landel rotor core, and the minimum inner diameter of the coil end on the other end side is smaller than the maximum outer diameter of the rotor core. The
[0017]
In this way, the space earned by using the shoulder portion of the rotor core as a taper surface can be used to increase the radius of curvature of the head portion of the pine needle conductor, so that the head portion can be increased without increasing the diameter of the frame. It is possible to prevent the insulating resin layer from being broken.
[0018]
  In the present invention,Since it has a brush that is arranged on the other axial end side of the stator core and feeds power to the rotor coil, the coil end on one end side connecting the tip ends of each pine needle conductor is sandwiched between the rotor core and the brush. Therefore, it is possible to prevent the insulating resin layer peeling portion at the tip of the leg portion of the pine needle conductor from being creepingly discharged to other conductive portions through the brush powder.
[0019]
  In a preferred embodiment,The coil end on the other end side, that is, the coil end including the head of the pine needle conductor, has a predetermined gap with respect to the inner peripheral surface of the frame to which the stator core is fixed at the same axial position as the coil end on the other end side. Therefore, even if the insulating resin layer at the head of the pine needle conductor is deteriorated by the bending process or the like, it is possible to prevent leakage of electric current to the frame.
[0020]
  In a preferred embodiment,Since the coil end on one end side and the coil end on the other end side have substantially the same outer diameter, there is no need to increase the frame.
[0021]
  In the present invention,Since the inner diameter of the coil end on one end side is formed larger than the outer diameter of the Landel rotor core, the Landel rotor core can be inserted into the stator core from the coil end side on one end side, which can complicate the rotor core insertion work. Absent.
[0022]
  In a preferred embodiment,Since the inner diameter of the coil end on one end side is formed larger than the inner diameter of the stator core, a gap can be reliably secured between the outer peripheral surface of the rotor core and the inner peripheral surface of the coil end on one end side when the rotor core is inserted. The insulating resin layer at the coil end on one end side is not broken by the rotor core during insertion.
[0023]
  In a preferred embodiment,First, a pine needle-shaped conductor having a minimum inner radius of curvature of the head larger than half the minimum gap length between the pair of legs is manufactured, and then the circumferential spans of the pair of both conductors constituting the head of the pine needle conductor are measured. Enlarge to provide the necessary circumferential span between the legs, after which the legs are individually inserted into a pair of slots. These two leg portions are inserted into different slot conductor insertion positions among a plurality of slot conductor insertion positions set adjacent to each other in the radial direction in the slot.
[0024]
Therefore, according to this configuration, before the pine needle conductor is expanded in the circumferential span, the minimum inner radius of curvature of the head is previously set to be larger than half the minimum gap length between the pair of legs. The stress of the insulating resin layer at the time of expansion can be reduced.
[0025]
  In a preferred embodiment,The minimum inner radius of curvature r of the head portion of at least a portion of the pine needle conductor is in the range of 0.43 t to 0.55 t with respect to the thickness t of the leg portion in the gap direction (in the curved surface) between the two leg portions. Set to
[0026]
According to the experiment, the minimum inner curvature radius r of the head is set to be sufficiently large as 0.43 t or more as compared with the thickness of the leg, so that the stress of the insulating resin layer in the head can be reduced satisfactorily. When the head is less than 55 t, the head is prevented from becoming extremely large in the radial direction, so that the head can be prevented from coming into contact with the inner peripheral surface of the frame that supports the stator core.
[0027]
DETAILED DESCRIPTION OF THE INVENTION
Hereinafter, a vehicle AC generator as a rotating electrical machine to which the present invention is applied will be described based on each embodiment shown in the drawings.
[0028]
[Example 1]
FIGS. 1 to 7 show a first embodiment of the present invention. FIG. 1 is a cross-sectional view of a main part of an AC generator for a vehicle. FIGS. 2 to 7 are explanatory views of a stator according to this embodiment. .
