JP4665688B2 - U-segment sequential joining stator coil - Google Patents

Description

  The present invention relates to an improved manufacturing method of a U-segment sequential joining stator coil used in a rotating electrical machine.

  A U-segment sequential joining stator coil has been proposed and put to practical use as a stator coil for an AC generator for a vehicle, for example. The following Patent Documents 1 to 21 are part of a U-segment sequential joining stator coil filed by the present applicant. In this U-segment sequential joining stator coil, a pair of leg portions of a U-shaped conductor are individually inserted into a slot spaced approximately one magnetic pole pitch of the stator core from one end surface side of the stator core, and for each phase on the other end surface side of the stator core. Configured in series connection.

  The U-shaped conductor includes a U-shaped head tip portion, a pair of head skew portions individually extending from both ends of the head tip portion, and a pair of head skew portions extending from the pair of head skew portions. A pair of slot conductor portions individually accommodated in the slot, a pair of end skew portions extending individually from the pair of slot conductor portions, and a distal end portion of the end skew portion, and another U It consists of the edge part front-end | tip part (joining part) joined to the front-end | tip part of the edge part skew part of a character conductor.

  The head tip portion and the head skew portion constitute a head-side coil end, and the head skew portion and the end tip portion constitute an end-side coil end. The slot conductor portion, the head skew portion, and the end tip portion constitute a leg portion. Each slot has an even number of conductor receiving positions in the radial direction. A pair of slot conductor portions of each U-shaped conductor are accommodated in different conductor accommodation positions. The slot conductor portions of the pair of U-shaped conductors whose end tips are joined to each other are housed in different housing positions. In order to separate the pair of slot conductor portions of one U-shaped conductor by approximately one magnetic pole pitch, the head skew portion and the head skew portion of the U-shaped conductor are bent in the circumferential direction. In a typical manufacturing method, each head skew portion and head skew portion are skewed in the circumferential direction by substantially a semi-magnetic pole pitch.

  In order to develop the head skew portion of the U-shaped conductor in the circumferential direction, the head skew portion of the undeveloped U-shaped conductor formed in a pine needle shape is relatively twisted by one magnetic pole pitch. In the circumferential twisting (expansion) of the pair of head skew portions of the U-shaped conductor, the slot conductor portion planned portions of the U-shaped conductor are held by a pair of rings (also referred to as a rotating ring or a twisting ring). On the other hand, this pair of rings is realized by relative rotation of one magnetic pole pitch. More specifically, a pair of head skew portions of the U-shaped conductor are developed in the circumferential direction by rotating relative to each other while holding the slot conductor portion of the pine needle-shaped undeveloped U-shaped conductor. A head unfolding step that is performed with the skew portion is executed.

  Similarly, in order to expand the end skew portion of the U-shaped conductor in the circumferential direction, after inserting the slot conductor portion of the U-shaped conductor in which the head skew portion is expanded into the slot of the stator core, the end skew After the portion of the portion is inserted into the slot of the stator core, the pair of the end inclined portions are preliminarily rotated by rotating the pair of rings relative to each other by one magnetic pole pitch while holding the end portion of the end portion of the portion by the pair of rings. An end unfolding step is performed in which the end is skewed (deployed) to form an end skew portion. A typical coil twisting device and its operation are disclosed in, for example, Patent Literature 2, Patent Literature 20, and Patent Literature 21 below.

  A pair of slot conductor portions of one U-shaped conductor are individually accommodated in two different conductor accommodating positions. Two U-shaped conductors are connected in series by joining an end tip of one U-shaped conductor and an end tip of the other U-shaped conductor adjacent to the end tip in the radial direction. Is called. In one example, one U-segment sequential joining stator coil can be configured using two conductor receiving positions adjacent to each other in the circumferential direction of each slot. This is referred to as a two-position U-segment sequential joining stator coil. In another example, one U-segment sequential joining stator coil can be configured using four conductor receiving positions adjacent to each slot in the circumferential direction. This is referred to as a 4-position U-shaped segment sequential joining stator coil. The 4-position type U-segment sequential joining stator coil includes a large segment in which a pair of legs are individually accommodated in a radially innermost conductor accommodating position and a radially outermost conductor accommodating position, and a second radial direction A small segment in which a pair of legs are individually accommodated in the conductor accommodating position and the third conductor accommodating position in the radial direction is used. In the head side coil end, the head end of the large segment is arranged to wrap the head end of the small segment.

  Each phase coil thus configured is connected in a star shape, for example, to complete a U-shaped segment sequential joining stator coil. Neutral and lead output leads for each phase coil (one-phase U-segment sequentially joined stator coil) by dividing the U-shaped head of the U-shaped segment at the appropriate location, or It can be composed of two I-shaped conductors.

  Two-position U-shaped segment sequential joining stator coil occupying two conductor accommodating positions in the slot by increasing the conductor accommodating position of the slot, or four-position U-shaped segment occupying four conductor accommodating positions in the slot It is obvious that a plurality of sequentially joined stator coils can be arranged in the radial direction. More specifically, in the two-position type U-shaped segment sequential joint stator coil, the two conductor receiving positions adjacent to each other in the slot are occupied by the slot conductor portion of the U-shaped conductor, and in the four-position type U-segment sequential joint stator coil The two conductor receiving positions adjacent to each other are occupied by the slot conductor portion of the U-shaped conductor. If the two-position U-shaped segment sequential joining stator coil or the four-position U-segment sequential joining stator coil is arranged to overlap in the radial direction, the motor output can be improved.

  Hereinafter, this method is referred to as a multiple coil radial stacking structure, and among these coils, a radially inner coil (that is, an inner U-segment sequential joining stator coil) is referred to as an inner coil, and a radially outer coil ( That is, the outer U-segment sequential joining stator coil) is abbreviated as an outer coil.

  In order to form the head skew portion in the above-described multi-coil radial overlapping structure, a method of simultaneously twisting the U-shaped conductor for the inner coil and the U-shaped conductor for the outer coil using a multiple rotation ring has been proposed. ing. Hereinafter, this method is referred to as a simultaneous twisting method or a simultaneous rotation method.

  In the multi-coil radial overlapping arrangement comprising the inner coil and the outer coil described above, the last (or first) slot conductor portion of the outer coil and the inner coil can be connected in series to the inner coil and the outer coil in phase. It is preferable that the inner coil and the outer coil are connected in series by using an inter-coil connecting wire having a first (or final) slot conductor portion and a specially shaped head portion connecting these two slot conductor portions. It is.

The above-described U-segment sequential joining stator coil and the manufacturing method thereof have already reached the level of well-known technology according to the following patent documents and the like described above, and thus further description of the prior art will be omitted. This U-shaped segment sequential joining stator coil clearly has a simpler winding structure than the traditional winding stator coil, so that the slot space factor can be improved and the coil end can be made more compact. The winding process can also be simplified.
Japanese Patent No. 3118837 Japanese Patent No. 3178468 Japanese Patent No. 3199068 JP 2000-139049 A JP 2000-350423 A JP 2001-045721 A JP 2001-069731 A JP 2001-245447 A JP 2002-218689 A JP 2003-189520 A JP 2004-032882 A JP 2004-032884 A JP 2004-032890 A JP 2004-032897 A JP 2004-048939 A JP 2004-089441 A JP 2004-048967 A JP 2004-064914 A JP 2004-166316 A JP 2005-6364 A JP 2005-211951 A

  However, in the above-described multi-coil radial overlapping arrangement composed of the inner coil and the outer coil, the connecting wires between the coils are the U-shaped conductor for the inner coil and the U-shaped conductor for the outer coil (hereinafter collectively referred to as a normal U-shaped conductor). Usually, it has a different circumferential expansion amount. That is, the final circumferential position (or first circumferential position) of the inner coil to which the inter-coil connecting wire is connected and the first circumferential position (or final circumferential position) of the outer coil are usually U-shaped conductors. Since it is completely different from the circumferential expansion amount (usually one magnetic pole pitch), the manufacture and assembly are not easy. In addition, since the tip of the head portion of the inter-coil crossing wire is shaped so as to cover the outer side in the axial direction than the tip of the head portion of the U-shaped conductor, the axial protrusion length of the head coil end is increased and the physique of the rotating electrical machine is increased. The problem of increased weight occurred.

  Further, when the crossover is obtained by connection as in Patent Document 5, there is a problem that an extra connection process is required.

  SUMMARY OF THE INVENTION The present invention has been made in view of the above problems, and provides a U-segment sequential joining stator coil manufacturing method capable of producing a U-segment sequential joining stator coil having a compact coil connecting wire in a simple process. Its purpose is to provide.

