JP2007295763A - Rotating electrical machine stator and AC generator - Google Patents

Abstract

The space factor of a stator coil in a slot in a stator can be improved, and the stator coil can be easily wound in the slot.
According to the present invention, a core is constituted by an annular outer core and an inner core in which a plurality of slots around which a stator coil is periodically wound is opened to the outer peripheral side, and the slots are arranged in a row. The inner periphery side to the outer periphery opening end were formed to have substantially the same width so as to be aligned. For this reason, the space factor of the stator coil in a slot can be improved. In addition, since the outer peripheral opening of each slot can be separated in the circumferential direction, it can be prevented from being accidentally inserted into the adjacent slot when the stator coil is wound, and the stator coil can be easily inserted into the slot. Can be wound.
[Selection] Figure 4

Description

  The present invention relates to a stator for an electric rotating machine and an AC generator.

  As an example in which a rotating electrical machine is mounted, an automobile will be described as an example. In recent years, automobiles tend to widen the interior of a vehicle without increasing the size of the vehicle itself. Therefore, each component must be mounted in a narrow space, and there is a demand for downsizing. However, as a rotating electrical machine, the size must be reduced while maintaining or improving efficiency. Such demands for both miniaturization and high efficiency are not limited to automobiles, but also apply to other products.

  Here, in order to achieve both reduction in size and high efficiency of the rotating electrical machine, there has been a demand for a higher space factor of a stator coil wound in a slot provided in a stator. However, in order to facilitate the formation of a magnetic path between the stator core and the rotor, it is necessary to narrow the innermost circumferential slot width of the stator core with respect to the slot width of the winding portion of the stator coil. There was a limit in inserting the stator coil with the insulating coating from the inner peripheral side without damaging it.

  Therefore, as shown in Patent Document 1, the stator core is divided into an inner core having a plurality of slots opened on the outer periphery and a cylindrical outer core attached to the outer periphery of the inner core, and the stator coil is separated from the outer periphery of the inner core. After mounting in the slot, the outer core is mounted to form the stator, whereby the space factor of the stator coil in the slot can be improved.

JP 2005-295610 A

  However, in Patent Document 1, since the stator coils are wound in a plurality of layers in the slot, the gap generated between the adjacent stator coils is relatively increased. Here, it is conceivable that the slots are narrowed and wound so that the stator coils are arranged in a row. However, the slot of Patent Document 1 is a substantially sector shape in which the outer circumferential side has a larger circumferential width than the inner circumferential side. Therefore, even if the stator coils are wound in a line, the gap between the stator coils cannot be reduced. For this reason, the space factor of the stator coil in a slot cannot be improved. Furthermore, when the number of slots is increased so that the stator coils are arranged in a line, if the circumferential width of the outer peripheral opening of the slot is large, the stator coil is erroneously inserted into the adjacent slot when the stator coil is wound. Will also occur.

  An object of the present invention is to provide a stator and an alternator for a rotating electrical machine that improve the space factor of the stator coil in the slot and easily wind the stator coil in the slot.

  The slots in the stator of the rotating electrical machine of the present invention are characterized in that the inner coil side to the outer peripheral opening end are formed with substantially the same width so that the stator coils are arranged in a line.

  Also, between the slots in the stator of the rotating electrical machine of the present invention, there is provided a substantially sector-shaped tooth whose outer peripheral side is wide from the inner peripheral position to the outer peripheral end of the mounting position of the stator coil. The width of the stator coil is larger than the width of the stator coils, and smaller than the width of the stator coils of two.

  In addition, the stator slot used in the AC generator of the present invention is characterized in that the stator coils are formed substantially in parallel from the inner peripheral side to the outer peripheral opening end in the width in which the stator coils are arranged in a line.

  According to the present invention, the space factor of the stator coil in the slot in the stator can be improved, and the stator coil can be easily wound in the slot.

  As an embodiment in which the rotating electrical machine of the present invention is used, an automotive alternator will be described. FIG. 1 is a side sectional view of the overall configuration of an automotive alternator.

