JP7092477B2 - Rotating electric stator - Google Patents

Description

The present invention relates to a rotary electric machine stator, and more particularly to a structure for reinforcing a stator core.

According to Patent Document 1, in a rotary electric stator, a ring-shaped non-magnetic material is formed on the axial end surface of the tip portion on the inner peripheral side of the arrangement range of the coil wound around the teeth in each of the plurality of teeth. A configuration for fixing the reinforcing member is disclosed. According to this configuration, it is described that in the rotary electric machine stator, the rigidity of the teeth can be improved without depositing foreign substances which may cause deterioration of the electrical insulation performance in the slots formed between the teeth. ..

Japanese Unexamined Patent Publication No. 2017-41982

The rotary electric stator described in Patent Document 1 prevents foreign matter from entering the slot and prevents the coil from coming off, but cannot reinforce the stator core or increase the fixing force of the coil.

An object of the present invention is to provide a rotary electric stator which can increase the annular rigidity of the stator by utilizing the thermal expansion of the non-magnetic material ring, and as a result, can also improve the vibration noise performance.

The rotary electric stator according to the present invention includes an annular yoke, a stator core having a plurality of teeth protruding inward in the stator radial direction from the yoke at positions spaced apart from each other in the circumferential direction of the stator, and the stator core. A coil wound around the teeth and having a coil end portion protruding outward in the stator axial direction from the teeth, and a non-magnetic ring provided on the outer side in the stator axis direction of the stator core and inside in the stator radial direction of each tooth. The non-magnetic material ring is provided with a circumferential direction in at least one of the inner ends in the stator radial direction of the teeth adjacent to each other in the circumferential direction of the stator and the coil end portions adjacent to each other in the circumferential direction of the stator. A protrusion that fits in contact with each other is formed on both sides.

According to this configuration, the protrusions fitted in contact between the teeth and the coil ends are thermally expanded, so that the teeth are pressed in the circumferential direction directly or through the coil ends. As a result, each tooth is firmly connected in an annular shape via the protrusion of the non-magnetic material ring. As a result, the annular rigidity of the rotary electric machine stator is increased, and the vibration noise performance of the rotary electric machine stator is improved.

In the rotary electric machine stator according to the present invention, the protrusion may be formed so as to project in the stator axial direction in the non-magnetic material ring, and may be fitted in contact with the teeth portion adjacent to each other in the circumferential direction of the stator. ..

According to this configuration, the protrusions fitted between the teeth in a contact state thermally expand, so that the teeth are directly pressed in the circumferential direction. As a result, the teeth are firmly connected in an annular shape via the non-magnetic material ring. As a result, the annular rigidity of the rotary electric machine stator is increased, and the vibration noise performance of the rotary electric machine stator is improved.

Further, in the rotary electric machine stator according to the present invention, the protrusion is formed so as to project radially outward in the non-magnetic material ring, and is fitted in contact with the coil end portions adjacent to each other in the circumferential direction. May be good.

According to this configuration, the protrusions fitted between the coil ends in contact state thermally expand, so that the teeth are pressed in the circumferential direction through the coil ends. As a result, the teeth are firmly connected in an annular shape via the non-magnetic material ring. As a result, the annular rigidity of the rotary electric machine stator is increased, and the vibration noise performance of the rotary electric machine stator is improved.

Further, in the rotary electric machine stator according to the present invention, the protrusion may be press-fitted into at least one of the inner end portion in the stator radial direction of the tooth and the coil end portion.

According to this configuration, the non-magnetic material ring can be more firmly assembled to the stator core by press-fitting the protrusions between the teeth and the like.

According to the rotary electric stator according to the present invention, the teeth are pressed in the circumferential direction directly or through the coil end portion by the thermal expansion of the protrusions fitted between the teeth and the coil ends in a contact state. To. As a result, the teeth are firmly connected in an annular shape via the non-magnetic material ring. As a result, the annular rigidity of the rotary electric machine stator is increased, and the vibration noise performance of the rotary electric machine stator is improved.