  A method of manufacturing a U-segment sequential joining stator coil according to the present invention that solves the above-described problems includes a U-shaped head tip portion and a head skew portion that is developed circumferentially from both ends of the head tip portion. An outer coil formed by sequentially connecting a number of deployed U-shaped conductors in series with each other, a U-shaped head tip portion, and a head skew portion developed in the circumferential direction from both ends of the head tip portion A large number of developed U-shaped conductors respectively connected in series are arranged in series, arranged inside the outer coil in the radial direction, a substantially U-shaped head tip, and a circumference from both ends of the head tip. A U-character having a coil-to-coil connecting wire which is constituted by a U-shaped conductor for a coil-to-coil connecting wire that has been developed and has a skewed head portion that is expanded in a direction and that connects the outer coil and the inner coil in series for each phase. In the method of manufacturing a conductor sequential joining stator coil, U U-shaped conductor for inner coil, U-shaped conductor for outer coil, and coil having an undeveloped U-shaped segment, each having a head-shaped head portion and a pair of straight portions extending in parallel from both ends of the head-tip portion A U-shaped conductor preparing step for preparing a U-shaped conductor for a jumper wire, and processing the tip of the head portion of the U-shaped conductor for a jumper wire between the coils between a pair of straight portions of the U-shaped conductor for the jumper wire A pre-deployment step in which the distance is a predetermined pre-circumferential deployment amount, and a pair of straight portions of the outer coil U-shaped conductor are individually held by a plurality of outer rings, and a pair of straight lines of the inner coil U-shaped conductor The outer ring and the inner side that are coaxial with each other in a state where the pair of linear portions of the U-shaped conductor for the inter-coil connecting wire are individually held by the outer ring and the inner ring. By relative rotation of the ring, Side coil U-conductors, is characterized by sequentially performing the present deployment forming the head slant part in a U-conductors and U-shaped conductor coils between crossover wire for the inner coil.

  That is, according to the present invention, a pair of the U-shaped conductors for inter-coil connecting wires is obtained by performing a process in advance to give a predetermined amount of development in the preliminary circumferential direction to the head end portion of the U-shaped conductor for inter-coil connecting wires. The straight line portion is separated in the circumferential direction by the amount of the preliminarily developed circumferential direction, and the preliminarily developed U-conductor for the inter-coil connecting wire together with the other normal U-shaped conductors is referred to as an inner ring and an outer ring (hereinafter referred to as a multiple rotation ring). The head head skew portion is formed in a portion adjacent to the head tip portion among the straight portions. Thus, the circumferential distance between the pair of slot conductor portions of the inter-coil connecting wire is the sum of the preliminary circumferential development amount given by the preliminary development step and the main circumferential development amount given by the main development step.

  In other words, according to the present invention, the circumferential development amount obtained by subtracting the circumferential development amount provided by the regular development step performed together with the normal U-shaped conductor out of the circumferential development amount of the U-shaped conductor for the inter-coil connecting wire is previously coiled. The processing applied to the tip of the head portion of the U-shaped conductor for the jumper wire is performed.

  If it does in this way, a pair of head skew parts of the U-shaped conductor for connecting wires between coils can be easily inserted between the head skew parts of the normal U-shaped conductor. In addition, since the pair of head skew portions of the U-shaped conductor for the connecting wire between the coils is developed (twisted) in the circumferential direction by the same amount by the same process as the head skew portion of the U-shaped conductor, The parallelism between the head skew portion of the U-shaped conductor for the jumper wire and the head skew portion of the normal U-shaped conductor adjacent to the circumferential direction in the circumferential direction can be ensured satisfactorily.

  In addition, the preliminary circumferential direction expansion amount given to the U-shaped conductor for the inter-coil connecting wire in the pre-deployment step can be given only by the circumferential extending distance of the head end portion of the U-shaped conductor for the inter-coil connecting wire. In addition to this, even if bending is performed to tilt both ends of the tip of the head in the circumferential direction, the development amount in the preliminary circumferential direction may be set as a necessary amount. Further, this preliminary unfolding step may be performed before the unfolding step by using the rotating ring used in the unfolding step, and the undeployed coil crossing without using the unfolding ring used in the unfolding step. You may carry out by bending the U-shaped conductor for wires.

  In a preferred aspect, the preliminary deployment step includes holding the pair of straight portions of the undeveloped U-conductor for the connecting wire between the coils individually on the outer ring and the inner ring, and then rotating the outer ring and the inner ring. By moving it, a predetermined amount of development in the preliminary circumferential direction is given to the head end portion or straight portion of the U-shaped conductor for connecting wires between coils.

  That is, according to this aspect, the preliminary expansion process is performed before the main expansion process using the multiple rotation ring used in the main expansion process. If it does in this way, the circumferential direction expansion | deployment operation | work of the U-shaped conductor for connecting wires between coils can be simplified.

  In addition, when the head end portion or the straight portion of the U-shaped conductor for the inter-coil connecting wire is expanded (twisted) by a predetermined preliminary circumferential direction development amount using the multiple rotation ring, the effect of this twist is caused by this expansion process. There is a possibility of adversely affecting the straight line portion (extending in the axial direction) as the head skew portion of the U-shaped conductor for the inter-coil connecting wire to be twisted. In order to avoid this problem, when the U-shaped conductor for the inter-coil connecting wire is preliminarily developed, the head skew portion is also inserted into the hole (or groove) of the multiple rotating ring, The straight line portion as the planned skew portion of the character conductor may not be developed in the circumferential direction. In this case, after the preliminary deployment process is completed, the pre-scheduled portion of the head portion of the U-shaped conductor for the inter-coil connecting wire is pulled out from the hole (or groove) of the multiple rotation ring, and this head in the next main deployment process. What is necessary is just to develop the part skew part planned part to the circumferential direction, and to make a head skew part.

  In a preferred aspect, the connecting wire between the coils is located between the inner coil and the outer coil and extends in the circumferential direction, and extends radially from both sides of the circumferential extension portion. A pair of radially extending portions extending in the circumferential direction by a predetermined circumferential expansion amount, and the preliminary deployment step includes a pair of radially extending portions of the inter-coil connecting wires or The predetermined circumferential development amount is given to the pair of linear portions.

  That is, according to this aspect, the head end portion of the U-shaped conductor for the inter-coil connecting wire has a circumferentially extending portion extending in the circumferential direction between the inner coil and the outer coil, and this circumferentially extending portion. It consists of a pair of radial direction extension part extended in a substantially radial direction reverse direction from the part. In this embodiment, the pair of radially extending portions or the pair of linear portions are preliminarily developed in the circumferential direction by a predetermined amount. If it does in this way, in addition to the circumferential direction deployment amount performed in this deployment process among the circumferential direction deployment amount required for the head tip part or the straight part of the U-shaped conductor for the connecting wire between coils, The straight portion can be further twisted (deployed in the circumferential direction). Preferably, the radially extending portion of the head tip of the U-shaped conductor for inter-coil connecting wires has an inclination substantially equal to the circumferential inclination of the head tip of the normal U-shaped conductor adjacent in the circumferential direction. It is suitable to have. Accordingly, an appropriate gap is provided between the radially extending portion of the head tip portion of the U-shaped conductor for the crossover coil between the coils and the head tip portion of the normal U-shaped conductor adjacent to the circumferential direction. Can be secured.

  In a preferred aspect, the U-shaped conductor preparing step includes preparing a plurality of U-shaped conductors for connecting between the coils to connect the inner coil and the outer coil, and the preliminary deploying step includes a step between the plurality of coils. After a part of the U-shaped conductor for connecting wires is preliminarily developed, the remaining part is developed by the additional preliminary development process or the main development process.

  That is, according to this aspect, the head skew portion of the plurality of U-shaped conductors for connecting wires between the coils having different circumferential development amounts is combined with the normal U-shaped conductor by the present unfolding step. At the time of forming, different preliminary circumferential direction expansion amounts are given to the U-shaped conductors for connecting wires between the coils by the preliminary expansion process. For example, when considering two U-conductors for connecting wires between coils, first, a predetermined first preliminary circumferential development amount is given to the first U-conductor for connecting wires between coils by a multiple rotation ring, and then multiple By rotating the multiple rotation ring by additionally setting a second U-conductor for the connecting wire between the coils to the rotating ring, the second spare U-conductor for the connecting wire between the first and second coils is rotated. Gives the amount of circumferential expansion. As a result, the U-conductor for the first inter-coil crossover wire is given a total amount of development in the preliminary circumferential direction of the first preliminary circumferential direction development amount and the second preliminary circumferential direction development amount, and the second coil Only the second preliminarily circumferential expansion amount is given to the U-shaped conductor for the crossover line.