(Overall explanation)
The vehicle alternator 1 includes a rotor 2 that functions as a field element, a stator 3 that functions as an armature, a rotor 2 that rotatably supports the stator 3, and is fixed by fastening bolts 4c while sandwiching the stator 3. Front housing 4a and rear housing 4b, and a rectifier 5 for converting AC power into DC power.
[0029]
The rotor 2 rotates integrally with the shaft 6. The rotor 2 is a Landel pole core (Landel rotor core) 7, a field coil 8, slip rings 9, 10, a mixed flow fan 11 as a blower, and a centrifugal fan 12. It has. Reference numerals 13 and 14 denote brushes for supplying power to the field coil 8 through the slip rings 9 and 10.
[0030]
The stator 3 includes a stator winding (stator coil) 31 and a stator core (stator core) 32. The stator core 32 is sandwiched and fixed between the front housing 4a and the rear housing 4b.
[0031]
The shaft 6 is connected to a pulley 20 and is driven to rotate by a traveling engine (not shown) mounted on the automobile.
[0032]
The Landel-type pole core 7 is configured by combining a pair of pole cores. The Landel-type pole core (rotor core) 7 includes a boss part 71 assembled to the shaft 6, a disk part 72 extending in the radial direction from both ends of the boss part 71, and twelve claw-shaped magnetic pole parts 73.
[0033]
The Landel-type pole core 7 has a shape that gradually decreases in diameter as it moves away from the end face of the stator core 32 of the stator (stator) 3 (the outer peripheral end approaches the axis of the rotor 2).
[0034]
Of the pair of coil ends 36, 37 of the stator winding (stator coil) 31, the inner diameter of the first coil end 36 (coil end on the other end side) projecting to the rear side has a predetermined gap with respect to the pole core 7. The diameter gradually decreases as the distance from the end face of the stator core 32 increases. Further, as shown in FIG. 7, the minimum inner diameter Ro of the first coil end 36 (coil end on the other end side) is smaller than the maximum outer diameter Rr of the pole core 7, and the first coil end 36 has a diameter of the stator core 32. It is formed so as to be biased inward. In this way, the curvature radius in the radial direction of the heads of the crutch-like conductors 38 and 39 constituting the coil end 36 can be increased and bent gently, so that the insulating resin layer on the head is not damaged or deteriorated. It can be further deterred.
[0035]
The pulley-side mixed flow fan 11 has a blade having an acute inclination with respect to the base plate 111 fixed to the end surface of the pole core by welding or the like, and a blade perpendicular to the base plate 111, and is integrated with the rotor 2. Rotate. The centrifugal fan 12 on the side opposite to the pulley has only a blade perpendicular to the base plate 121 fixed to the end face of the pole core 7 by welding or the like.
[0036]
Cooling air suction holes 41 are provided in the axial end surface of the front housing 4a, and the first coil end (the coil on the other end side) of the stator coil of the stator 3 is provided on both outer shoulders of the rear housing 4b and the front housing 4a. Ends 36 and a second coil end (one end side coil end) 37 are provided in close proximity to each other to provide cooling air discharge holes 42.
[0037]
The rectifier 5 is provided at the end on the side opposite to the pulley of the vehicle alternator 1. Accordingly, the first coil end 36 is disposed in association with the rectifier 5.
(Description of the stator winding 31)
A radial cross section of the stator 3 is shown in FIG. 2 for two slots, and a schematic perspective view of a pair of pine-shaped conductors 38 and 39 constituting the stator winding 31 is shown in FIG.
[0038]
The stator core 32 has a number of slots 33 for receiving multiphase stator windings. Reference numeral 34 denotes an insulator that electrically insulates between the stator core 32 and the stator winding 31 in the slot 33. In the present embodiment, 36 slots 33 are formed at equal intervals in order to accommodate three-phase stator windings corresponding to the number of magnetic poles of the rotor 2. Each slot 33 is provided with an even number (4 in this embodiment) of slot conductor portion receiving positions C1, C2, C3, C4 in order from the radially inner side to the radially outer side.