It is sectional drawing in the axial direction of the rotary electric machine including the rotary electric machine stator which is one Embodiment of this invention. It is a perspective view of the rotary electric machine stator shown in FIG. It is a perspective view which shows the non-magnetic material ring attached to the rotary electric machine stator shown in FIG. It is a perspective view of the rotary electric machine stator which is another embodiment of this invention. It is a perspective view which shows the non-magnetic material ring attached to the rotary electric machine stator shown in FIG. FIG. 5 is a perspective view showing a modified example of the non-magnetic material ring of FIG. 5, and an enlarged view of a protrusion thereof.

Hereinafter, embodiments according to the present invention will be described in detail with reference to the drawings. Hereinafter, the stator used for the rotary electric machine mounted on the vehicle will be described, but this is an example for explanation and may be used for purposes other than mounting on the vehicle. In the following, a coil wound in a single layer using a flat wire will be described as the coil, but this is an example for explanation, and a round wire having a circular cross section other than the flat wire, a winding having an elliptical cross section, or the like may be used. .. Further, it may be a multi-layer winding. The winding method may be concentrated winding or distributed winding. In the following, the non-magnetic material ring will be described as being provided on both end faces in the axial direction of the tooth, but a non-magnetic material ring as a reinforcing member may be provided only on one end face of both end faces in the axial direction of the tooth. ..

FIG. 1 is an axial sectional view of a rotary electric machine 10 including a rotary electric machine stator 14A according to an embodiment of the present invention. In the following, the rotary electric stator is appropriately referred to as a stator. The rotary electric machine 10 is a motor generator that functions as an electric motor when the vehicle runs by power under the control of a drive circuit and as a generator when the vehicle is braking, and is a three-phase synchronous rotary electric machine.

The rotary electric machine 10 is housed in the case 16. The case 16 is a housing made of a metal such as an aluminum alloy. The case 16 is composed of a bottomed cylindrical accommodating member 18 and a lid member 20 that closes the opening of the accommodating member 18. The lid member 20 is fastened and fixed to the accommodating member 18 by bolts 22.

The rotary electric machine 10 is composed of a rotor 12 and a stator 14A arranged on the radial outer side of the rotor 12 with a predetermined gap. The rotor 12 includes a cylindrical rotor core 24 and a shaft 26 fixed to the rotor core 24. The rotor core 24 is, for example, a magnetic component formed by laminating and connecting magnetic thin plates punched in an annular shape in the axial direction. A plurality of permanent magnets (not shown) are embedded in the vicinity of the outer peripheral surface of the rotor core 24 at intervals in the circumferential direction. Further, the rotor core 24 is fixed to the outer periphery of the shaft 26 by, for example, shrink fitting or the like.

The shaft 26 of the rotor 12 is rotatably supported by a bearing member 19 having one end in the axial direction fixed to the bottom 18a of the accommodating member 18 of the case 16. On the other hand, the other end of the shaft 26 in the axial direction is rotatably supported by the bearing member 21 fixed to the lid member 20 of the case 16.

FIG. 2 is a perspective view of the stator 14A shown in FIG. In FIG. 2 (also in FIG. 4), the circumferential direction of the stator, the radial direction of the stator, and the axial direction of the stator are indicated by arrows. In the following, the circumferential direction of the stator is simply referred to as the circumferential direction, the radial direction of the stator is simply referred to as the radial direction, and the axial direction of the stator is simply referred to as the axial direction.

As shown in FIGS. 1 and 2, the stator 14A includes a stator core 28, a coil 30 mounted on the stator core 28, and a non-magnetic ring 32.

The stator core 28 is, for example, a magnetic component formed by laminating and connecting magnetic thin plates punched in an annular shape in the axial direction. The stator core 28 has an annular yoke 34 and a plurality of teeth 36 protruding radially inward from the yoke 34 at positions spaced apart in the circumferential direction in the yoke 34. The stator core 28 may be formed by integrally molding magnetic powder into a predetermined shape instead of a laminated body of magnetic thin plates.