  More specifically, by simultaneously deploying a plurality of types of undeveloped U-shaped conductors for undeveloped crossovers having different circumferentially developed amounts, their curvature radii can be easily equalized.

  Further, by adjusting the length of the straight portion of the undeveloped crossover U-shaped conductor, a plurality of types of undeveloped crossover U-shaped conductors having different unfolded amounts in the circumferential direction are given the same bending portion curvature radius. It can be manufactured easily. For example, when bending multiple types of undeveloped crossover U-shaped conductors with different circumferential development amounts by the press molding method, many bending molds and jigs are required, and more are required to replace them. The number of man-hours is required. These problems can be improved by adjusting the length of the straight portion of the U-shaped conductor for undeveloped crossover lines described above, in other words, by adjusting the length of the straight portion to be skewed during circumferential development. Solved. Incidentally, the adjustment itself of the length of the straight portion to be skewed of the undeveloped crossover U-shaped conductor at the time of development in the circumferential direction adjusts the amount of insertion of the undeveloped crossover U-shaped conductor into the multiple rotation ring. This can be easily realized by using a feed amount adjusting device with a numerically controlled servo motor device.

  In addition, the circumferential direction expansion amount of the U-shaped conductor for the connecting wire between the coils referred to here is the head slanting of the U-shaped conductor for the connecting wire between the coils, which is equal to the circumferential amount of the normal extending portion of the head portion of the U-shaped conductor Note that this is the amount obtained by subtracting the circumferential expansion amount of the row portion. However, when the total circumferential expansion amount of the second inter-coil connecting wire U-shaped conductor is equal to the circumferential expansion amount of the normal U-shaped conductor, the second inter-coil connecting wire U-shaped conductor is normally Similar to the U-shaped conductor, the circumferential expansion amount can be given only by the main expansion process. Furthermore, the circumferential direction expansion amount of the head end portion of the U-shaped conductor for the first and second inter-coil connecting wires is the length of the bending process and the circumferential extension portion without using the multiple rotation ring for this expansion process. It may be given only by adjustment.

  In a preferred aspect, among the plurality of inter-coil connecting wires, the inter-coil connecting wire having a longer radial distance is arranged on the outer side in the axial direction than the inter-coil connecting wire having a shorter radial distance. Thereby, for example, it is possible to satisfactorily prevent interference between a plurality of inter-coil connecting wires that cross in the axial direction.

  An embodiment in which the U-shaped segment sequential joining stator coil of the present invention is employed as a stator coil of an automotive alternator will be described with reference to the drawings. However, the present invention should not be construed as being limited to the following embodiments, and it is natural that the technical idea of the present invention may be implemented using other known techniques.

(Description of overall structure)
A sectional view in the axial direction of this vehicle alternator is shown in FIG. However, the stator coil 12 is schematically shown in FIG. The AC generator includes a stator 10 that functions as an armature, a rotor 50 that functions as a field element, a front housing 61 and a rear housing 62, and a rectifier 65 that converts AC power into DC power. The rotor 50 rotates integrally with the shaft 51 and includes a Landel pole core 52, a field coil 53, a slip ring 54, a mixed flow fan 56, and a centrifugal fan 57. The Landel-type pole core 52 is configured by combining a pair of pole cores 52a and 52b. The shaft 51 is driven to rotate by a vehicle engine through a pulley 58. The front housing 61 and the rear housing 62 support the rotor 50 and sandwich the stator 10.

  The stator 10 includes a stator core 11 and a stator coil 12 wound around the stator core 11. The stator coil 12 is a known U-segment sequential joining stator coil configured by sequentially connecting a large number of U-shaped conductors. Reference numeral 13 denotes a head-side coil end that protrudes rearward from the stator core 11 of the stator coil 12, and reference numeral 14 denotes an end-side coil end that protrudes frontward from the stator core 11 of the stator coil 12. Therefore, each U-shaped conductor constituting the U-segment sequential joining stator coil is inserted into each slot of the stator core 11 from the rear side to the front side. The leading end of each U-shaped conductor is sequentially connected for each phase to form three phase coils, and each phase coil is three-phase star-shaped to constitute the stator coil 12.

  In the embodiment shown in FIG. 1, the pair of leg portions of each U-shaped conductor is individually accommodated in a pair of slots separated by one magnetic pole pitch. In FIG. 1, the slot has eight conductor receiving positions in the radial direction, and the inner coil U-shaped conductor is inserted into the first to fourth conductor receiving positions from the radially inner side, and the fifth to eighth positions from the radially inner side. The outer coil U-shaped conductor is inserted through the conductor receiving position. The U-shaped conductors for the inner coils are sequentially connected on the end side to constitute an inner coil, and the U-shaped conductors for the outer coil are sequentially connected on the end side to constitute an outer coil. The inner coil and the outer coil are each composed of a three-phase coil, and the phase coils of the same phase of the inner coil and the outer coil are directly connected by an inter-coil connecting wire described later. In this embodiment, the remaining ends of each phase coil of the inner coil are connected to each other to form a neutral point, and the remaining ends of each phase coil of the outer coil constitute an external lead wire for each phase. Yes.

(Description of head side coil end)
The head-side coil end 13 is configured by a U-shaped head of each U-shaped conductor. The U-shaped head is a pair of U-shaped head tips and a semi-magnetic pole pitch extending (skewed) in the circumferential direction while approaching the axial slots from both ends of the head tips. It consists of a head skew part. One head skew part and the other head skew part of the same U-shaped head are arranged to be shifted by one conductor accommodating position pitch in the radial direction, and the U-shaped head tip is substantially in the radial direction. The pair of head end portions are connected to each other.

  Note that the end-side coil end 14 is formed by a protruding end portion of each U-shaped conductor. The projecting end portion extends from the slot and then extends away from the axial slot, and extends in the circumferential direction by a substantially semi-magnetic pole pitch (slopes), and a pair of end skew portions, It consists of an end portion protruding in the axial direction from the end of the skew portion. A pair of end tip portions adjacent to each other in the radial direction of the inner coil U-shaped conductor are welded, and a pair of end tip portions adjacent to each other in the radial direction of the outer coil U-shaped conductor are welded.

  In this embodiment, the inner coil and the outer coil are composed of the four-position U-shaped segment sequential joining stator coil composed of the U-shaped conductors that occupy the four conductor receiving positions that are adjacent to each other in the radial direction. The structure is essentially the same. The U-shaped conductor for the inner coil used for the inner coil will be described with reference to FIG. The shape and structure of the outer coil U-shaped conductor used for the outer coil are also the same as those shown in FIG.

  In FIG. 2, the large segment 17, which is a U-shaped conductor having a large head curvature radius, is inserted into the first and fourth conductor accommodation positions among the four conductor accommodation positions continuous in the radial direction of each slot. A small segment 27 that is a U-shaped conductor having a small head curvature radius is inserted through the conductor receiving position. A pair of slot insertion portions of the large segment 17 are referred to as slot conductor portions 18a and 18b. A pair of slot insertion portions of the small segment 27 are referred to as slot conductor portions 28a and 28b. 19 is a U-shaped head of the large segment 17, and 29 is a U-shaped head of the small segment 27. The large segment 17 has a pair of protruding end portions 21a and 21b, and the protruding end portions 21a and 21b have end oblique portions 22a and 22b and end end portions 23a and 23b. Similarly, the small segment 27 has a pair of protruding end portions 31a and 31b, and the protruding end portions 31a and 31b have end oblique portions 32a and 32b and end tip portions 33a and 33b. The end tip portions 23b and 33b are welded to become a welded portion 41a, and the end tip portions 23a and 33a are welded to become a welded portion 41b. As a result, it can be seen that the 4-position U-segment sequential joining stator coil is composed of the small segment 27 and the large segment 17 surrounding the small segment 27.

  The shape of the head side coil end 13 of the stator coil 12 using the pair of the large segment 17 and the small segment 27 is shown in FIG. Reference numeral 100 denotes an inner coil, and reference numeral 200 denotes an outer coil. In FIG. 3, 17 a is the head tip of the large segment 17 that is a large U-shaped conductor, 27 a is the head tip of the small segment 27 that is a small U-shaped conductor, and 17 b is the radially inner side of the large segment 17. A head skew portion, 17c is a head skew portion on the radially outer side of the large segment 17, 27b is a head skew portion on the radially inner side of the small segment 27, and 27c is a head portion on the radially outer side of the small segment 27. An oblique portion, 17d is a slot conductor portion inside the large segment 17, 17e is a slot conductor portion outside the large segment 17, 27d is a slot conductor portion inside the small segment 27, and 27e is a slot conductor portion outside the small segment 27. Part.