  A pulley 2 as a rotation transmission member is fixed to one end side of the drive shaft 1 so as to rotate integrally with a bolt 3, and is connected to the pulley 2 from an engine as a drive source through an endless transmission band such as a belt. Rotational force is transmitted. The rotation transmission member can be a sprocket and the endless transmission band can be a chain.

Two serrations 4a and 4b are formed at a substantially central portion in the axial direction of the drive shaft 1 with a predetermined interval therebetween, and a Landel type iron core 5 as a rotor can rotate integrally with these serrations 4a and 4b. Has been inserted. The Landel iron core 5 includes two magnetic members 5a,
5b, and each magnetic member 5a, 5b engages with each serration 4a, 4b in the drive shaft 1 and has a shaft portion 7a having insertion holes 6a, 6b for restricting relative rotation.
7b, plate portions 8a and 8b provided at one end of the shaft portions 7a and 7b, and a plurality of tapered claws 9 extending substantially axially from the plate portions 8a and 8b (in the embodiment, each The magnetic members 5a and 5b are alternately provided with claws 9 so as to face each other, and the ends of the shaft portions 7a and 7b are arranged between the ends of the shaft portions 7a and 7b. Abut and are fixed to the drive shaft 1. The magnetic members 5a and 5b are restricted from moving in the axial direction by causing the material at both ends to plastically flow in the annular grooves 10a and 10b formed in the drive shaft 1.

  A field coil 11 with an insulation coating is wound between the shaft portions 7 a and 7 b of the Landell-type iron core 5 and the claws 9. Both terminal wires of the field coil 11 are connected to the drive shaft 1. A field current that is connected to the two slip rings 12 provided on the end side and controlled to obtain necessary power generation via the brush 13 is supplied from the outside. When a current is supplied to the field coil 11, a magnetic field is generated around the field coil 11 and a magnetic path is formed in the Landel type iron core 5.

A stator core 14 made of a magnetic material is disposed on the outer periphery of the Landell-type iron core 5 as a rotor via a predetermined gap, and a plurality of phases (in the plurality of slots 15 provided in the circumferential direction of the stator core 14 ( In this embodiment, a stator coil 16 having a six-phase insulating coating is wound. For this reason, when a current is supplied to the field coil 11, a magnetic path is formed across the Landel-type iron core 5 and the stator core 14, so that an AC voltage is generated in the stator coil 16 when the rotor rotates. The stator coil 16 has a circular cross section.

  The three-phase AC voltage generated in the stator coil 16 is rectified by a positive side diode and a negative side diode as a rectifier circuit provided on the opposite side of the pulley 2 in the axial direction, and a direct current is taken out from the output terminal 28. The negative side diode is provided on the negative side heat radiating plate 17a, and the positive side diode is fixed to the positive side heat radiating plate 17b which is overlapped with the negative side heat radiating plate 17a.

  The stator core 14 is sandwiched and fixed by a bolt (not shown) between a hook-shaped front housing 18 provided on the pulley 1 side and a hook-shaped rear housing 19 provided on the slip ring 12 side. Brackets 18a and 19a for fixing to the vehicle are provided on the outer peripheral sides of the front housing 18 and the rear housing 19, and the drive shaft 1 is rotatably supported on the inner peripheral side. Ball bearings 21a and 21b are fixed to the housings 18 and 19, respectively. In addition, a rear cover 20 that is housed inside the rear housing 19 is secured with bolts so as to protect the slip ring 12, the brush 13, the rectifying element, the negative-side radiator plate 17a, the positive-side radiator plate 17b, and the like. These front housing 18, rear housing 19 and rear cover 20 are formed of a nonmagnetic aluminum alloy.

  Next, details of the stator as an embodiment of the present invention will be described with reference to FIGS. FIG. 2 is a perspective view of a stator around which a stator coil is wound, FIG. 3A is a perspective view of an inner core in the stator, and FIG. 3B is a perspective view of an outer core in the stator. FIG. 4 is an enlarged view of the slot portion of the stator as a cross section.