A plurality of (three in this embodiment) mounting portions 38 are formed on the outer peripheral surface of the stator core 28 so as to bulge outward in the radial direction. A bolt hole 40 is formed in the mounting portion 38 so as to penetrate in the axial direction. As shown in FIG. 1, the bolt 42 inserted into the bolt hole 40 of the mounting portion 38 is screwed into the female screw hole of the bottom portion 18a of the accommodating member 18 of the case 16. As a result, the stator 14A including the stator core 28 is fixed in the case 16.

Slots 44 are formed between the teeth 36 adjacent to each other in the circumferential direction. The number of slots 44 is the same as that of the teeth 36 (15 in this embodiment). Further, the slot 44 is a space or a groove that opens inward in the radial direction and opens at both ends in the axial direction.

The coil 30 is a winding coil that uses a conducting wire with an insulating film and is wound around the teeth 36 by a predetermined number of turns by passing the conducting wire through the slot 44 by a predetermined winding method. The coil 30 may be a single-layer winding concentrated winding coil, a multi-layer winding concentrated winding coil, or a distributed winding coil.

As the wire of the lead wire with an insulating film of the coil 30, a copper wire, a copper-tin alloy wire, a silver-plated copper-tin alloy wire, or the like can be used. As the strand, a flat wire having a substantially rectangular cross-sectional shape is used. As the insulating film, a polyamide-imide enamel film is used. Instead of this, polyesterimide, polyimide, polyester, formal and the like can be used.

The coil 30 has a coil end portion 31 projecting outward in the axial direction from the end faces on both sides in the axial direction of the teeth 36. In the present embodiment, since the coil 30 is wound around each tooth 36 in a concentrated winding manner, a gap 33 is formed between the coil end portions 31 adjacent to each other in the circumferential direction.

The non-magnetic material ring 32 is a member used to press the teeth 36 in the circumferential direction to increase the annular rigidity of the stator 14A. The non-magnetic ring 32 also has a function of preventing the coil 30 from coming out from the teeth 36 inward in the radial direction.

FIG. 3 is a perspective view showing a non-magnetic material ring 32 assembled to the stator 14A shown in FIG. As shown in FIGS. 2 and 3, the non-magnetic ring 32 has an annular portion 32a formed in a ring shape and a plurality of protrusions 32b protruding in the axial direction from the annular portion 32a. The protrusions 32b are portions of the stator core 28 that are fitted between the teeth 36 adjacent to each other in the circumferential direction, and are provided in the same number (15 in the present embodiment) at the same circumferential spacing as the teeth 36.

The annular portion 32a of the non-magnetic material ring 32 is formed in a straight line portion at a position corresponding to the teeth 36 of the stator core 28 when viewed from the axial direction, and is formed in a polygonal shape in which such straight line portions are continuous as a whole. There is. However, the present invention is not limited to this, and the annular portion 32a may be formed in an annular shape.

The protrusion 32b of the non-magnetic ring 32 protrudes from the annular portion 32a in the shape of a rectangular plate, and its radial thickness is formed to be the same as that of the annular portion 32a. Further, the protrusion 32b is provided at a position facing the corner of the annular portion 32a, and is formed by being bent in a substantially V shape when viewed from the axial direction.

Referring to FIGS. 1 and 2, the non-magnetic ring 32 is installed on the axial end surface of the stator core 28 so as to face the radial inner tip of each tooth 36. At this time, the protrusion 32b of the non-magnetic material ring 32 is fitted between the teeth 36 adjacent to each other in the circumferential direction. The protrusions 32b are arranged in contact with the radial inner tip portions of the teeth 36 on both sides in the circumferential direction. Further, when the non-magnetic material ring 32 is assembled to the stator core 28 from the axial direction, the protrusion 32b may be press-fitted between the teeth 36 adjacent to each other in the circumferential direction. The non-magnetic ring 32 is preferably set on both sides of the stator core 28 in the axial direction. Further, it is preferable that the non-magnetic material ring 32 is firmly fixed by the stator core 28 using an adhesive.