  The slot of the stator core 11 has eight conductor housing positions C1 to C8 in the radial direction. The conductor housing positions C1 to C4 accommodate the slot conductor portions 17d, 27d, 27e, and 17e of the large segment 17 and the small segment 27 that constitute the inner coil 100. The conductor housing positions C5 to C8 accommodate the slot conductor portions 17d, 27d, 27e, and 17e of the large segment 17 and the small segment 27 that constitute the outer coil 200.

  The standard structure and manufacturing method of the above-described four-position U-segment sequential joining stator coil is described in detail in each of the above-mentioned patent documents such as Patent Document 20 and the like and is no longer known. Description is omitted. However, it goes without saying that the present invention can be applied to, for example, a two-position U-shaped segment sequential joining stator coil in addition to the above-described four-position U-shaped segment sequential joining stator coil.

(Arrangement example 1 of the connecting wire between coils)
The arrangement example 1 of the connecting wire between coils will be described in more detail with reference to FIGS. FIG. 3 is a side view of the vicinity of the head-side coil end 13, and FIG. 4 is a circumferential partial development view showing a state where the vicinity of the inter-coil connecting wire 300 of the head-side coil end 13 is developed in the circumferential direction.

  In FIG. 3, reference numeral 300 denotes an inter-coil connecting wire for connecting the inner coil 100 and the outer coil 200 in series for each phase. The inter-coil connecting wire 300 is an inter-coil connecting wire that connects one end of the inner coil and one end of the outer coil 200. The inter-coil connecting wire 300 includes an inner slot conductor portion 301 accommodated in a conductor accommodating position C1 of a predetermined slot, an outer slot conductor portion 302 accommodated in a conductor accommodating position C8 of a predetermined slot, and a slot conductor portion. 301, an inner skew crossing portion (head skewing portion of the inter-coil connecting wire referred to in the present invention) 303 that extends from 301 and is obliquely provided in the same circumferential direction as the head skew portion 17b of the inner coil 100; The outer diagonally extending portion extending from the slot conductor portion 302 and obliquely inclined in the same direction as the head inclined portion 17c of the outer coil 200 (head skew of the inter-coil connecting wire referred to in the present invention) Part) 304 and a head crossover part (head end part of the inter-coil crossover line referred to in the present invention) 305 linking the two oblique crossover parts 303 and 304. The slot conductor part 301 constitutes the first (or last) slot conductor part of the inner coil 100, and the slot conductor part 302 constitutes the last (or first) slot conductor part of the outer coil 200.

  In this embodiment, as shown in FIGS. 3 and 4, the head crossover portion 305 is disposed at a position that does not protrude outward in the axial direction from the head tip portion 17 a of the large segment 17 of the inner coil 100 and the outer coil 200. Has been. For this reason, the axial direction length of the head side coil end 13 can be shortened.

  Further, in this embodiment, the skew crossing portion 303 on the inner side of the inter-coil connecting wire 300 is obliquely installed in the same direction as that of the innermost head skew portion 17b in the radial direction of the inner coil 100 at the same radial direction. In addition, an oblique crossing portion 304 on the outer side of the inter-coil connecting wire 300 is obliquely provided in the same direction as the outermost head oblique portion 17c in the radial direction of the outer coil 200 at the same position in the radial direction. In other words, the inner skew crossing portion 303 that is connected to the inner end in the radial direction of the head crossover portion 305 of the inter-coil connecting wire 300 and skews in the circumferential direction and the axial direction is the head skew inside each large segment 17. Since one of the parts 17b is spatially arranged at the innermost side of the inner coil 100 at a position that should be occupied, the continuity and direction change from the inner skew transition part 303 to the head transition part 305 are different from each other. It is not obstructed by each part of the segment 17. Similarly, the outer oblique transition portion 304 that is connected to the radially outer end of the head transition portion 305 of the inter-coil connecting wire 300 and obliquely travels in the circumferential direction and the axial direction is also applied to the outer oblique portion of each large segment 17. Since the row portion 17c is spatially arranged on the outermost side of the outer coil 200 at a position to be occupied, the continuity and direction change from the outer oblique crossover portion 304 to the head crossover portion 305 are another large segment. 17 parts are not disturbed. That is, the inter-coil connecting wire 300 can be arranged in a compact manner while suppressing spatial interference with other U-shaped conductors.

  FIG. 5 shows a state in which the vicinity of the inter-coil connecting wire 300 of the head side coil end 13 is viewed from the rear in the axial direction. The head crossover portion (head tip portion) 305 includes a circumferential crossover portion (circumferential extension portion referred to in the present invention) 3051 described later and an inner radial crossover portion (radial extension portion referred to in the present invention). 3052 and an outer radial crossing portion (radial extending portion referred to in the present invention) 3053. The circumferential crossover portion 3051 is accommodated in the inter-coil recess portion x located between the head tip portion 17a of the inner coil 100 and the head tip portion 17a of the outer coil 200 and extending in the circumferential direction. Extend to.

  The inner radial crossing portion 3052 is accommodated in the inter-segment gap y between one end of the circumferential crossing portion 3051 and the head tip portion 17a of the large segment 17 of the inner coil 100 and extends substantially inward in the radial direction. Yes. That is, the inner radial crossing portion 3052 extends substantially in the radial direction in the same manner as the other head tip portion 17a at a position that one of the head tip portions 17a of each large segment 17 of the inner coil 100 should occupy. ing.

  The outer radial crossover portion 3053 is accommodated in the inter-segment gap z between the other end of the circumferential crossover portion 3051 and the head tip portion 17a of the large segment 17 of the outer coil 200 and extends substantially outward in the radial direction. ing. That is, the outer radial crossing portion 3053 extends substantially in the radial direction in the same manner as the other head tip portion 17a at a position that one of the head tip portions 17a of each large segment 17 of the outer coil 200 should occupy. ing.

  In FIG. 5, for easy understanding, the inter-segment gaps y and z between the head end portions 17 a of the two large segments 17 adjacent to each other are shown large. , Z can be further reduced.

  By forming the head crossover portion 305 of the coil crossover wire 300 in a substantially crank shape as shown in FIG. 5, the head crossover portion 305 of the coil crossover wire 300 can be arranged in a compact manner, and the head side coil end 13 axial protrusion lengths can be reduced. Further, by adjusting the length and position of the circumferential crossover portion 3051 of the head crossover portion 305, the start (or end) position for each phase of the inner coil 100 to be connected to the outer coil 200 for each phase is appropriately set. You can choose. Similarly, the end (or start) position for each phase of the outer coil 200 to be connected to the inner coil 100 for each phase can be appropriately selected.

(Arrangement example 2 of the connecting wire between coils)
Other arrangement examples of the inter-coil connecting wire 300 will be described in detail below with reference to FIGS. The inter-coil connecting wire 300 is disposed between the conductor housing positions C2 and C7. FIG. 6 is a side view of the vicinity of the head-side coil end 13, and FIG. 7 is a circumferential partial development view showing a state in which the vicinity of the inter-coil connecting wire 300 of the head-side coil end 13 is developed in the circumferential direction.

  In FIG. 6, the inter-coil connecting wire 300 extends from the inner slot conductor portion 301 accommodated in the conductor accommodating position C <b> 2, the outer slot conductor portion 302 accommodated in the conductor accommodating position C <b> 7, and the slot conductor portion 301. An inner skew crossing portion 303 obliquely provided in the same direction as the head skew portion 27b of the inner coil 100, and a head skew portion 27c of the outer coil 200 extending from the slot conductor portion 302. And an outer oblique transition portion 304 that is obliquely arranged in the same direction in the circumferential direction, and a head transition portion 305 that connects the two oblique transition portions 303 and 304. The slot conductor part 301 constitutes the first (or last) slot conductor part of the inner coil 100, and the slot conductor part 302 constitutes the last (or first) slot conductor part of the outer coil 200.

  In this embodiment, as shown in FIGS. 6 and 7, the head crossover portion 305 is disposed at a position that does not protrude outward in the axial direction from the head tip portion 17 a of the large segment 17 of the inner coil 100 and the outer coil 200. Has been. For this reason, the axial direction length of the head side coil end 13 can be shortened.

