JP6149395B2 - Rotating electric machine for vehicles - Google Patents

Description

  The present invention relates to a vehicular rotating electrical machine mounted on a passenger car, a truck, or the like.

  Conventionally, it has a structure in which the stator and rotor are directly cooled by a refrigerant, and a heat radiation path made of a material having high thermal conductivity is provided in the stator coil slot, so that the coil inside the slot and the outside coil are connected. An electric motor with a reduced temperature difference is known (for example, see Patent Document 1). The heat dissipation path is intended to reduce the size and weight of the motor by reducing the difference in coil temperature between the inside and outside of the stator core.

JP-A-8-205477

  By the way, in the electric motor of patent document 1 mentioned above, in order to cool a coil (stator winding), another part as a heat dissipation path is needed, and while the number of parts increases, it is necessary to add the assembly process. There was a problem. The addition of these separate parts and the addition of an assembly process lead to an increase in manufacturing cost, which is not desirable.

  The present invention was created in view of the above points, and an object thereof is a vehicle capable of efficiently cooling a stator winding without requiring addition of another part or addition of an assembly process. It is to provide a rotating electrical machine for use.

In order to solve the above-described problem, a rotating electrical machine for a vehicle according to the present invention includes a stator and a rotor. The stator has a plurality of slots and is formed in a ring shape, and a stator winding wound around the stator core in a state of being unevenly distributed on the inner diameter side in the slots; A sheet-like insulating member that has a shape along the inner peripheral surface of the slot and electrically insulates the stator core and the stator winding, and the stator winding is unevenly distributed on the inner diameter side in the slot. And a cooling medium path formed in the slot by a space generated on the outer diameter side. The rotor is disposed opposite to the inner diameter side of the stator core. The rotor has a cooling fan fixed to the end face in the axial direction of the pole core, and the cooling medium passing through the cooling medium path is cooling air generated by the cooling fan as the rotor rotates.

  In each slot of the stator core, the stator winding is arranged close to the inner diameter side to form the cooling medium path on the outer diameter side, so no separate parts are required to form this cooling medium path. In addition, it is possible to efficiently cool the entire stator winding while omitting the process of assembling the separate parts. Thereby, while reducing manufacturing cost, the output accompanying cooling can be improved. In addition, by arranging the stator winding close to the inner diameter side in the slot of the stator core, the total length of the stator winding can be shortened, and the amount of copper to be used can be reduced. Furthermore, since the stator winding is unevenly distributed on the inner diameter side, a gap between a part (specifically, a front side frame or a rear side frame) arranged outside the stator winding and a coil end is reduced. It becomes easy to spread, and the environmental resistance against moisture can be improved.

It is sectional drawing which shows the whole structure of the alternating current generator for vehicles of one Embodiment. It is a figure which shows the arrangement | positioning state of the insulation member accommodated in a slot, a stator winding | coil, and a cooling medium path | route. It is a perspective view of a rotor. It is a top view of the cooling fan of the front side. It is the expanded view which looked at the stator from the outside. It is a figure which shows the modification of the stator which made circular cross-sectional shape.

  Hereinafter, an automotive alternator according to an embodiment to which a rotating electrical machine for a vehicle of the present invention is applied will be described in detail with reference to the drawings. A vehicle alternator 1 according to one embodiment shown in FIG. 1 includes a stator 2, a rotor 3, a brush device 4, a rectifier 5, a frame 6, a rear cover 7, a pulley 8, and the like.

  The stator 2 includes a stator core 21 formed in a ring shape having a plurality of slots 22, and a three-phase stator winding 23 wound around each slot 22 of the stator core 21 at a predetermined interval. And a sheet-like insulating member 24 that electrically insulates the stator core 21 and the stator winding 23, and a cooling medium path 25 formed in the slot 22.

  As shown in FIG. 2, the insulating member 24 has a shape along the inner peripheral surface of the slot 22. In the slot 22, a plurality of conductors constituting the stator winding 23 are wound around the stator core 21 in a state of being arranged unevenly on the inner diameter side. In this way, the cooling medium path 25 is formed in the slot 22 by the space generated on the outer diameter side by arranging the stator windings 23 in the slot 22 so as to be unevenly distributed on the inner diameter side.