  As shown in FIGS. 2 and 3, (a) and (b), the stator 22 includes an inner core 14a disposed on the inner periphery and an outer core 14b disposed on the outer periphery of the inner core 14a. The stator coil 16 is wound around the inner core 14a.

As shown in FIG. 3A, the inner core 14 a has a groove shape that radially opens between the teeth 23 on the outer peripheral side by arranging a plurality of teeth 23 (72 in this embodiment) radially. A plurality of slots 15 (72 in the present embodiment) are formed in the circumferential direction, and the slots 15 are also opened on the inner circumferential side with a narrower width in the circumferential direction than the outer circumferential side. That is, each tooth 23 is provided independently, and, as shown in FIG. 4, a tooth bridge 26 is formed at the inner peripheral end of each tooth 23 so as to protrude on both sides in the circumferential direction. Moreover, the outer peripheral end surface of each tooth 23 is formed in a circular arc shape so that the outer peripheral surface of the entire inner core 14a has a cylindrical shape.

The slot 15 linearly extends from the inner peripheral side excluding the tooth bridge 26 into which the stator coil 16 cannot be inserted to the outer peripheral opening end with substantially the same width, and the circumferential side surfaces of the adjacent teeth 23 are substantially parallel to each other. . In addition, the stator coil 16 is wound in the slot 15 in a state where the insulating paper 25 is wound. However, the width of the stator coil 16 is larger than the width of one slot 15, and 2 of the stator coil 16. The stator coil 16 is formed so as to be aligned in a line within the slot 15. By forming the slot 15 in this manner, each tooth 23 has a substantially sector shape in which the outer peripheral end side is wider in the circumferential direction than the inner peripheral side except for the tooth bridge 26 into which the stator coil 16 cannot be inserted.

  Next, the outer core 14b will be described. The outer core 14b is constituted by a so-called dust core formed by coating magnetic powder with a material such as an insulating material and a resin as a binder, and then compressing it with a molding die.

  As shown in FIG. 3B, the outer core 14b is formed in an annular cylindrical shape, that is, in an annular shape, and all the corresponding portions of the teeth 23 of the inner core 14a on the inner peripheral side open to the inner peripheral side. Concave portions 24 are formed radially along the axial direction. In addition, the concave portion 24 has an inner peripheral opening that is narrower in the circumferential direction than the outer peripheral bottom so as to correspond to the shape of the outer peripheral end of the tooth 23, and the outer peripheral bottom surface is circular like the outer peripheral end surface of the tooth 23. It is formed in a substantially fan shape that is arcuate. The outer peripheral ends of the teeth 23 of the inner core 14a are mounted in the recesses 24 thus formed. .

The inner core 14a and the outer core 14b configured as above are formed by pressing the outer peripheral side of each tooth 23 of the inner core 14a around which the stator coil 16 is wound into the recess 24 of the outer core 14b from the axial direction. A stator core 14 as shown in FIG.

  Next, the operation of the automotive alternator and the magnetic path formed in the stator core will be described with reference to FIGS.

  In order for the automotive alternator to generate power, first, a rotational force is transmitted to the pulley 2 from a driving source such as an engine via a belt. The rotation of the pulley 2 causes the Landel-type iron core 5 as a rotor and the field coil 11 mounted therein to rotate with respect to the stator core 14 via the drive shaft 1. In such a state where the rotor is simply rotating, power generation is not performed, but when a direct current is supplied to the field coil 11 from the outside via the brush 13 and the slip ring 12, the field coil 11 is surrounded. A magnetic field is formed. Therefore, the Landel-type iron core 5 is provided so as to surround the field coil 11, and the claws 9 alternately extend in the circumferential direction from both ends in the axial direction, so that different magnetic poles are provided between the claws 9 adjacent in the circumferential direction. It is formed.

