JP2010226815A - Motor stator, split stator and manufacturing method thereof - Google Patents

Abstract

A motor stator is effectively cooled.
[Solution]
A plurality of divided stators 20 are circumferentially arranged to constitute a motor stator. Each split stator 20 includes a back yoke portion 3a on the outer peripheral side, a tooth portion 3b extending in the center direction from the peripheral core portion, and a coil 2 wound around the tooth portion. When the divided stators 20 are arranged circumferentially, slits 31 are formed between the peripheral cores 3a of the respective divided stators 20, and the wedges extend radially inward from the slits 31 and are positioned between adjacent coils. A heat conducting fin 5 of the shape is provided.
[Selection] Figure 4

Description

  The present invention relates to a motor stator and a divided stator formed by arranging a plurality of divided stators circumferentially.

  Various types of motors have been widely used in the past, but especially in small-sized and high-power motors, the coil temperature rise due to copper loss heat generation in the coil due to the increase in the amount of current becomes a problem at high loads and low rotation speeds. Become. For example, the upper limit of the operating temperature exists in the motor due to the heat resistant temperature of the enamel used as the insulating coating material of the coil, and the operating temperature must be lower than that. Therefore, the driving range of the motor is limited so that the operating temperature is equal to or lower than the upper limit temperature, or the motor is increased in size to suppress an increase in operating temperature. However, with such a technique, it is difficult to obtain a small and high output motor.

  For this reason, a means for suppressing the temperature rise by providing a cooling mechanism is also employed. Patent Document 1 has a stator support member that holds both axial end portions of a split stator. The stator support member is made of a good heat conductive material to promote heat dissipation, and a cooling flow is generated in the stator support member. It is shown that a path is provided.

  Patent Document 2 discloses a configuration in which a flow path through which oil flows is provided inside the stator to cool the stator.

  Patent Document 3 discloses a configuration in which a cooling passage is formed in a slot in which a stator coil is disposed.

JP 2001-359256 A JP 2004-320974 A JP 2002-186205 A

  However, in Patent Document 1, it is difficult to cool the central portion of the core and the coil of that portion. Also in Patent Document 2, it is difficult to effectively cool the entire stator, and it is difficult to effectively cool the entire coil. Moreover, in patent document 3, there existed a problem that it was difficult to circulate the oil which is a refrigerant | coolant uniformly, and it was difficult to cool effectively as a whole.

  The present invention is a motor stator formed by arranging a plurality of divided stators in a circumferential shape and accommodating them in a fastening ring, each divided stator comprising an outer peripheral peripheral core portion (back yoke portion), Including a tooth portion extending in the center direction from the peripheral core portion and a coil wound around the tooth portion, and when the divided stator is arranged in a circumferential shape, a slit is formed between the peripheral cores of the respective divided stators. A wedge-shaped heat conducting fin is provided that extends inward in the radial direction from the slit and is positioned between adjacent coils on the front end side.

  Further, it is preferable that the heat conducting fin is inserted from the outside through a slit provided in the fastening ring.

  In addition, it is preferable that the heat conductive fin is formed of a metal having good heat conductivity.

  In addition, it is preferable that an outer end portion of the heat conducting fin protrudes outward from the fastening ring, and the protruding portion contacts the refrigerant and functions as a cooling fin.

  In addition, it is preferable that an insulating coating is formed on a surface of the heat transfer fin that is in contact with the coil.

  Further, the present invention is a method of manufacturing a motor stator in which a plurality of divided stators are arranged circumferentially and accommodated in a fastening ring, and each divided stator includes an outer peripheral peripheral core portion, Including a teeth portion extending in the center direction from the peripheral core portion and a coil wound around the teeth portion, and when the divided stator is arranged in a circumferential shape, a slit is formed between the peripheral cores of each divided stator, A wedge-shaped heat conduction fin is inserted inward in the radial direction from the slit so that the tip side is located between adjacent coils.

  According to the present invention, the heat transfer fin formed from the heat good conductor is brought into contact with the coil, whereby the coil can effectively dissipate heat through the heat transfer fin. In particular, the heat transfer fins are relatively easy to manufacture because they are inserted between the coils through slots formed between the split cores.