  The cross-sectional shape of the plurality of conductors constituting the stator winding 23 is a rectangular shape (rectangular shape) at least in the slot 22. In addition to the case where the entire stator winding 23 is configured using a conductor having a rectangular cross section, the stator winding 23 exposed to the outside of the slot 22 is configured using a conductor having a circular or elliptical cross section. Only in the slot 22, a conductor having a flat cross section may be used.

  The rotor 3 is disposed opposite to the inner diameter side of the stator core 21. The rotor 3 has a structure in which a field winding 31 in which an insulated copper wire is wound in a cylindrical and concentric manner is sandwiched from both sides through a rotating shaft 33 by a pole core 32 having a plurality of magnetic pole claws. have. A cooling fan 34 is attached to the axial end surface of the pole core 32 on the front side by welding or the like. Similarly, a cooling fan 35 is attached to the axial end surface of the rear pole core 32 by welding or the like.

  As shown in FIGS. 3 and 4, in this embodiment, the cooling fan 34 on the front side on the pulley 8 side is a mixed flow fan. The cooling fan 34 is formed by press-molding a plate material such as an iron plate, and is formed by cutting and raising a part of the base part 34A parallel to the axial end surface of the pole core 32 on the rear side. Blade portion 34B. The angle at which the blade portion 34B is raised (the angle between the base portion 34A and the blade portion 34B) is set to an angle of less than 90 degrees. As shown in FIG. 3, the rear cooling fan 35 is a centrifugal fan having an angle of 90 ° for raising the blade portion. Further, as shown in FIG. 1, the height of the cooling fans 34 and 35 described above (the height along the rotation shaft 33 at the tip of the blade portion) is higher than the coil end height of the stator winding 23. .

  The brush device 4 is for passing an exciting current from the rectifying device 5 to the field winding of the rotor 3 to the field winding 31, and is pressed against each of the slip rings 36 and 37 formed on the rotating shaft 33 of the rotor 3. Brushes 41 and 42 to be used. The rectifier 5 is for rectifying the three-phase AC voltage, which is the output voltage of the three-phase stator winding 23, to obtain DC output power, and is fixed to the outer end surface of the rear frame 6. Yes.

  The frame 6 accommodates the stator 2 and the rotor 3, is supported in a state where the rotor 3 can rotate around the rotation shaft 33, and a predetermined amount is provided on the outer peripheral side of the pole core 32 of the rotor 3. A stator 2 arranged via a gap is fixed. The frame 6 has a cooling air discharge window 61 at a portion facing the coil end of the stator winding 23 protruding from the axial end surface of the stator core 21 and a cooling air suction window 62 at the axial end surface. Is provided. The rear cover 7 covers the entire brush device 4, the rectifying device 5, and the control device 12 as electrical components attached to the outside of the rear-side frame 6 and protects them.

  In the vehicle alternator 1 having the above-described structure, the rotor 3 rotates in a predetermined direction when a rotational force from an engine (not shown) is transmitted to the pulley 8 via a belt or the like. In this state, by applying an excitation voltage from the outside to the field winding 31 of the rotor 3, each claw portion of the pole core 32 is excited, and a three-phase AC voltage can be generated in the stator winding 23. DC output power is taken out from the output terminal of the rectifier 5.

  In addition, cooling air is generated by the cooling fans 34 and 35 as the rotor 3 rotates. Specifically, when the cooling fan 34 on the front side, which is a mixed flow fan, rotates, the air in the external space is sucked from the suction window 62 of the frame 6 on the front side, and the cooling air flows to the outer diameter side of the cooling fan 34. Is sent out. Since the cooling fan 34 is a mixed flow fan, the cooling air sent to the outer diameter side includes a component sent in an oblique direction in addition to a component sent in the radial direction. For this reason, the air volume of the cooling air flowing along the axial direction (direction parallel to the rotation shaft 33) can be increased. A part of the cooling air flowing along the axial direction is used as a cooling medium passing through the cooling medium path 25. The cooling air sent out in the radial direction by the cooling fan 34 cools the coil end on the front side of the stator winding 23 and is then discharged mainly from the discharge window 61 of the frame 6 on the front side. Are supplied to the cooling medium path 25.