[0039]
The stator winding 31 includes a slot conductor portion 35 accommodated in the slot 33, a first coil end 36 projecting from the slot conductor portion 35 to the outside of the slot and extending to the rear side, and from the slot conductor portion 35 to the outside of the slot. The second coil end 37 protrudes to the side, and is configured using a large number of large pine-shaped conductors 38 and small pine-shaped conductors 39 each of which is a rectangular conductor.
[0040]
As shown in FIG. 3, the large pine needle conductor 38 includes a substantially U-shaped head portion 380 constituting the first coil end 36 and a pair of leg portions 381 and 382 extending from both ends of the head portion 380. It consists of. The head 890 has a circumferential span with a predetermined magnetic pole pitch at the joints with the legs 381 and 382.
[0041]
The leg portion 381 includes a slot conductor portion 3811 accommodated in the slot conductor insertion position C1 of the slot 33, and a tip side protruding portion 3812 that protrudes from the slot conductor portion 3811 to the front side and constitutes the second coil end 37. The tip side protruding portion 3812 has a joint portion 3813 at the tip thereof.
[0042]
The leg portion 382 includes a slot conductor portion 3821 accommodated in the slot conductor insertion position C4 of the slot 33, and a tip side protruding portion 3822 that protrudes from the slot conductor portion 3821 to the front side and constitutes the second coil end 37. The tip side protruding portion 3822 has a joint portion 3823 at the tip thereof.
[0043]
The proximal end (slot conductor portion side) and the distal end of the distal-side protruding portion 3812 and the proximal end (slot conductor portion-side) and the distal end of the distal-side protruding portion 3822 are approximately half of the circumferential span of the head 380 in the circumferential direction. The distance is.
[0044]
As shown in FIG. 3, the small pine needle-shaped conductor 39 includes a substantially U-shaped head portion 390 constituting the first coil end 36 and a pair of leg portions 391 and 392 extending from both ends of the head portion 390. It consists of. The head 390 has a circumferential span with a predetermined magnetic pole pitch at the joints with the legs 391 and 392.
[0045]
The leg portion 391 includes a slot conductor portion 3911 accommodated in the slot conductor insertion position C2 of the slot 33, and a tip side protruding portion 3912 that protrudes from the slot conductor portion 3911 to the front side and constitutes the second coil end 37. The tip side protruding portion 3912 has a joint portion 3913 at the tip thereof.
[0046]
The leg portion 392 includes a slot conductor portion 3921 accommodated in the slot conductor insertion position C3 of the slot 33, and a tip side protruding portion 3922 that protrudes from the slot conductor portion 3921 to the front side and constitutes the second coil end 37. The tip side protrusion 3922 has a joint 3923 at the tip.
[0047]
The proximal end (slot conductor portion side) and the distal end of the distal-side protruding portion 3912 and the proximal end (slot conductor portion side) and the distal end of the 3922 are separated from each other by a distance of about half of the circumferential span of the head 390 in the circumferential direction. ing.
[0048]
A pair of leg portions 381 and 382 of the same large pine-shaped conductor 38, more specifically, the slot conductor portions 3811 and 3821 are separately accommodated in different slots 33 which are separated by a predetermined magnetic pole pitch. The pair of leg portions 391 and 392 of the pin-shaped pine needle conductor 39, more specifically, the slot conductor portions 3911 and 3921 are separately accommodated in different slots 33 that are separated by a predetermined magnetic pole pitch.
[0049]
As already described, the slot conductor portion 3811 of the leg portion 381 of the large-circle-shaped pine needle conductor 38 is accommodated in the shallowest slot conductor insertion position C1 of the slot 33, and the slot of the leg portion 382 of the large-circle-shaped pine needle conductor 38 is accommodated. The conductor portion 3821 is accommodated in the deepest slot conductor insertion position C4.
[0050]
Similarly, the slot conductor portion 3911 of the leg portion 391 of the small pine-shaped conductor 39 is accommodated in the second shallowest slot conductor insertion position C2 of the slot 33, and the slot conductor of the leg 392 of the small pine-shaped conductor 39 is formed. The portion 3921 is accommodated in the third shallowest slot conductor insertion position C3.