It is a figure which shows a structure with the division | segmentation core part 3. FIG. It is a figure which shows the state of the slit 31 at the time of connecting two division | segmentation core parts 3. FIG. It is a figure which shows the structural example of the heat-transfer fin part. It is a figure which shows the structure of the division | segmentation stator 20 which wound the coil 2 around the division | segmentation core part 3. FIG. It is a figure which shows the top view of the insulator 4. FIG. It is a figure showing the state where a plurality of division stators 20 are arranged. FIG. 2 is a diagram illustrating a configuration of a fastening ring 1. It is a figure which shows the state which carried out the shrink fit of the some division | segmentation stator 20 in the fastening ring 1. FIG. It is a figure which shows the structure at the time of accommodating the heat-transfer fin part 5 inside the fastening ring 1. FIG. It is a figure which shows the structure at the time of extending a part of heat-transfer fin part 5 from the slit of the fastening ring 1 to the outer side. It is a figure which shows the structure at the time of extending a part of heat-transfer fin part 5 from the slit of the fastening ring 1 to the outer side, and making the part into a cooling fin. It is a figure which shows the state which formed the refrigerant | coolant flow path 7 between the fastening ring 1 and the case 6. FIG. It is a figure which shows the state which sealed the refrigerant flow path 7 with O ring. It is a figure which shows the structural example of the slit formed with an adjacent division | segmentation core. It is a figure which shows the example of the shape of the slit formed in the fastening ring.

  Hereinafter, embodiments of the present invention will be described with reference to the drawings.

  FIG. 1 is a plan view of a portion of the split core portion 3 of the split stator as viewed from the axial direction. The split core portion 3 includes a back yoke portion (peripheral core portion) 3a that is arranged on the outer side in a circumferential shape, and a teeth portion 3b that extends inward from the center portion of the back yoke portion 3a.

  Here, as shown in FIG. 2, a convex portion 311 is formed at the upper and lower ends and a concave portion 312 is formed at the central portion on the side portion of the back yoke portion 3a that contacts the adjacent divided stator. The concave portion 312 is connected by the back yoke portion 3a to form the slit 31.

  And the plate-shaped heat-transfer fin 5 shown by FIG. 3 is inserted in this slit 31 from the outer side. In FIG. 2A, the heat transfer fin 5 has a wedge shape and is pushed into the slit 31. On the other hand, the heat transfer fin 5 of FIG. 2 (B) has a collar 51 on one end side, and the collar 51 is divided into cores by inserting the heat transfer fin 5 into the slit 31 from the side where the collar 51 does not exist. The heat transfer fin 5 is inserted outside the portion 3. Note that a donut-shaped stator core is formed by arranging a predetermined number of divided core portions 3 in a circumferential shape.

  And as shown in FIG. 4, the coil 2 is wound around the teeth part 3b of the division | segmentation core part 3 via the insulator mentioned later, and the division | segmentation stator 20 is comprised. In FIG. 4, the insulator is omitted. The coil 2 is a thin plate-like copper flat conductive wire, and is a coil extending in the radial direction formed by winding it around the teeth portion 3b a plurality of times. In this example, the end surface (inner peripheral side end surface) on the center side in the radial direction of the coil 2 forms substantially the same surface as the end surface (inner peripheral side end surface) on the center side of the tooth portion 3b. The tooth portion 3b is a trapezoidal shape in which the cross-sectional area decreases toward the inside, and the shape of the tooth portion 3b is a prismatic shape from the periphery of the stator toward the center. The coil 2 is disposed around the tooth 3b via an insulator 4. It is wound.

  Since the coil 2 is a single winding of a flat conductive wire and its width itself is constant, the outer end of the coil 2 gradually tapers toward the center side as in the outer periphery of the tooth portion 3b. In this example, the end surface on the stator center side of the coil 2 and the end surface of the tooth portion 3b are substantially the same surface, but it is not always necessary to form the same surface. However, in order to accommodate the coil 2 as efficiently as possible, it is preferable that the surface on the center side of the coil 2 and the surface on the center side of the tooth portion 3b are substantially the same surface.

  The heat transfer fin portion 5 extends to the inner peripheral side surface of the coil 2 and may have a certain size on the inner peripheral side. However, the heat transfer fin portion 5 contacts the side surface of the coil 2 as much as possible, and unnecessary magnetic flux leakage. In order to prevent the occurrence of the occurrence, it is better that the outer circumferential side of the coil 2 is in direct contact with the adjacent coil 2 at a certain portion inside the radial direction.