  Here, since the magnetic flux formed in the Landel iron core 5 loses its place at the tip of the claw 9, it tends to flow to the claw 9 adjacent in the circumferential direction, but from the gap between the claw 9 adjacent in the circumferential direction. In addition, since the gap between the inner core 14a facing the outer peripheral surface of the claw 9 and the teeth 23 is smaller, most of the magnetic flux flows to the teeth 23 side.

Further, since the adjacent tooth bridges 26 on the inner peripheral side of the tooth 23 are separated from each other, the magnetic flux flowing in the tooth 23 shown in FIG. 4 flows to another tooth 23 via the outer core 14b, and further the rotor. A magnetic path is formed so as to return to the Landel-type iron core 5. At this time, since the teeth 23 and the outer core 14b are originally separate members, it is difficult to form a magnetic path. However, since the circumferential width of the outer peripheral side end of the teeth 23 is increased, the magnetic path area is increased. A sufficient magnetic path can be formed. Thus, a voltage is generated in the stator coil 16 by forming a magnetic path around the stator coil 16. Since the Landell type iron core 5 is rotating and the stator coil 16 has three phases, the generated voltage is a three-phase AC voltage, but is full-wave rectified by a rectifier circuit and converted into a DC voltage. The The DC power generated in this way is supplied to a battery (not shown) via the output terminal 28. Each tooth 23 is attracted to the rotor side by forming a magnetic path, but the circumferential width of the inner circumferential side opening of the recess 24 is smaller than the circumferential width of the outer circumferential end of the tooth 23. Therefore, the inward movement of the teeth 23 is prevented as much as possible.

  Further, the current supplied to the field coil 11 is controlled in accordance with the load capacity of the vehicle and the remaining amount of the battery, thereby preventing a decrease in the battery life due to excessive power supply. Thus, the electric power generated in the stator coil 16 varies in accordance with the state of the battery, the rotational speed, and the like.

  Next, a method for manufacturing a stator core will be described with reference to FIGS. FIG. 5 is an enlarged view of the original shape of the inner core as a cross section. FIG. 6 is a view in which a stator coil is wound around the original shape of the inner core. FIG. 7 is a view in which the outer core is fixed to the original shape of the inner core.

First, the original shape of the inner core 14a as shown in FIG. 5 is formed by putting the magnetic powder coated with the insulation coating into a mold and compressing it. In this original form, the teeth 23 are connected on the inner peripheral side, and all the teeth 23 are integrated in an annular shape. Moreover, the outer peripheral side of the location where each tooth | gear 23 is connected is each recessed, and this recessed part is shape | molded simultaneously with a shaping | molding die, when shape | molding the original form of the inner core 14a. In addition, although the part which protrudes in the circumferential direction from each tooth | gear 23 is provided in the circumferential direction both sides on both sides of this concave-shaped part, this site | part becomes the teeth bridge 26 finally.

A stator coil 16 is wound around the original shape of the inner core 14a thus formed as shown in FIG. The stator coil 16 is inserted from the outer peripheral side of the inner core 14a in a state where four bundles arranged in a row and the insulating paper 25 is wound, and coils for six phases are distributed in six adjacent slots 15. It is wound with wave winding as a winding.

Next, as shown in FIG. 7, the outer core 14b is fitted into the outer periphery of the inner core 14a from the axial direction so that the teeth 23 of the inner core 14a are fixed in the recess 24 of the outer core 14b. As shown in (b), the inner core 14a and the outer core 14b are integrated. In addition, since it is easier to form a magnetic path if the inner core 14a and the outer core 14b are closely contacted with each other, it is better that the outer core 14b is slightly deformed during press-fitting.

  The stator core 14 manufactured in this way is in a state where the teeth 23 are connected to each other on the inner periphery of the inner core 14a, but the connecting portion is removed by cutting as shown in FIG. For this reason, each tooth | gear 23 is cut | disconnected in the state in which the teeth bridge 27 was formed. In addition, when performing a cutting process, it is necessary to interpose a jig between each teeth 23 so that each teeth 23 may not deform | transform.