  Further, when the cooling fan 35 on the rear side rotates, the cooling air can be introduced into the rear cover 7 through the suction window (not shown) of the rear cover 7. The cooling air cools the brush device 4, the rectifying device 5, and the control device 12 as electrical components, and then is sucked into the frame 6 from the suction window 62 of the rear frame 6, and is moved to the outer diameter side of the cooling fan 35. Sent out. The cooling air cools the coil end on the rear side of the stator winding 23 and is then discharged from the discharge window 61 of the frame 6 on the rear side.

  Further, as shown in FIG. 5, at least at the root portion of the coil end of the stator winding 23, the cooling air generated by the cooling fan 34 is generated by the clearance S <b> 1 through which the cooling air is passed from the inner diameter side to the outer diameter side and the cooling fan 35. A clearance S2 is formed to allow the cooling air to pass from the inner diameter side to the outer diameter side.

  Thus, in the vehicle alternator 1 of the present embodiment, the cooling medium path 25 is provided on the outer diameter side by disposing the stator winding 23 close to the inner diameter side in each slot 22 of the stator core 21. Therefore, no separate part is required to form the cooling medium path 25, and the entire stator winding 23 can be efficiently cooled after the step of assembling the separate part is omitted. Thereby, while reducing manufacturing cost, the output accompanying cooling can be improved. Further, by placing the stator winding 23 close to the inner diameter side in the slot 22 of the stator core 21, the overall length of the stator winding 23 can be shortened, and the amount of copper used can be reduced. . Further, since the stator windings 23 are unevenly distributed on the inner diameter side, components (specifically, the front side and rear side frames 6) arranged outside the stator windings 23 and the coils of the stator windings 23 are arranged. It becomes easy to widen the gap between the ends, and the environmental resistance against moisture can be improved.

  Further, by using the cooling air generated by the cooling fans 34 and 35 along with the rotation of the rotor 3 as the cooling medium passing through the cooling medium path, the cooling medium path 25 is cooled using the rotor 3 having the same structure as the conventional one. It becomes possible to supply a medium (cooling air), and no additional parts are required.

  Further, by using one of the cooling fans 34 as a mixed flow fan, the amount of cooling air flowing along the axial direction can be increased, and the amount of cooling air flowing through the cooling medium path 25 can also be increased. Can be obtained. In particular, by using the cooling fan 34 on the front side as a mixed flow fan, not the cooling air after cooling other components (such as the rectifier 5), but the cooling air taken from the external space to the cooling medium path 25. It becomes possible to supply, and the cooling effect can be further enhanced.

  In addition, since the cooling fans 34 and 35 are made higher than the coil end height of the stator winding 23, the cooling air easily jumps to the outer diameter side over the coil end, and the outer diameter side of the coil end. Can be efficiently cooled, and the cooling air can be efficiently supplied to the cooling medium path 25 formed on the outer diameter side of the stator winding 23.

  Further, the cross-sectional shape of the conductor constituting the stator winding 23 is a rectangular shape at least in the slot 22. Thereby, compared with the case where the cross-sectional shape is a round shape, the stator windings 23 can be packed and arranged in the slot 22 to reduce the dead space, and the resistance value of the stator windings 23 is not changed. The cooling medium path 25 can be widened, and a larger cooling effect can be obtained.

  In addition, by providing gaps S1 and S2 communicating in the radial direction at the root of the coil end of the stator winding 23, the cooling performance of the coil end is improved and the coil end passes from the inner diameter side toward the outer diameter side. Since the cooled cooling air can be guided to the cooling medium path 25, the cooling performance of the stator winding 23 can be further improved.