  In the present embodiment, the split core portion 3 is formed by laminating electromagnetic steel plates, and the heat transfer fin portion 5 is formed of a material having good thermal conductivity such as aluminum or copper. Thus, the heat generated in the coil 2 can be effectively conducted by using a material having good heat conduction. And by comprising the heat-transfer fin part 5 by a nonmagnetic material, it can prevent that a magnetic flux leaks from the division | segmentation core part 3 to the heat-transfer fin part 5, and the magnetic flux which generate | occur | produces by the coil 2 is sent from the teeth part 3b to a rotor. It can work effectively.

  Here, as described above, the synthetic resin insulator 4 is disposed between the periphery of the tooth portion 3 b and the inner peripheral side of the coil 2. FIG. 5 shows a plan view of the insulator 4, and FIG. 6 also shows a part of the insulator 4 as viewed from the inside. The insulator 4 has a portion 4a that covers the side surface of the tooth portion 3b, portions 4c and 4d that are disposed on the upper and lower portions of the tooth portion 3b, and a portion 4b that is along the inner peripheral surface of the back yoke portion 3a. As a result, the coil 2 is isolated from the tooth portion 3b and the back yoke portion 3a. Furthermore, a part of the insulator 4 is arranged on the upper part of the coil 2, and this constitutes a part 4 e that supports a connection wiring with a peripheral circuit of the coil 2. The tip of the portion 4a that covers the teeth side surface of the insulator 4 has a flange that slightly expands in the circumferential direction, and holds the end surface on the inner peripheral side of the coil 2.

  FIG. 6 shows a state in which three divided stators 20 are arranged circumferentially. One divided stator 20 describes the divided core portion 3, the coil 2, and the insulator 4, and one divided stator 20 is a divided core. The part 3 and the insulator 4 are described, and the other split stator describes only the split core part 3.

  Here, when forming a motor stator, first, the insulator 4 is arranged on the divided core portion 3 of the divided stator 20. Next, the coil 2 is fitted into the insulator 4. Then, the divided stators 20 formed in this way are arranged circumferentially. Then, the obtained divided stator 20 having the circumferential shape into which the heat transfer fins 5 are inserted is shrink-fitted into the fastening ring 1. That is, the circumferentially arranged divided stators are accommodated in the heated fastening ring 1 and tightened at a reduced temperature.

  FIG. 7 shows a configuration example of the fastening ring 1, and FIG. 8 shows a state in which the divided stator is accommodated. Thus, the slit 11 is provided in the fastening ring 1 of this embodiment. In this case, the heat transfer fins 5 are inserted between the adjacent coils 2 through the slits 11 provided from the outside of the fastening ring 1 and through the slits 31 provided in the split core portion 3. When the relative positions of the slits 11 and 31 fluctuate during the cooling contraction of the fastening core 1, it becomes difficult to insert the heat transfer fin portion 5 thereafter. Therefore, the heat transfer fin portion 5 is inserted before cooling. It is preferable. Alternatively, the heat transfer fin portion 5 may be inserted before cooling and may be inserted after cooling.

  9 to 11 show configuration examples of the heat transfer fins 5 inserted from the outside of the fastening ring 1.

  In FIG. 9, the heat transfer fin 5 has no collar as shown in FIG. 2A, and is pushed into the slit 31, and the fastening ring 1 exists on the outside thereof. Further, the case 6 is concentrically located outside the fastening ring 1 and the upper and lower sides of the fastening ring 1 and the case 6 are closed, so that a sealed refrigerant flow path 7 is formed here. As the refrigerant, it is preferable to use water or oil such as ATF (automatic transmission fluid).

  In FIG. 10, the heat transfer fin 5 has a collar as shown in FIG. 2B, and the collar 51 is located in the refrigerant flow path 7 outside the fastening ring 1. In addition, when using water, it is necessary to seal the slit 11 so that water may not enter the inside from the slit 11. On the other hand, if oil is used, there is not much need for sealing.

  In FIG. 11, the part located in the refrigerant flow path 7 of the heat transfer fin 5 is uneven, and the recessed part is a refrigerant flow path. Therefore, the part located in the refrigerant flow path 7 of the heat transfer fin 5 functions as the cooling fin 52, and heat exchange between the heat transfer fin 5 and the refrigerant can be performed more efficiently.