[0051]
As a result, in the first coil end 36 on the rear side, the head 380 of the large crutch-shaped conductor 38 can be disposed so as to wrap the head 390 of the small crutch-shaped conductor 39, and both heads 380, 390 intersect. Interference is prevented.
[0052]
More specifically, in the first coil end 36 on the rear side, the head portion 380 includes a slot conductor portion 3811 of the leg portion 381 inserted into the slot conductor insertion position C1 and a leg portion 382 inserted into the slot conductor insertion position C4. The slot conductor portion 3821 is connected. The head portion 390 connects the slot conductor portion 3911 of the leg portion 391 inserted at the slot conductor insertion position C2 and the slot conductor portion 3921 of the leg portion 392 inserted at the slot conductor insertion position C3.
[0053]
In the second coil end 37 on the front side, the tip side protruding portion 3812 of the leg portion 381 of the pine needle conductor 38 at the C1 position has a leg portion of the pine needle conductor 39 at the C2 position adjacent in the radial direction at the tip thereof. It joins with the front end side protrusion part 3912 of 391. Similarly, the tip side protruding portion 3822 of the leg portion 382 of the pine needle conductor 38 at the C4 position is joined to the tip side protruding portion 3922 of the leg portion 392 of the pine needle conductor 39 at the C3 position adjacent to the radial direction at the tip thereof. Is done.
[0054]
That is, the slot conductor portion 3811 of the leg portion 381 inserted at the slot conductor insertion position C1 is connected to the slot conductor portion 3911 of the leg portion 391 inserted at the slot conductor insertion position C2 at the second coil end 37 on the front side. Is done. Further, the slot conductor portion 3821 of the leg portion 382 inserted at the slot conductor insertion position C4 is connected to the slot conductor portion 3921 of the leg portion 392 inserted at the slot conductor insertion position C3 at the second coil end 37 on the front side. Is done. Thereby, a three-phase stator winding 31 is formed. A part of the second coil end 37 on the front side is shown in FIG.
[0055]
However, the slot conductor portion and a part of the slot conductor portion constituting the lead wire of the stator winding 31 are formed in a shape different from those of the pine needle conductors 38 and 39. In other words, the first coil end 36 on the rear side has a special pine needle shape having a deformed head portion that connects the slot conductor portions at the slot conductor insertion positions C1 and C4 and the slot conductor portions at the slot conductor insertion positions C2 and C3. A conductor is provided.
[0056]
Since the structure itself and the wiring format itself of this type of pine needle conductor sequential connection type are the same as those of the above-mentioned prior art, further explanation will be omitted. Therefore, it is of course possible to give various variations to the connection of the stator coil of the pine needle conductor sequential connection type. In this way, the stator winding 31 is formed.
(Characteristic configuration of stator 3)
Other characteristics of the stator 3 configured by the above manufacturing method will be described below with reference to an axial schematic enlarged sectional view of the stator 3 shown in FIG.
[0057]
The minimum inner diameter Ro of the first coil end 36 is formed to be smaller than the maximum outer diameter Rr of the rotor core 7 facing the first coil end 36 in the radial direction, and of course, smaller than the minimum inner diameter Rs of the stator core 32. Formed.
[0058]
Further, the curved outer surface 395 of the head 390 of the small pine-shaped conductor 39 is opposed to the curved inner surface 385 of the head 380 of the large pine-shaped conductor 38 at the first coil end 36 with a predetermined gap.
[0059]
Further, as shown in FIG. 5, in this embodiment, the outer diameter of the outer peripheral shoulder 75 of the rotor core 7 is a so-called taper that becomes smaller as the distance from the vicinity of the rear end of the slot 33 increases toward the rear. It has a shape.