For the non-magnetic material ring 32, it is preferable to use a resin from the viewpoint of moldability, strength and the like. As the resin, a material having electrical insulation and having appropriate strength and heat resistance is used. For example, epoxy resin, polyimide resin, aromatic nylon resin compound and the like are used. The resin may contain a suitable filler. When the non-magnetic material ring 32 is formed of, for example, an epoxy resin in this way, the coefficient of linear expansion of the epoxy resin is 62.0 (× 10 ^-6 / ° C.), and the linear expansion of the stator core 28 made of a thin magnetic material plate. The coefficient is larger than 16.8 (× 10 ^-6 / ° C).

Generally, in a stator of a rotary electric machine, each tooth of the stator core has a structure in which the stator yoke side is a support end and the tip portion on the inner side in the radial direction is a free end. It may vibrate due to the mass of the coil, etc., and noise may be generated. On the other hand, in the stator 14A of the rotary electric machine 10 in the present embodiment, when the temperature of the stator 14A rises due to the operation of the rotary electric machine 10, the temperature of the non-magnetic material ring 32 also rises and thermally expands. Since the linear expansion coefficient of the non-magnetic material ring 32 is larger than that of the stator core 28, the protrusion 32b of the non-magnetic material ring 32 thermally expands, so that the teeth 36 located in contact with both sides in the circumferential direction are radially inside. The tip will be pressed in the circumferential direction. As a result, the radial inner tip portions of the teeth 36 are firmly connected via the non-magnetic material ring 32. As a result, the annular rigidity of the stator 14A is increased, and the vibration noise performance can be improved.

Next, the stator 14B, which is another embodiment of the present invention, will be described with reference to FIGS. 4 and 5. FIG. 4 is a perspective view of the stator 14B, and FIG. 5 is a perspective view showing a non-magnetic material ring 32 assembled to the stator 14B shown in FIG. Hereinafter, the same configuration as that of the rotary electric machine 10 described above will be referred to with the same reference numerals and the description thereof will be omitted.

As shown in FIGS. 4 and 5, the non-magnetic ring 32 used for the stator 14B has an annular portion 32a formed in a ring shape and a plurality of protrusions 32c protruding radially outward from the annular portion 32a. Have. The protrusions 32c are portions of the stator core 28 that are fitted into the gaps 33 between the coil end portions 31 adjacent to each other in the circumferential direction, and are provided in the same number as the teeth 36 at the same circumferential spacing (15 in this embodiment). ing.

The protrusion 32c of the non-magnetic ring 32 has a rectangular parallelepiped shape and is formed in a rectangular shape when viewed from the axial direction. That is, the protrusion 32c has the same circumferential width between the base end portion on the annular portion 32a side and the tip end portion. Further, the thickness of the protrusion 32c in the axial direction is the same as that of the annular portion 32a. The configuration of the stator 14B other than the non-magnetic ring 32 is the same as that of the stator 14A described above.

As shown in FIG. 4, in the stator 14B, the non-magnetic material ring 32 is installed on the axial end surface of the stator core 28 so as to face the radial inner tip of each tooth 36. At this time, the protruding portion 32c of the non-magnetic material ring 32 is fitted in the gap 33 between the coil end portions 31 adjacent to each other in the circumferential direction. The protrusion 32c is arranged in a state of being in contact with the radial inner tip portion of the coil end portion 31 on both sides in the circumferential direction. Further, when the non-magnetic material ring 32 is assembled to the stator core 28 from the axial direction, the protrusion 32c may be press-fitted between the coil end portions 31 adjacent to each other in the circumferential direction.

In the stator 14B to which such a non-magnetic material ring 32 is mounted, when the temperature of the stator 14B rises due to the operation of the rotary electric machine 10, the temperature of the non-magnetic material ring 32 also rises and thermally expands. Since the coefficient of linear expansion of the non-magnetic material ring 32 is larger than that of the stator core 28, the protrusion 32b of the non-magnetic material ring 32 thermally expands, so that the coil end portion 31 is located in contact with each other on both sides in the circumferential direction. The radial inner tip of each tooth 36 is pressed in the circumferential direction. As a result, the radial inner tip portions of the teeth 36 are firmly connected via the non-magnetic material ring 32. As a result, the annular rigidity of the stator 14B is increased, and the vibration noise performance can be improved.