  As mentioned above, although the Example of this invention was described, the effect of this Example is shown below.

  According to the present embodiment, the stator core is composed of an inner core and an outer core, and slots provided in the inner core are formed with substantially the same width from the inner peripheral side to the outer peripheral opening end so that the stator coils are arranged in a line. For this reason, if the diameter of the stator coil cross section and the circumferential width of the slot are made closer, the gap generated between the stator coils can be reduced as much as possible, and the space factor of the stator coil in the slot can be improved. . In addition, since the outer peripheral opening of each slot can be separated in the circumferential direction, it can be prevented from being accidentally inserted into the adjacent slot when the stator coil is wound, and the stator coil can be easily inserted into the slot. Can be wound. Furthermore, since the area of the connection part of the inner core and outer core which are comprised by another member can be enlarged as much as possible, it can prevent that it becomes difficult to flow magnetic flux as much as possible. In addition, the strength of the connection portion of the inner core with the outer core can be improved.

  Further, according to the present embodiment, the outer peripheral end of the teeth provided between the slots is configured to be wider in the circumferential direction than the inner peripheral side, and the inner periphery of the outer core is provided with the teeth. A recess having a narrow width in the circumferential direction with respect to the bottom on the outer peripheral side was formed in the inner peripheral side opening so as to correspond to the shape of the outer peripheral end. For this reason, even if each tooth is sucked to the rotor side, since the circumferential width of the inner circumferential side opening of the recess is smaller than the circumferential width of the outer peripheral end of the tooth, movement of the teeth to the inside is prevented. As much as possible, the magnetic path area can be ensured. Such a configuration is particularly effective when each tooth is provided independently so that a magnetic path is not formed on the inner peripheral side of adjacent teeth.

  Moreover, according to the present Example, the outer peripheral end of each tooth was press-fitted into the recess of the outer core. For this reason, since the clearance gap between a teeth and an outer core is eliminated as much as possible, and a teeth and a recessed part will contact in three surfaces, as much magnetic path area as possible can be ensured. Further, the teeth can be prevented from swinging with respect to the outer core.

  Moreover, according to the present Example, the outer peripheral end surface of each tooth was formed in circular arc shape, and the contact location of the outer peripheral end surface of each tooth in an outer core was also formed in circular arc shape correspondingly. For this reason, since the contact area of the teeth and the outer core can be increased as much as possible, a large magnetic path area can be ensured.

  Moreover, since the stator core of the present embodiment is used for an AC generator, the power generation efficiency is improved.

  In addition, according to this embodiment, since the outer core is composed of a powder magnetic core, a complicated shape can be easily formed, and an insulating coating is applied to the surface of the magnetic powder, so that eddy currents can be generated. It can also be suppressed.

  As mentioned above, although the present Example demonstrated using the alternating current generator for motor vehicles as a rotary electric machine, it is possible to apply not only with a generator but with a motor.

  Further, in this embodiment, the concave portion into which the inner core teeth are inserted is formed on the inner periphery of the outer core, but it is possible to fix them together without the concave portion.

  In this embodiment, the stator coil has a circular cross section, but the cross section may be polygonal. In particular, the space factor of the stator coil in the slot can be improved by making the cross section into a quadrilateral shape.

  Further, in this embodiment, the outer core is formed of a dust core, but it is also possible to form the outer core by a laminated steel plate that is laminated in a state where the surfaces are insulated from each other. In this case, the strength of each part can be improved with respect to the dust core.

  In this embodiment, the inner core and the outer core are fixed by press-fitting, but can be fixed by another method such as welding.

  In this embodiment, the slots are formed radially, but may be provided with a slight inclination in the circumferential direction. At that time, the slot may not be linear but may be curved.