[0060]
Further, since the head portions 380 and 390 are biased to the inside of the diameter of the stator core 32 with respect to the slot conductor portions 3811 and 3911 connected to the head portions 380 and 390, the shoulder portion of the rotor core 7 serves as a taper surface. The earned space can be used to increase the curvature radius of the head portion 380 of the pine needle conductor, and the tearing of the insulating resin layer on the head portion can be suppressed (see FIG. 7).
[0061]
Moreover, since both the coil ends 36 and 37 have substantially the same outer diameter, it is not necessary to increase the frame diameter.
[0062]
Further, since the inner diameter of the second coil end 37 is formed larger than the outer shape of the Landel-type pole core 7, the Landel-type rotor core 7 can be inserted into the stator core 32 from the front side, and the rotor core insertion work is not complicated. .
[0063]
Furthermore, since the inner diameter of the second coil end 37 is formed larger than the inner diameter of the stator core 32, a gap is surely provided between the outer peripheral surface of the rotor core 7 and the inner peripheral surface of the second coil end 37 when the rotor core 7 is inserted. The insulating resin layer of the coil end 37 is not broken by the rotor core 7 when the rotor core 7 is inserted.
[0064]
The surface on the inner diameter side of the outer head portion 380 bulges radially inward from the slot 33 and substantially parallel to the outer peripheral surface of the taper-shaped outer peripheral shoulder 75. Thereby, the radius of curvature in the radial direction of the first coil end 36, more specifically, the heads 380 and 390 can be set large, and the stress of the insulating resin layer in the first coil end 36 can be reduced and the breakage can be suppressed well. can do.
[0065]
Further, according to this embodiment, the minimum inner radius of curvature r of the head portion 390 of the pine needle conductor 39 is, as shown in FIG. 5, the leg portion in the gap direction (in the curved surface) between the both leg portions 391 and 392. Is set in a range of 0.43T to 0.55T.
[0066]
According to the experiment, the minimum inner curvature radius r of the head is set to be sufficiently larger than 0.43 T as compared with the thickness t of the legs 391 and 392, so that the stress of the insulating resin layer in the head 390 is reduced well. As well as being less than 0.55T, the head portion 390 is prevented from increasing in the radially outward direction, so that the head portion 390 is prevented from contacting the inner peripheral surface of the rear housing 4b that supports the stator core 32. be able to.
(Description of manufacturing process of stator winding 31)
A manufacturing process of the stator winding 31 will be described below.
[0067]
(1) Manufacture of pine needle conductors 38 and 39
First, a rectangular conductor wire covered with an insulating resin layer is cut to a predetermined length, and the insulating resin layers at both ends are peeled off, and then bent to produce pine needle conductors 38 and 39, respectively. FIG. 5 shows a partial side view of the vicinity of the head 390 of the small pine-shaped conductor 39, and FIG. 6 shows a partial side view of the vicinity of the head 380 of the large pine-shaped conductor 38.
[0068]
The gap width D0 between the leg portions 381 and 382 of the large-circular pine needle conductor 38 is made smaller than the maximum gap width D1 of the head 380 of the pine needle conductor 38 in the same direction as this gap width. Therefore, in the direction of the gap width D0, the overall width D2 of the legs 381, 382 of the pine needle conductor 38 is approximately D0 + 2T, the overall width D3 of the head 380 of the pine conductor 38 is approximately D1 + 2T, and D3> D2. It has become. T is the thickness of the pine needle conductor 38 in the direction of the gap width D0.
[0069]
Similarly, the gap width D0 ′ between the leg portions 391 and 392 of the small pine-shaped conductor 39 is made smaller than the maximum gap width D1 ′ of the head 390 of the pine-shaped conductor 39 in the same direction as this gap width. The Accordingly, in the direction of the gap width D0 ′, the overall width D2 ′ of the legs 391 and 392 of the pine needle conductor 39 is substantially D0 ′ + 2T, and the overall width D3 ′ of the head 390 of the pine needle conductor 39 is substantially D1 ′. + 2T, and D3 ′> D2 ′. T is the thickness of the pine needle conductor 39 in the direction of the gap width D0 '. Actually, the gap width D 0 ′ is almost 0, and T is a value slightly smaller than the width between two adjacent slot conductor insertion positions in the slot 33.