  In addition, this invention is not limited to the said embodiment, A various deformation | transformation implementation is possible within the range of the summary of this invention. For example, in the above-described embodiment, the front-side cooling fan 34 is a mixed flow fan. However, as with the rear-side cooling fan 35, a centrifugal fan whose angle of raising the blade portion is 90 ° may be used. Good. In that case, it is desirable that the two cooling fans 34 and 35 on the front side and the rear side have a difference in fan capacity (air volume). For example, it may be possible to provide a difference in fan capacity by changing the area and number of blade portions. By providing a difference in the fan capacity (air volume) of each of the pair of cooling fans 34 and 35, it becomes easy to generate a flow of cooling air along the axial direction according to the difference in fan capacity. Thus, it is possible to flow the cooling air through the cooling medium path 25 without providing the supply mechanism.

  In the embodiment described above, the AC generator for a vehicle has been described. However, the present invention is also applied to other rotating electrical machines for vehicles, for example, a rotating electrical machine that performs an electric operation and a rotating electrical machine that performs both a power generation operation and an electric operation. Can be applied.

  In the above-described embodiment, the cross-sectional shape of the plurality of conductors constituting the stator winding 23 in the slot 22 is a rectangular shape. However, as shown in FIG. 6, the conductors constituting the stator winding 23 The cross-sectional shape may be circular (or elliptical). As described above, even when the cross-sectional shape of the conductor is circular, the cooling medium path 25 is provided on the outer diameter side by disposing the stator winding 23 toward the inner diameter side in each slot 22 of the stator core 21. Can be formed.

  As described above, according to the present invention, the cooling medium path is formed on the outer diameter side by disposing the stator winding close to the inner diameter side in each slot of the stator core. A separate part is not required to form the path, and the entire stator winding can be efficiently cooled while omitting the step of assembling the separate part.

DESCRIPTION OF SYMBOLS 1 AC generator for vehicles 2 Stator 21 Stator iron core 22 Slot 23 Stator winding 25 Cooling medium path | route 3 Rotor 34, 35 Cooling fan

Claims (7)

A stator core (21) formed in a ring shape having a plurality of slots (22), and a stator wound around the stator core in a state of being unevenly distributed on the inner diameter side in the slot A winding (23), a sheet-like insulating member (24) having a shape along the inner peripheral surface of the slot and electrically insulating the stator core and the stator winding; and in the slot A stator (2) having a cooling medium path (25) formed in the slot by a space created on the outer diameter side by arranging the stator windings unevenly on the inner diameter side;
A rotor (3) disposed opposite to the inner diameter side of the stator core;
The rotor has a cooling fan (34, 35) fixed to the axial end face of the pole core (32);
The cooling medium through the cooling medium path, the rotary electric machine for a vehicle, wherein a cooling air der Rukoto generated by the cooling fan with the rotation of the rotor. In claim 1 ,
A pair of cooling fans is provided on both axial end surfaces of the pole core,
One of a pair of said cooling fans is a mixed flow fan (34), The rotary electric machine for vehicles characterized by the above-mentioned. In claim 2 ,
Front and rear frames (6) for accommodating the rotor in a rotatable state;
A rotating electrical machine for a vehicle, wherein the cooling fan corresponding to the front frame is the mixed flow fan. In claim 1 ,
A pair of cooling fans is provided on both axial end surfaces of the pole core,
A vehicular rotating electrical machine characterized in that there is a difference in fan performance between the pair of cooling fans. In any one of claims 1 to 4,
The rotating electrical machine for a vehicle according to claim 1, wherein a height of the cooling fan is higher than a coil end height of the stator winding. In any one of Claims 1-5 ,
The rotating electrical machine for a vehicle according to claim 1, wherein a cross-sectional shape of a conductor constituting the stator winding is a rectangular shape at least in the slot. In any one of claims 1 to 5,
A rotating electrical machine for a vehicle according to claim 1, wherein a gap is formed at least at a root portion of a coil end of the stator winding through which cooling air generated by the cooling fan passes from the inner diameter side to the outer diameter side.

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