  FIG. 12 is a plan view of the example shown in FIG. Thus, the case 6 is disposed concentrically outside the fastening ring 1, and the refrigerant flow path 7 is formed between the case 6 and the fastening ring 1. As shown in the drawing, the refrigerant flow path 7 can be formed as a spiral flow path or a plurality of parallel flow paths by means of ridges or partition ridges provided on the surface of the case 6 or the fastening ring 1. Further, as shown in FIG. 12, the upper and lower sides of the refrigerant flow path 7 may be sealed by O-rings 14. The case 6 may be provided with an inflow pipe and an outflow pipe for the refrigerant so that the refrigerant flows through the refrigerant flow path 7.

  Thus, in the motor stator according to the present embodiment, the outer periphery of the coil 2 in one divided stator 20 is in direct contact with the heat transfer fin 5. For this reason, the heat generated in the coil 2 is easily transmitted to the heat transfer fins. The heat transfer fins 5 are also present between the split core portions 3 and have a wedge shape extending to the fastening ring 1. Therefore, the heat generated in the coil 2 is easily transmitted to the fastening ring 1 through the heat transfer fins 5. And since the refrigerant | coolant has distribute | circulated the outer side of the fastening ring 1, heat can be effectively dissipated to the refrigerant | coolant. Therefore, even if the amount of heat generated by the coil 2 is large, the temperature rise can be suppressed and a high output motor can be obtained. In addition, the heat transfer fin 5 has a wedge shape, and the volume of the portion that transfers more heat of the coil 2 is larger, so that effective heat transfer is achieved. Furthermore, more suitable heat dissipation is achieved by positioning a part of the heat transfer fin portion 5 in the refrigerant passage 7.

  In addition, by configuring the heat transfer fin portion 5 with a non-magnetic material, it is possible to eliminate the influence on the flow of magnetic lines of force due to the heat transfer fin portion 5 and achieve a suitable motor drive.

  FIG. 14 shows another configuration example of the split core unit 3. In this example, no convex portion is formed at the upper end of the split core portion 3, and the upper end of the slit 31 is open. Therefore, in this example, the heat transfer fin portion 5 can be inserted into the slit 31 and between the coils 2 from above, and then the fastening ring 1 can be shrink-fitted.

  Furthermore, as shown in FIG. 15, it is also preferable to form a groove 101 that accommodates the outer end of the heat transfer fin portion 5 in the fastening ring 1. As a result, the heat transfer fin portion 5 can be inserted from above by being matched with the groove 101 and the slit 31.

  DESCRIPTION OF SYMBOLS 1 Fastening ring, 2 coils, 3 division | segmentation core part, 3a back yoke part, 3b teeth part, 4 insulator, 5 heat-transfer fin part, 6 case, 7 refrigerant | coolant flow path, 14 O ring, 20 division | segmentation stator.

Claims (6)

A motor stator in which a plurality of divided stators are arranged in a circumferential shape and accommodated in a fastening ring,
Each split stator
Including a peripheral core portion on the outer peripheral side, a teeth portion extending in the center direction from the peripheral core portion, and a coil wound around the teeth portion;
When the divided stators are arranged circumferentially, slits are formed between the peripheral cores of the divided stators, extending from the slits radially inward, and having a wedge-shaped heat conduction located between adjacent coils. A motor stator provided with fins. In the motor stator according to claim 1,
The motor stator, wherein the heat conducting fin is inserted from the outside through a slit provided in the fastening ring. The motor stator according to claim 1 or 2,
The motor stator, wherein the heat conductive fin is formed of a metal having good heat conductivity. In the motor stator according to any one of claims 1 to 3,
The motor stator, wherein an outer end portion of the heat conducting fin protrudes outward from the fastening ring, and the protruding portion contacts a refrigerant and functions as a cooling fin. In the motor stator according to any one of claims 1 to 4,
A motor stator, wherein an insulating coating is formed on a surface of the heat transfer fin that is in contact with the coil. A method of manufacturing a motor stator in which a plurality of divided stators are arranged circumferentially and accommodated in a fastening ring.
Each split stator
Including a peripheral core portion on the outer peripheral side, a teeth portion extending in the center direction from the peripheral core portion, and a coil wound around the teeth portion;
When the divided stators are arranged circumferentially, slits are formed between the peripheral cores of the respective divided stators, and wedge-shaped heat conduction fins are positioned between the adjacent coils on the tip side toward the inside in the radial direction from the slits. A motor stator manufacturing method, wherein the motor stator is inserted as described above.