[0070]
At this stage, the pair of leg portions 381 and 382 of the pine needle conductor 38 overlap when projected in the direction of the gap width D0, and the pair of leg portions 391 and 392 of the pine needle conductor 39 overlap with the gap width D0 ′. When projected in the direction of.
[0071]
Next, the pair of leg portions 381 and 382 of the pine needle conductor 38 opens in the circumferential direction with the center of the head 380 as a base point so that it has a predetermined circumferential span, and similarly, the pair of leg portions of the pine needle conductor 39 It opens in the circumferential direction starting from the center of the head 390 so that 391 and 392 have a predetermined circumferential span.
[0072]
At this time, one half from the center of the head 380 of the pine needle-shaped conductor 38 toward the radially inner leg 381, and the other from the center of the head 380 of the pine-shaped conductor 38 toward the radially inner leg 381. One half means that the radial position of the leg portion 381 is smaller than the radial position of the leg portion 382. One-half circumferential distance toward 381 is shorter than one-half circumferential distance toward the outer diameter leg 382. Therefore, in order to ensure this distance difference, when one half of the head 380 toward the inner diameter leg portion 381 swells radially inward, one half of the head 380 toward the outer diameter leg portion 382 returns to the original outer diameter. Consume the bulge. As a result, in the head 380, the bulge toward the outside of a half of the diameter toward the outside leg 382 is relatively reduced. This is the same for the head 390, and the bulge toward the outside of the half of the diameter toward the leg 392 of the outside of the head is relatively reduced. Of course, in consideration of the difference in the circumferential distance, a half of the head 380 bulges toward the radially outer leg 382 and a half of the bulge toward the radially inner leg 381. It is also possible to make it relatively large in advance. Similarly, in consideration of the above-described difference in the circumferential direction, the bulge of the head 390 toward the radially outer side toward the radially outer leg 392 is caused to extend toward the radially inner side toward the radially inner leg 391. It may be relatively larger than the bulge in advance.
[0073]
(2) Inserting the pine needle conductors 38 and 39 into the slots 33
Next, the leg portions 391 and 392 of the pine needle conductor 39 are individually inserted into different pairs of slots 33 that are spaced apart from each other by a predetermined magnetic pole pitch in the circumferential direction. Similarly, the leg portions 381 and 382 of the pine needle conductor 38 are They are individually inserted into a pair of different slots 33 that are separated from each other by a predetermined magnetic pole pitch in the circumferential direction.
[0074]
(3) Opening of the tip side protruding portions of the pine needle conductors 38, 39,
Next, the front end side protruding portions 3812 and 3822, which are portions protruding to the front side from the slots 33 of the leg portions 381 and 382 of the pine needle conductor 38, are bent at a predetermined pitch in the circumferential direction. The tip side protruding portions 3912 and 3922, which are portions protruding from the slots 33 of 391 and 392 to the front side, are bent at a predetermined pitch in the circumferential direction.
[0075]
As a result, the tip of the tip-side protrusion 3912 is radially adjacent to the tip of the tip-side protrusion 3812, and the tip of the tip-side protrusion 3922 is radially adjacent to the tip of the tip-side protrusion 3822.
[0076]
Next, the tip joint 3913 of the tip projection 3912 and the tip joint 3813 of the tip projection 3812, and the tip joint 3923 of the tip projection 3922 and the tip joint 3823 of the tip projection 3822 are connected. Each is welded (see FIG. 4). Thereby, the stator 3 is formed.
[Brief description of the drawings]
FIG. 1 is an axial sectional view showing an embodiment of a rotating electrical machine of the present invention.
FIG. 2 is a partial radial cross-sectional view of the stator shown in FIG.
3 is a perspective view showing a part of the stator coil shown in FIGS. 1 and 2. FIG.