  Further, in this embodiment, an oblique crossing portion 303 inside the inter-coil connecting wire 300 is obliquely installed in the same direction as the head oblique portion 27b of the inner coil 100 in the radial direction, and further, between the coils. A skew crossing portion 304 outside the connecting wire 300 is obliquely provided in the same direction as the head skew portion 27c of the outer coil 200 at the same radial position. That is, the inner skew crossing portion 303 that is connected to the inner end in the radial direction of the head crossover portion 305 of the inter-coil connecting wire 300 and skews in the circumferential direction and the axial direction is the head skew inside each small segment 27. Since one of the portions 27b is spatially disposed at a position to be occupied, the continuity and direction change from the inner skew crossing portion 303 to the head crossing portion 305 are obstructed by the other small segments 27. There is nothing to do. Similarly, the outer oblique transition portion 304 that is connected to the radially outer end of the head transition portion 305 of the inter-coil connecting wire 300 and obliquely travels in the circumferential direction and the axial direction is also applied to the outer head oblique portion of each small segment 27. Since the row portion 27c is spatially arranged at a position to be occupied, the continuity and direction change from the outer oblique crossover portion 304 to the head crossover portion 305 are obstructed by other portions of the small segment 27. There is nothing. That is, the inter-coil connecting wire 300 can be arranged in a compact manner while suppressing spatial interference with other U-shaped conductors.

  FIG. 8 shows a state in which the vicinity of the inter-coil connecting wire 300 of the head side coil end 13 is viewed from the rear in the axial direction. The head crossover portion 305 includes a circumferential crossover portion 3051 described later, an inner radial crossover portion 3052, and an outer radial crossover portion 3053. The circumferential crossover portion 3051 is accommodated in the inter-coil recess portion x located between the head tip portion 17a of the inner coil 100 and the head tip portion 17a of the outer coil 200 and extending in the circumferential direction. Extend to.

  The inner radial crossing portion 3052 is accommodated in the inter-segment gap y between one end of the circumferential crossing portion 3051 and the head tip portion 17a of the large segment 17 of the inner coil 100 and extends substantially inward in the radial direction. Yes. However, in the second embodiment, unlike in the first embodiment, the inner radial crossing portion 3052 is located at the position where one of the head tip portions 17a of the large segments 17 of the inner coil 100 should occupy the other head. Like the tip portion 17a, it does not extend in the substantially radial direction. Instead, in the second embodiment, the inner radial crossing portion 3052 is the same as the other head tip portion 27a at a position that one of the head tip portions 27a of each small segment 27 of the inner coil 100 should occupy. Extends substantially in the radial direction.

  The outer radial crossover portion 3053 is accommodated in the inter-segment gap z between the other end of the circumferential crossover portion 3051 and the head tip portion 17a of the large segment 17 of the outer coil 200 and extends substantially outward in the radial direction. ing. However, in the second embodiment, unlike in the first embodiment, the outer radial crossing portion 3053 is located at the position where one of the head tip portions 17a of the large segments 17 of the outer coil 200 should occupy the other head. Like the tip portion 17a, it does not extend in the substantially radial direction. Instead, in the second embodiment, the outer radial crossing portion 3053 is the same as the other head tip portion 27a at a position that one of the head tip portions 27a of the small segments 27 of the outer coil 200 should occupy. Extending substantially in the radial direction. Therefore, the inter-coil connecting wire 300 according to the second embodiment needs to secure inter-segment gaps y and z between the two head tip portions 17a and 17a of the large segment 17 adjacent to each other in the circumferential direction. In this embodiment, the gap between the radial crossover portions 3052 and 3053 of the inter-coil connecting wire 300 and the head end portion 17a of the large segment 17 is smaller than that in the first embodiment. In other respects, the inter-coil connecting wire 300 of the second embodiment can achieve the same effects as the inter-coil connecting wire 300 described in the first embodiment.

(Example 3 of arrangement of connecting wire between coils)
Other arrangement examples of the inter-coil connecting wire 300 are shown in FIGS. However, it should be noted that the conductor accommodation position arrangement order in FIG. 11 is opposite to that in FIGS. 3 and 6. The slot conductor portion of the inter-coil connecting wire 300 is disposed between the conductor housing positions C2 and C6. FIG. 9 is a side view of the vicinity of the head-side coil end 13, and FIG. 10 is a circumferential partial development view showing a state in which the vicinity of the inter-coil connecting wire 300 of the head-side coil end 13 is developed in the circumferential direction. 11 is a front view of the head side coil end 13 viewed from the axial rear side.

  In FIG. 9, the inter-coil connecting wire 300 extends from the inner slot conductor portion 301 accommodated in the conductor accommodating position C <b> 2, the outer slot conductor portion 302 accommodated in the conductor accommodating position C <b> 6, and the slot conductor portion 301. An inner oblique crossing portion 303 obliquely provided in the same circumferential direction as the head oblique portion 27b of the small segment 27 of the inner coil 100, and a small segment of the outer coil 200 extending from the slot conductor portion 302. 27 of the head skew portion 27b and the outer skew transition portion 304 obliquely arranged in the same circumferential direction, and the head transition portion 305 connecting the two skew transition portions 303 and 304. The slot conductor part 301 constitutes the first (or last) slot conductor part of the inner coil 100, and the slot conductor part 302 constitutes the last (or first) slot conductor part of the outer coil 200.

  In this arrangement example, as shown in FIGS. 9 and 10, the head crossover portion 305 protrudes outward in the axial direction from the head tip portion 17 a of the large segment 17 of the inner coil 100 and the outer coil 200. Therefore, it is disadvantageous in terms of shortening the axial length of the head-side coil end 13. However, the skew crossing portion 303 inside the inter-coil connecting wire 300 is obliquely installed in the same direction as the head skew portion 27b of the small segment 27 of the inner coil 100 at the same position in the radial direction. The oblique crossover portion 304 outside the connecting wire 300 is obliquely provided in the same direction as the head oblique portion 27b of the small segment 27 of the outer coil 200 at the same position in the radial direction. That is, the inner skew crossing portion 303 that is connected to the radially inner end of the head crossover portion 305 of the inter-coil connecting wire 300 and skews in the circumferential direction and the axial direction is the head skewing portion 27b of each small segment 27. Is located in a position to be occupied by one of the two, the continuity and direction change from the inner skew crossing part 303 to the head crossing part 305 are disturbed by each part of the other small segment 27. There is no. Similarly, the outer skew crossing portion 304 that is connected to the radially outer end of the head crossover portion 305 of the inter-coil connecting wire 300 and skews in the circumferential direction and the axial direction is also the head skew portion of each small segment 27. 27b is spatially arranged at a position to be occupied, and the continuity and direction change from the outer oblique crossing part 304 to the head crossing part 305 are obstructed by other parts of the small segment 27. No.

  FIG. 11 shows a state where the vicinity of the inter-coil connecting wire 300 of the head-side coil end 13 is viewed from the rear in the axial direction. The head crossover portion 305 includes a circumferential crossover portion 3051 described later, an inner radial crossover portion 3052, and an outer radial crossover portion 3053. The circumferential crossover portion 3051 is accommodated in the inter-coil recess portion x located between the head tip portion 17a of the inner coil 100 and the head tip portion 17a of the outer coil 200 and extending in the circumferential direction. Extend to.

  The inner radial crossing portion 3052 is accommodated in the inter-segment gap y between one end of the circumferential crossing portion 3051 and the head tip portion 17a of the large segment 17 of the inner coil 100 and extends substantially inward in the radial direction. Yes. However, in this embodiment, unlike Embodiment 1, the inner radial crossover portion 3052 is located at the position where one of the head tip portions 17a of each large segment 17 of the inner coil 100 should occupy the other head tip. Like the portion 17a, it does not extend in the substantially radial direction. Instead, in this embodiment, the inner radial crossing portion 3052 is similar to the other head tip portions 27a at a position that one of the head tip portions 27a of each small segment 27 of the inner coil 100 should occupy. It extends in a substantially radial direction.

  The outer radial crossover portion 3053 is accommodated in the inter-segment gap z between the other end of the circumferential crossover portion 3051 and the head tip portion 17a of the large segment 17 of the outer coil 200 as shown in FIG. After being bent so as to cover the outer side in the axial direction of the head tip portion 17a of the large segment 17, it is bent into the inter-segment gap z. For this reason, the axial length of the head-side coil end 13 described above increases. Further, the inter-coil connecting wire 300 according to the third embodiment needs to sufficiently secure the inter-segment gaps y and z between the two head tip portions 17a and 17a of the large segment 17 adjacent to each other in the circumferential direction. is there. In this comparative example, the gap between the radial crossover portions 3052 and 3053 of the inter-coil connecting wire 300 and the head end portion 17a of the large segment 17 is smaller than that in the first embodiment. 5, 8, and 11, the black colored region is a flat side surface that forms the rear end surface of the head crossover portion 305 of the inter-coil connecting wire 300.

(Description of manufacturing method of inter-coil connecting wire 300)
Hereinafter, the production of the inter-coil connecting wire 300 will be described below. First, the multiple rotation ring 400 used for the circumferential development of the inter-coil connecting wire 300 and the normal U-shaped conductor will be described.