  In the present embodiment, each tooth is configured independently, but each tooth may be connected on the inner peripheral side. In this case, since the inner core is an integral member, manufacturing is facilitated and the movement of each tooth to the inner peripheral side can be prevented, but the thickness is reduced so that the magnetic flux does not easily pass through the connected portion. There is a need.

  In this embodiment, the outer peripheral end surface of each tooth and the outer peripheral side bottom surface of the recess are formed in an arc shape, but may be flat.

  In this embodiment, the original shape of the inner core is assembled to the outer core, and then the final stator is obtained by cutting. However, the inner core is originally composed of a plurality of teeth, and each tooth is assembled to the outer core. It is also possible.

It is side surface sectional drawing of the whole structure of the alternating current generator for motor vehicles as a rotary electric machine. It is a perspective view of the stator of a present Example by which the stator coil was wound. It is a perspective view of the inner core and outer core in the stator of a present Example. It is the figure which expanded the slot part of the stator of a present Example as a cross section. It is the figure which expanded the original form of the inner core of a present Example as a cross section. It is the figure which wound the stator coil to the original form of the inner core of a present Example. It is the figure which fixed the outer core to the original form of the inner core of a present Example.

Explanation of symbols

DESCRIPTION OF SYMBOLS 14 ... Stator core, 14a ... Inner core, 14b ... Outer core, 15 ... Slot, 16 ... Stator coil, 22 ... Stator, 23 ... Teeth, 24 ... Recess, 26 ... Teeth bridge.

Claims (7)

An inner core made of a magnetic body having a plurality of slots opened in the circumferential direction on the outer peripheral side;
An annular outer core disposed on the outer peripheral side of the inner core and forming a magnetic path around the slot;
A stator coil periodically wound in the slot;
A stator of a rotating electric machine having
The slot of the rotating electrical machine is characterized in that the slot is formed to have substantially the same width from the inner peripheral side to the outer peripheral opening end so that the stator coils are arranged in a line. In the stator of the rotating electrical machine according to claim 1,
The outer peripheral end of the teeth provided between the slots is configured to be wider in the circumferential direction with respect to the inner peripheral side,
A rotation characterized in that a recess having a narrow width in the circumferential direction is formed in the inner periphery of the outer rotor so as to correspond to the shape of the outer peripheral end of the teeth. Electric stator. The stator of the rotating electrical machine according to claim 2,
Each of the teeth is provided independently, and the inner core is constituted by a plurality of the teeth. The stator of the rotating electrical machine according to claim 2,
The stator of the rotating electrical machine, wherein an outer peripheral end of each of the teeth is press-fitted into the concave portion of the outer core. In the stator of the rotating electrical machine according to claim 1,
A stator for a rotating electrical machine, wherein an outer peripheral end surface of each tooth is formed in an arc shape, and a contact portion of the outer peripheral end surface of each tooth in the outer core is also formed in an arc shape. An inner core made of a magnetic body having a plurality of slots opened in the circumferential direction on the outer peripheral side;
An annular outer core disposed on the outer peripheral side of the inner core and forming a magnetic path around the slot;
A stator coil periodically wound in the slot;
A stator of a rotating electric machine having
Between the slots, there is provided a substantially sector-shaped tooth whose outer peripheral side is wide from the inner peripheral position to the outer peripheral end of the mounting position of the stator coil, and the circumferential width of the slot is the width of one stator coil. A stator for a rotating electrical machine, wherein the stator is larger than a width and smaller than a width of two stator coils. A drive shaft that is rotationally driven by a drive source;
A plurality of different magnetic poles are alternately formed in the circumferential direction, and a rotor that rotates integrally with the drive shaft;
An inner core made of a magnetic material having a plurality of slots opened in the circumferential direction in the circumferential direction, an outer core disposed on the outer circumferential side of the inner core and forming a magnetic path around the slot, and periodically in the slots A stator having a wound stator coil;
An alternator having
2. The AC generator according to claim 1, wherein the slot is formed so that the width of the stator coils is aligned in a line from the inner peripheral side to the outer peripheral opening end.

Images