4 is a perspective view showing a front side coil end of the stator coil shown in FIG. 1; FIG.
FIG. 5 is a side view showing a small pine needle conductor.
FIG. 6 is a side view showing a large pine needle conductor.
FIG. 7 is a schematic cross-sectional view in the enlarged axial direction of the stator shown in FIG. 1;
[Explanation of symbols]
2 is a rotor, 3 is a stator (stator), 4a is a front housing (frame), 4b is a rear housing (frame), 7 is a Landel pole core (Landel rotor core), and 8 is a field coil (rotor coil). , 13 and 14 are brushes, 31 is a stator winding (stator coil), 32 is a stator core (stator core), 33 is a slot, 35 is a slot conductor, 36 is a rear coil end, and 37 is a front coil end. , 38 and 39 are pine needle conductors, 380 and 390 are heads, 381 and 391 are legs, and 3811, 3812, 3911 and 3912 are slot conductors.

Claims (7)

A stator coil formed by sequentially connecting the tips of a number of pine needle conductors inserted through a number of slots formed in a cylindrical stator core;
The pine needle-shaped conductor has a shape in which both base ends of a pair of leg portions that are separately inserted into the pair of slots are connected to each other by a U-shaped head outside the slot, and is covered with an insulating resin layer. In the rotating electrical machine
A Landel rotor core having an outer diameter that gradually becomes smaller at the end, and a brush that is disposed on the other axial end of the stator core and feeds the rotor coil.
The maximum radial gap length between the pair of conductors constituting the head is formed larger than the maximum radial gap length between the pair of legs constituting the pine needle conductor together with the head ,
The leg portions are a pair of slot conductor portions individually accommodated in the pair of slots, and project from one end of the slot conductor portion to one axial end side of the stator core and one end of a coil end on one end side of the stator coil. It consists of a tip side protruding part that forms a part,
The head portion protrudes from the base ends of the two slot conductor portions to the other axial end side of the stator core to form a part of a coil end on the other end side of the stator coil,
The head is biased to the inner diameter of the stator core from the slot conductor portion connected to the head,
The inner diameter of the coil end on the other end side is formed below the inner diameter of the stator core,
The inner diameter of the coil end on the other end side gradually becomes smaller as the distance from the end face of the stator core increases, with a predetermined gap from the Landel rotor core.
The minimum inner diameter of the coil end on the other end side is smaller than the maximum outer diameter of the rotor core,
The rotating electrical machine according to claim 1, wherein an inner diameter of the coil end on the one end side is formed larger than an outer diameter of the Landell rotor core . The rotating electrical machine according to claim 1, wherein
The rotating electric machine characterized in that the pine needle conductor has a square cross section . In the rotating electrical machine according to claim 1 or 2 ,
The coil end on the other end side is disposed with a predetermined gap from the inner peripheral surface of the frame to which the stator core is fixed at the same axial position as the coil end on the other end side. A rotating electric machine that is characterized. In the rotating electrical machine according to claim 3 ,
The rotating electric machine according to claim 1, wherein the coil end on the one end side and the coil end on the other end side have substantially the same outer diameter . The rotating electrical machine according to claim 1 , wherein
An inner diameter of the coil end on the one end side is formed larger than an inner diameter of the stator core. In the manufacturing method of the rotary electric machine according to any one of claims 1 to 5 ,
After creating a pine needle-like conductor in which the minimum inner radius of curvature of the head is larger than half of the minimum gap length between the pair of legs, the circumferential span of the two conductors constituting the head of the pine needle conductor A necessary span in the circumferential direction is provided between the two leg portions by enlarging the two, and then the both leg portions are inserted into the slots. In the manufacturing method of the rotary electric machine according to claim 6 ,
The minimum inner radius of curvature r of the head of at least a part of the pine needle conductor is set in a range of 0.43 t to 0.55 t with respect to the thickness t of the leg in the gap direction between the legs. The manufacturing method of the rotary electric machine characterized by the above-mentioned.

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