(Explanation of multiple rotation ring)
A multiple rotation ring 400 constituted by a quadruple ring used in this embodiment will be described with reference to FIG. The multiple rotation ring 400 is a device for developing (twisting) a U-shaped conductor or a U-shaped conductor for connecting wires between coils in the circumferential direction. However, the multiple rotation ring that can be used in the practice of the present invention is not limited to the quadruple multiple rotation ring 400 shown in FIG. 12, and may be an eight-fold ring configuration or a triple-ring configuration. Alternatively, other numbers of ring configurations may be used.

  In the quadruple ring configuration shown in FIG. 12, the ring 401 that holds the straight portions of the U-shaped conductors at the conductor receiving positions C1 and C2 of each slot, and the straight portions of the U-shaped conductors at the conductor receiving positions C3 and C4 of each slot. A ring 402 for holding, a ring 403 for holding the straight portion of the U-shaped conductor at the conductor receiving positions C5 and C6 of each slot, and a ring 404 for holding the straight portion of the U-shaped conductor at the conductor receiving positions C7 and C8 of each slot. Are coaxially arranged so as to be relatively rotatable. It is assumed that the rings 401 and 403 rotate clockwise and the rings 402 and 404 rotate counterclockwise during simultaneous rotation.

  In the eight-ring configuration, eight rings arranged coaxially so as to be capable of relative rotation are individually arranged for each of the conductor receiving positions C1 to C8. In the triple ring configuration, a ring that holds the straight portion of the U-shaped conductor at the conductor receiving positions C1 and C2 of each slot, and a ring that holds the straight portion of the U-shaped conductor at the conductor receiving positions C3 to C6 of each slot; A ring that holds the straight portion of the U-shaped conductor at the conductor receiving positions C7 and C8 of each slot is coaxially arranged so as to be relatively rotatable. In any configuration, each ring has a hole for holding the straight portion of the U-shaped conductor at a slot pitch in the circumferential direction.

  Next, FIG. 13 schematically illustrates an example of the connection between the coils, and another example is schematically illustrated in FIG. FIG. 13 shows an example in which long conductor pieces are sequentially bent to produce a tall undeveloped inter-coil connecting wire, and finally completed together with a normal U-shaped conductor by simultaneous development (main development). FIG. 14 shows that after a long conductor piece is first bent into a pine needle shape, the head crossover portion 305 and the skew crossover portions 303 and 304 are bent and subjected to necessary preliminary development (described later), and finally the normal An example of completion with a U-shaped conductor by simultaneous development (main development) is shown.

(Embodiment 1)
A preferred embodiment of the method for developing the circumferential direction of the inter-coil connecting wire 300 in the arrangement example 1 described above will be described below.

  In the arrangement example 1 of the inter-coil connecting wire 300 shown in FIGS. 3 to 5, a straight line of the inter-coil connecting wire 300 in which the head connecting portion (head end portion) 305 is bent in advance in a crank shape as shown in FIG. 5. The unfolded straight portion of the inner coil U-shaped conductor and the unfolded straight portion of the outer coil U-shaped conductor are set in each hole of the multiple rotation ring 400. At this time, of the straight portions of the U-shaped conductors, the portions that become the head skew portion and the skew crossing portion are put out from the holes of the rings 401 to 404.

  Next, the front end portions of the undeveloped inner coil U-shaped conductor and outer coil U-shaped conductor are held by a holder (not shown) so that they cannot be bent in the circumferential direction. The 305 radial crossover portions (radially extending portions) 3052 and 3053 are held by a holder (not shown) so that they cannot be bent in the circumferential direction. Note that the holder may be slightly rotated.

  Next, each of the rings 401 to 404 is rotated by a half magnetic pole pitch (main development process). As a result, head oblique portions 17b, 17c, 27b, 27c are formed on the small segment 27 and the large segment 17 which are U-shaped conductors for the inner coil, and the small segment 27 which is also the U-shaped conductor for the outer coils. Head skew parts 17b, 17c, 27b and 27c are formed on the large segment 17, and skew bridge parts 303 and 304 are formed on the inter-coil connecting wire 300. The head skew part and the skew bridge part are It becomes almost parallel. Note that, in the simultaneous rotation of the rings 401 to 404 in the main development process, it is preferable that the head crossing portion 305 is pressed against the rings 401 to 404 by a pressing plate (not shown).

  In the circumferential deployment method of the inter-coil connecting wire 300 according to the arrangement example 1, the circumferential pitch between the pair of slot conductor portions of the inter-coil connecting wire 300 is set to the circumference of the oblique connecting portions 303 and 304 of the inter-coil connecting wire 300. It is equal to the sum of the direction expansion amount and the sum of the circumferential direction expansion amount of the head crossover portion 305 of the inter-coil connecting wire 300. Therefore, the circumferential pitch required for the inter-coil connecting wire 300 can be obtained by adjusting the circumferential expansion amount of the head connecting portion 305 of the inter-coil connecting wire 300. In addition, although the circumferential direction expansion amount of the head transition part 305 of the crossover coil 300 is substantially equal to the length of the circumferential transition part (circumferential extension part) 3051 of the head transition part 305, the head transition part When the 305 radial crossover portions (radial extension portions) 3052 and 3053 are inclined in the circumferential direction, the length of the circumferential crossover portion 3051 is set including this.

  In other words, in this arrangement example 1, the head transition portion 305 formed in a crank shape having the above-mentioned circumferential length is bent on the undeveloped inter-coil connection wire 300 in which the skew transition portions 303 and 304 are not yet formed. (Preliminary development process). Thereby, the head side coil end with a small axial protrusion length can be formed in a simple process.

(Embodiment 2)
In the first embodiment, the inter-coil connecting wire 300 in which the head crossing portion 305 shown in FIGS. 3 to 5 is formed in the final shape is twisted together with the undeveloped inner coil U-shaped conductor and outer coil U-shaped conductor. As a result, the skew crossing portions 303 and 304 and the head skew portion were formed.

  However, when twisting an undeveloped U-shaped conductor to form a head skew portion, virtual radiation (indicated by a one-dot chain line in FIG. 5) in which the head tip portion 17a extends in the radial direction. ) It is preferable to incline obliquely by a predetermined angle with respect to R. For example, in FIG. 5, the head tip portions 17a of the inner coil U-shaped conductor and the outer coil U-shaped conductor are inclined by about 20 degrees with respect to the radiation. For example, as described in Patent Document 20, this inclination of the U-shaped head end portion 17a is applied to the groove of the holder that holds the undeveloped U-shaped head end portion. Thus, this inclination can be realized by using the stress applied to the head tip portion 17a.

  In this case, even if the simultaneous twisting is performed while holding the head crossing portion 305 of the inter-coil connecting wire 300 using the same holder, the head crossing portion (head end portion) 305 of the inter-coil connecting wire 300 is performed. It is not easy to give the radial crossover portions 3052 and 3053 the same inclination as the head tip portion 17a. This is because the head crossover portion 305 of the inter-coil connecting wire 300 has a shape that is significantly different from the head tip portions of the inner coil U-shaped conductor and the outer coil U-shaped conductor. This is because the applied stress is different from the stress applied to the head tip portion 17a.

  Therefore, in this embodiment, after inserting the straight portion of the undeveloped inter-coil connecting wire 300 into the hole of the multiple rotating ring 400, the ring is preliminarily rotated while pressing the head connecting portion 305 in the axial direction. The inclination is given to the radial crossover portions 3052 and 3053 of the head crossover portion 305 of the inter-coil crossover wire 300. At this time, portions of the linear portion of the inter-coil connecting wire 300 that will later become the skew connecting portions 303 and 304 are also inserted into the holes of the multiple rotation ring 400, and the skew connecting portion 303 is obtained by this preliminary rotation. , 304 is preferably not skewed.

  In this way, the radial crossover portions 3052 and 3053 of the head crossover portion 305 are inclined in the circumferential direction from the connection point between the radial crossover portions 3052 and 3053 and the circumferential crossover portion 3051. Thereafter, the portions of the inter-coil connecting wire 300 to become the skew crossing portions 303 and 304 are extracted from the multiple rotation ring 400, and then the undeployed inner coil U-shaped conductor and outer coil U-shaped conductor are multiple-rotated. After inserting into the ring 400, simultaneous rotation (simultaneous twisting) is performed. Thereby, the difference in the inclination between the radial crossing portions 3052 and 3053 and the head end portion of the U-shaped conductor due to simultaneous twisting can be absorbed.

  Since the radial crossover portions 3052 and 3053 are slightly inclined by simultaneous rotation, the amount of inclination of the radial crossover portions 3052 and 3053 in the preliminary rotation, that is, the angle of preliminary deployment is the radial crossover portion by the simultaneous rotation. It should be set in consideration of the inclinations 3052 and 3053.