FIG. 6 is a perspective view showing a modified example of the non-magnetic material ring 32 of FIG. 5, and an enlarged view of the protrusion 32d thereof. The non-magnetic ring 32 of this modification has an annular portion 32a formed in a ring shape and a plurality of protrusions 32d protruding radially outward from the annular portion 32a. The protrusions 32d are portions of the stator core 28 that are fitted into the gaps 33 between the coil end portions 31 adjacent to each other in the circumferential direction, and are provided in the same number as the teeth 36 at the same circumferential spacing (15 in this embodiment). ing.

The protrusion 32d of the non-magnetic material ring 32 is formed in a trapezoidal shape when viewed from the axial direction, and the thickness in the axial direction is the same as that of the annular portion 32a. In the protrusion 32d, when the circumferential width of the base end portion on the annular portion 32a side is L1 and the circumferential width of the tip portion is L2, the circumferential width L1 of the tip portion is the circumference of the gap 33 between the coil end portions 31. It is smaller than the directional width L3 (see FIG. 4), and the circumferential width L2 of the base end portion is larger than the circumferential width L3 of the gap 33. By forming the protrusion 32d in this way, the protrusion 32d can be easily fitted or press-fitted into the gap 33 between the coil end portions 31, and there is an advantage that the non-magnetic ring 32 can be easily assembled to the stator core 28. be. Further, the stator using the non-magnetic material ring 32 of this modification can also obtain the same effect as the above-mentioned stators 14A and 14B.

The rotary electric stator according to the present invention is not limited to the above-described embodiment and its modifications, and various changes and improvements can be made.

For example, in the above, the case where the non-magnetic material ring 32 is provided with a protrusion 32b that is fitted between the teeth 36 adjacent to each other in the circumferential direction as shown in FIGS. 2 and 3, and shown in FIGS. 4 to 5. As described above, the case where the protrusions 32c and 32d that fit into the gap 33 between the coil end portions 31 adjacent to each other in the circumferential direction is provided has been described, but the present invention is not limited thereto. The non-magnetic material may include both of these protrusions.

10 rotary electric machine, 12 rotor, 14A, 14B rotary electric machine stator, 16 case, 18 accommodating member, 18a bottom, 19, 21 bearing member, 20 lid member, 22, 42 bolt, 24 rotor core, 26 shaft, 28 stator core, 30 coil , 31 coil end, 32 non-magnetic ring, 32a annular part, 32b, 32c, 32d protrusion, 33 gap, 34 yoke, 36 teeth, 38 mounting part, 40 volt hole, 44 slot, L1, L2, L3 circumference Direction width.

Claims (4)

An annular yoke and a stator core having a plurality of teeth protruding inward in the stator radial direction from the yoke at positions spaced apart from each other in the circumferential direction of the stator.
A coil having a coil end portion wound around the tooth of the stator core and protruding outward in the stator axial direction from the tooth, and a coil having a coil end portion.
A non-magnetic ring provided on the outside in the stator axial direction of the stator core and inside in the stator radial direction of each tooth and having a coefficient of linear expansion larger than the coefficient of linear expansion of the stator core is provided.
The non-magnetic material ring is formed with protrusions that are fitted in contact with the coil end portions on both sides in the circumferential direction between the coil end portions adjacent to each other in the circumferential direction of the stator.
By thermally expanding the protrusion, the radial inner tip portion of the tooth is pressed in the circumferential direction through the coil end portion located in contact with both sides in the circumferential direction.
Rotary electric stator. In the rotary electric motor stator according to claim 1,
The protrusion is formed in the non-magnetic material ring so as to project in the stator axial direction, and is fitted in contact with the teeth portion adjacent to each other in the circumferential direction of the stator. In the rotary electric stator according to claim 1 or 2,
The protrusion is formed in the non-magnetic material ring so as to project outward in the radial direction, and is fitted in a state of being in contact with the coil end portions adjacent to each other in the circumferential direction. In the rotary electric stator according to any one of claims 1 to 3,
The rotary electric stator whose protrusion is press-fitted into at least one of the inner end portion of the tooth in the radial direction and the coil end portion.

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