  According to this embodiment, the radius of curvature at the boundary between the leading end of the U-shaped conductor and the inter-coil connecting wire 300 and the head connecting portion 305 and the head skewing portion and the skewing connecting portions 303 and 304 is increased. Therefore, the tensile stress and compressive stress of the insulating resin film in the shoulder portions 106 and 107 can be reduced, and the damage and the deterioration of the electrical insulation performance can be reduced. Further, since the total extension distance of the head portion of the U-shaped segment can be shortened, the electrical resistance and leakage inductance of the head-side coil end can be reduced, thereby reducing heat generation and increasing output.

(Modification)
In addition, you may perform the said inclination of the above-mentioned head skew part of a U-shaped conductor by the independent head front-end | tip part twist process instead of performing by the stress in a simultaneous rotation process (this expansion | deployment process). Since this U-shaped conductor head tip pre-twisting process is described in detail in Patent Document 20, please refer to it if necessary.

(Embodiment 3)
A preferred embodiment of the above-described circumferential deployment method of the inter-coil connecting wire 300 in the arrangement example 2 will be described below.

  In the arrangement example 2 of the inter-coil connecting wire 300 shown in FIGS. 6 to 8, the pair of skew crossing portions 303 and 304 of the inter-coil connecting wire 300 are arranged at the conductor housing positions C <b> 2 and C <b> 7. Adjacent in the circumferential direction to the oblique part.

  The inter-coil connecting wire 300 of this arrangement example 2 can also be produced by the same method as in the first and second embodiments. FIG. 15A shows a state before the linear portion of the inter-coil connecting wire 300 shown in FIG. 6 is expanded (before the main expansion), and FIG. 15B is the same as FIG.

(Embodiment 4)
A further preferred embodiment of the circumferential direction developing method of the inter-coil connecting wire 300 of the arrangement example 2 described above will be described below.

  In the arrangement example 2 of the inter-coil connecting wire 300 shown in FIGS. 6 to 8, the pair of skew crossing portions 303 and 304 of the inter-coil connecting wire 300 are arranged at the conductor housing positions C <b> 2 and C <b> 7. Adjacent in the circumferential direction to the oblique part. What is important here is that the distal ends of the radial crossover portions 3052 and 3053 of the head crossover portion 305 of the inter-coil crossover wire 300 finally have a shape that sinks inward in the axial direction of the large segments 17x and 17y. .

  The holes of the rings 401 to 404 should be equidistant in the circumferential direction immediately before simultaneous deployment. Therefore, the pair of straight portions of the inter-coil connecting wire 300 should enter the holes on the radiations r1 and r4 (see FIG. 8) immediately before the simultaneous deployment. The leading ends of the crossover portions 3052 and 3053 are located at the positions of the radiations r2 and r3, and are shifted by a half pitch in the circumferential direction.

  In order to solve this problem, the straight line portion connected to the radial crossover portion 3052 of the inter-coil connecting wire 300 is previously twisted by an extra half slot pitch, and the straight portion continuous to the radial crossing portion 3053 of the inter-coil crossover wire 300 is formed. Twist an extra half slot pitch in advance.

  That is, the inter-coil connecting wire 300 in which the skew crossing portions 303 and 304 are not expanded is first inserted into the multiple rotation ring 400, and the skew crossing portion 303 is rotated by the half slot pitch of the rings 401 and 404. , 304 are inclined at half-slot pitch (preliminary development step). It should be noted that an extra straight line portion of the inter-coil connecting wire 300 to be the skew crossing portions 303 and 304 is previously extracted. Further, the holes of the rings 401 and 404 before the preliminary deployment are shifted by a half slot pitch with respect to the holes of the rings 402 and 403, and the holes of the respective rings 401 to 404 are aligned in the radial direction after the preliminary deployment. To do.

  Next, undeveloped normal U-shaped conductors (inner coil U-shaped conductor and outer coil U-shaped conductor) are inserted into the multiple rotation ring 400 to perform simultaneous rotation. This makes it possible to smoothly form the skew crossing portions 303 and 304 on the inter-coil connecting wire 300 and the head skew portion on the normal U-shaped conductor.

(Embodiment 5)
A preferred embodiment of the above-described circumferential deployment method of the inter-coil connecting wire 300 of the arrangement example 3 will be described below.

  In the arrangement example 3 of the inter-coil connecting wire 300 shown in FIGS. 9 to 11, the pair of skew crossing portions 303 and 304 of the inter-coil connecting wire 300 are arranged at the conductor housing positions C2 and C6. The skew crossing portion 303 is circumferentially adjacent to the head skew portion 27c on the radially inner side of the small segment 27 of the inner coil U-shaped conductor 27, and the skew crossing portion 304 is a small portion of the U-shaped conductor for the outer coil. It adjoins to the head skew part 27c inside the radial direction of the segment 27 in the circumferential direction.

  However, in this embodiment, a quadruple ring is used as the multiple rotation ring 400. Therefore, the pair of rings 401 and 403 for rotating the slot conductor portions at the conductor housing positions C2 and C6 rotate in the same direction, so As shown in FIG. 10, the pair of skew crossing portions 303 and 304 of the line 300 is skewed in the same circumferential direction.

  That is, in FIG. 11, among the head crossover portions 305 painted black, the radial crossover portion 3053 turns the circumferential crossover portion 3051 extending from the radial crossover portion 3052 in the clockwise direction counterclockwise. In order to connect to the skew crossing portion 304 (see FIG. 9) of the extending inter-coil connecting wire 300, it is necessary to reverse the direction by 180 degrees.

  For this reason, in this third embodiment, a predetermined slot is formed in the straight portion of the inter-coil connecting wire 300 in which the shape of the head crossover portion 305 is previously developed by press molding or the like, in the same manner as in the fourth embodiment. Preliminary formation of the pitch crossing portion is performed.

  This will be described more specifically. The holes of the rings 401 to 404 should be equidistant in the circumferential direction immediately before simultaneous deployment. Therefore, the pair of straight portions of the inter-coil connecting wire 300 should enter the holes on the radiations r4 and r5 (see FIG. 11) immediately before the simultaneous deployment, but the straight portion of the inter-coil connecting wire 300 (that is, the radial direction). The leading ends of the transition portions 3052 and 3053) are present at the positions of the radiations r2 and r3 (actually, the leading ends of the radial transition portions 3053 are further shifted in the clockwise direction from the radiation r3), and are shifted by a half pitch in the circumferential direction. ing. In order to solve this problem, the pair of straight portions connected to the radial crossing portions 3052 and 3053 may be twisted in advance by approximately a half slot pitch.

  That is, the head connecting part 305 is formed by press molding, and the skew connecting parts 303 and 304 are not yet formed (undeveloped) between the coil connecting wires 300 are first inserted into the rings 401 and 403, Thereafter, the ring 401, 403 is rotated counterclockwise by approximately a half slot pitch while prohibiting the circumferential movement of the head crossing portion 305, and the skew crossing portions 303, 304 are skewed by a half slot pitch. (Preliminary deployment process). It should be noted that the straight portions of the inter-coil connecting wire 300 to be the skew crossing portions 303 and 304 are previously extracted by an amount corresponding to the preliminary development. In addition, the holes of the rings 401 and 403 before the preliminary deployment are shifted by approximately a half slot pitch with respect to the holes of the rings 402 and 404, and the holes of the rings 401 to 404 are aligned in the radial direction after the preliminary deployment. To.

  Next, undeveloped normal U-shaped conductors (inner coil U-shaped conductor and outer coil U-shaped conductor) are inserted into the multiple rotation ring 400 to perform simultaneous rotation. This makes it possible to smoothly form the skew crossing portions 303 and 304 on the inter-coil connecting wire 300 and the head skew portion on the normal U-shaped conductor. Note that the preliminary rotation amount (preliminary twist amount) of the ring 403 may be set larger than that of the ring 401.

(Modification)
In the fifth embodiment described above, the quadruple multiple rotation ring 400 is used. For example, the ring that occupies the conductor housing position C1 and the ring that occupies the conductor housing position C2 are separated from each other. The ring occupying the accommodation position C5 and the ring occupying the conductor accommodation position C6 may be separate rings.

(Embodiment 6)
Another embodiment will be described with reference to FIG. The inter-coil connecting wire 300 connects, for example, a U-phase coil of the inner coil 100 and a U-phase coil of the outer coil 200 in series. At this time, there may be a case where the inter-coil connecting wire for the U-phase coil and the other two-phase inter-coil connecting wires need to overlap in the circumferential direction. In this case, the connecting wire between one coil is arranged on the lower layer in the axial direction, and the connecting wire between the other coils is arranged on the higher layer side in the axial direction, so that the two connecting wires between the coils do not overlap spatially. Can be. This multi-coil crossover wiring arrangement structure is referred to as a two-story structure. An example of this two-story structure is shown in FIG.

  In this case, the inter-coil connecting wire 300 having a small axial length and a small radial length is used on the lower layer side, and an inter-coil connecting wire 300 'having a large axial length and a large radial length is used on the high layer side. As a result, the crossover wires 300 and 300 'between the two coils can be crossed without interference.

A method for manufacturing the head-side coil end having the two-storied inter-coil connecting wires 300 and 300 ′ will be described below. In FIG. 16, the inter-coil connecting wire of the arrangement example 2 shown in FIGS. 6 to 8 is used as the inter-coil connecting wire 300, and the inter-coil connecting wire of the arrangement example 1 shown in FIGS. 3 to 5 as the inter-coil connecting wire 300 ′. Was used.
Therefore, the inter-coil connecting wire 300 ′ may be manufactured according to the first and second embodiments, and the inter-coil connecting wire 300 may be manufactured according to the third and fourth embodiments.

  In addition, when the preliminary deployment of the multiple rotation ring 400 is used for the preliminary deployment of the inter-coil crossover wires 300 and 300 ′, the preliminary deployment amount (circumferential deployment amount) of the inter-coil crossover wires 300 and 300 ′. Are equal, insert the inter-coil connecting wires 300, 300 ′ whose straight line portions are not yet developed into the multiple rotation ring 400, and preliminarily rotate the multiple rotation ring 400 to pre-deploy them all at once. Is preferred.

  In addition, two crossover coils crossing each other are used, the ring for preliminary deployment of these two coil crossover wires is the same, and the amount of preliminary deployment of the low-layer coil crossover wire is higher If it is larger than the pre-deployment amount of the inter-coil connecting wire, the inter-coil connecting wire on the lower layer side is previously inserted into the multi-rotation ring 400 and preliminarily developed by the first circumferential development amount. The connecting wire between the coils on the side is inserted into the multiple rotation ring 400, and it is preliminarily expanded by the second circumferential expansion amount. In this way, a pre-deployment amount equal to the first circumferential direction deployment amount + the second circumferential direction deployment amount is given to the low-layer coil connecting wire, and the second circumferential direction is applied to the high-layer coil connecting wire. Both preliminary deployments equal to the deployment amount can be given.

  In addition, when the low-layer coil connecting wire and the high-layer coil connecting wire are held on different rings of the multiple rotation ring 400 that can rotate independently of each other, the multiple coil connection wires are rotated multiple times. It is only necessary to insert the ring 400 and perform preliminary rotation of each ring by a necessary circumferential development amount.

  In addition, if a six-fold ring or an eight-fold ring, for example, is used instead of the four-fold multiple rotation ring 400 used in each embodiment, a low-layer side coil connecting wire and a high-layer side coil connecting wire 300 are respectively provided. A desired circumferential development amount can also be given.

1 is an axial cross-sectional view of a vehicle AC generator that employs a stator coil of Embodiment 1. FIG. It is a model perspective view of the U-shaped conductor pair for coils which consists of a large segment and a small segment. 6 is an axial schematic side view showing a head-side coil end structure of Arrangement Example 1. FIG. FIG. 4 is a partial circumferential development of the head-side coil end of FIG. 3. It is the partial front view which looked at the head side coil end of FIG. 3 from back. It is an axial direction schematic side view which shows the head side coil end structure of the example 2 of an arrangement | positioning. FIG. 7 is a partial circumferential development of the head-side coil end of FIG. 6. It is the partial front view which looked at the head side coil end of FIG. 6 from back. It is an axial direction schematic side view which shows the head side coil end structure of the example 3 of an arrangement | positioning. FIG. 10 is a partial circumferential development of the head-side coil end of FIG. 9. It is the partial front view which looked at the head side coil end of FIG. 9 from back. (A) is a schematic half plan view showing a multiple rotation ring used for circumferential development (twisting) of a U-shaped conductor, and (b) is a schematic radial sectional view. It is a schematic process diagram which shows Production Example 1 of the connecting wire between coils. It is a schematic process figure which shows the manufacture example 2 of a connecting wire between coils. It is a model axial sectional view which shows the axial direction sink state of the connecting wire between coils in Embodiment 3, (a) is before this expansion | deployment, (b) shows after this expansion | deployment. It is a schematic diagram which shows the two-story coil crossover structure of Embodiment 6, (a) is an axial schematic side view which shows the head side coil end structure before this expansion | deployment in the example 2 of arrangement | positioning, (b) is an example of arrangement | positioning. 2 is a schematic axial side view showing a head-side coil end structure after the main deployment in FIG.

Explanation of symbols

17 Large segment 17a Head tip portion 17b Head skew portion 17c Head skew portion 27 Small segment 27a Head tip portion 27b Head skew portion 27c Head skew portion 100 Inner coil 200 Outer coil 300 Spacing between coils Line 301 Slot conductor portion 302 Slot conductor portion 303 Skew crossover portion 304 Skew crossover portion 305 Head crossover portion 3051 Circumferential crossover portion 3052 Radial crossover portion 3053 Radial crossover portion 400 Multiple rotation rings 401 to 404 Ring

Claims (5)

An outer coil formed by sequentially connecting a number of developed U-shaped conductors, each having a U-shaped head tip and a head skew portion developed in the circumferential direction from both ends of the head tip, in series, A number of developed U-shaped conductors each having a U-shaped head tip portion and a head skew portion developed in the circumferential direction from both ends of the head tip portion are sequentially connected in series. An expanded coil connecting wire having an inner coil disposed radially inward, a substantially U-shaped head distal end portion, and a head oblique portion deployed in the circumferential direction from both ends of the head distal end portion. In a method of manufacturing a U-shaped conductor sequential joining stator coil having a U-shaped conductor and having an inter-coil connecting wire connecting the outer coil and the inner coil in series for each phase,
U-shaped conductor for inner coil and U-shaped conductor for outer coil each having a U-shaped head tip and a pair of straight portions extending in parallel from both ends of the head tip. And a U-shaped conductor preparation step of preparing a U-shaped conductor for the connecting wire between the coils,
A pre-expansion step of processing the tip of the head portion of the U-shaped conductor for connecting wires between the coils to set a distance between a pair of straight portions of the U-shaped conductor for connecting wires to a predetermined pre-circumferential direction expansion amount;
A pair of straight portions of the U-shaped conductor for the outer coil are individually held by a plurality of outer rings, a pair of straight portions of the U-shaped conductor for the inner coil are individually held by a plurality of inner rings, The outer coil U-shaped conductor is rotated by relatively rotating the outer ring and the inner ring which are coaxial with each other while the pair of straight portions of the U-shaped conductor for wire are individually held by the outer ring and the inner ring. , A main development step of forming the head skew portion in the inner coil U-shaped conductor and the inter-coil connecting wire U-shaped conductor;
A method of manufacturing a U-segment sequentially joined stator coil. In the manufacturing method of the U-shaped segment sequential joining stator coil of Claim 1,
The preliminary deployment step includes
After individually holding a pair of straight portions of the undeveloped U-shaped conductor for the inter-coil coil between the outer ring and the inner ring, by rotating the outer ring and the inner ring, A manufacturing method of a U-segment sequential joining stator coil which gives a predetermined amount of development in the preliminary circumferential direction to a head end portion or a straight portion of a U-shaped conductor. In the manufacturing method of the U-segment sequential joining stator coil of Claim 2,
The connecting wire between the coils is located between the inner coil and the outer coil and extends in the circumferential direction, and extends in the radial direction from both sides of the circumferential extension portion. A pair of radially extending portions extending in the direction by a predetermined circumferential expansion amount,
The pre-deployment step is a manufacturing method of a U-segment sequential joining stator coil that gives the predetermined circumferential development amount to a pair of radially extending portions or a pair of linear portions of the inter-coil connecting wire. In the manufacturing method of the U-shaped segment sequential joining stator coil of Claim 1,
The U-shaped conductor preparation step includes
Preparing a plurality of U-shaped conductors for connecting between the coils to connect the inner coil and the outer coil;
In the preliminary development step, after a part of the plurality of U-conductors for connecting wires between the coils is preliminarily developed, the remaining portion is developed by the additional pre-expansion step or the main development step, and the U-segment sequential joining stator Coil manufacturing method. In the manufacturing method of the U-shaped segment sequential joining stator coil of Claim 4,
Of the plurality of inter-coil connecting wires, a U-segment sequential joining stator coil in which the inter-coil connecting wire having a longer radial distance is disposed axially outside the inter-coil connecting wire having a shorter radial distance. Production method.

Images