JP2019022368A - Stator core - Google Patents

Abstract

To provide a stator core which is inexpensive, has a simple structure, and achieves high cooling performance.SOLUTION: A stator core 10 is formed by laminating multiple steel plates 11. On an outer peripheral surface 15 of the stator core 10, a refrigerant storage part S which stores a refrigerant is formed at an area including an axial center part of the stator core 10.SELECTED DRAWING: Figure 1

Description

  The present invention relates to a stator core that can be efficiently cooled.

  A stator of a rotating electrical machine is configured by winding a winding around a stator core. The temperature of the stator rises due to heat generated by copper loss or eddy current loss when the rotating electrical machine operates. For this reason, a method is known in which a coolant such as cooling oil is dropped from the coolant supply pipe onto the outer peripheral surface of the stator core to cool the stator core. In the cooling method by dripping the refrigerant, the refrigerant flows down immediately along the outer peripheral surface of the stator core, so that the refrigerant does not spread evenly. In some cases, a sufficient cooling effect could not be obtained at the center. Patent Document 1 discloses a liquid cooling motor in which a large number of silicon steel plates provided with notches on the outer periphery are stacked and the notches are continuous in the circumferential direction to form a spiral refrigerant passage. .

JP 7-264810 A

  However, according to the liquid-cooled motor described in Patent Document 1, a spiral refrigerant passage having a continuous notch is disposed on the outer periphery of the stator core. However, in the spiral groove, the refrigerant immediately flows down, and the stator core There is a possibility that the heat receiving time from the refrigerant to the refrigerant cannot be sufficiently secured and cooling becomes insufficient. In addition, there is a possibility that the cooling capacity of the center portion of the stator core, which is likely to become high temperature, is insufficient.

  An object of the present invention is to provide a stator core having high cooling performance with an inexpensive and simple structure.

In order to achieve the above object, the invention described in claim 1
A stator core (for example, a stator core 10 in an embodiment described later) formed by laminating a plurality of steel plates (for example, a steel plate 11 in an embodiment described later),
On the outer peripheral surface of the stator core (for example, the outer peripheral surface 15 in the embodiments described later), a refrigerant storage portion (for example, refrigerant storage in the embodiments described later) that stores the refrigerant in a region including the axial central portion of the stator core. Part S) is formed.

The invention according to claim 2 is the invention according to claim 1,
The steel plate
A first steel plate in which a first recess (for example, a recess 17B in an embodiment described later) is formed on the outer peripheral surface of the first region (for example, the first region P1 in the embodiment described later);
A second steel plate in which a second recess (for example, a recess 17A in an embodiment described later) is formed on an outer peripheral surface of a second region (for example, a second region P2 in an embodiment described later) different from the first region. And including
The refrigerant storage section is formed by arranging the first steel plate and the second steel plate so as to overlap each other.

In the invention according to claim 3, in the invention according to claim 2,
The first steel plate and the second steel plate have the same shape,
By rolling the first steel plate and the second steel plate, the phases of the first recess and the second recess are different.

The invention according to claim 4 is the invention according to claim 2 or 3,
In the first recess and the second recess, a welded portion (for example, a welded portion 19 in an embodiment described later) that connects the steel plates is formed in the axial direction.

The invention according to claim 5 is the invention according to any one of claims 2 to 4,
A plurality of the refrigerant reservoirs are provided by combining the first recess and the second recess.

Moreover, in invention of Claim 6, in invention of any one of Claims 1-5,
An inclined surface that is smoothly inclined in the circumferential direction (for example, an inclined surface 22 in an embodiment described later) is connected to the refrigerant reservoir.

Further, in the invention described in claim 7, in the invention described in claim 2,
The first recess and the second recess have a V shape in which a central portion in the axial direction of the stator core is recessed in the circumferential direction.

  According to the first aspect of the present invention, since the coolant storing portion for storing the coolant is formed on the outer peripheral surface of the stator core in the region including the central portion in the axial direction of the stator core, the shaft of the stator core that has been difficult to cool so far. The outer peripheral surface at the center in the direction can be appropriately cooled.

  According to invention of Claim 2, the 1st steel plate in which the 1st recessed part was formed in the outer peripheral surface of a 1st area | region, and the 2nd steel plate in which the 2nd recessed part was formed in the outer peripheral surface of a 2nd area | region are piled up. Since the refrigerant storage portion is formed on the outer peripheral surface by being arranged in this manner, the outer peripheral surface of the stator core can be appropriately cooled by the refrigerant remaining in the refrigerant storage portion while increasing the surface area of the stator core and improving the heat dissipation capability.

  According to invention of Claim 3, since the 1st steel plate and the 2nd steel plate are the same shapes, the punching type | mold of a steel plate may be one kind, and the increase in manufacturing cost can be suppressed.

  According to the fourth aspect of the present invention, by providing the welded portion for connecting the steel plates to the first concave portion and the second concave portion in which the outer peripheral surface is recessed, it is possible to prevent the weld portion from protruding from the outer peripheral surface. Further, since the surface area of the stator core is increased in the first recess and the second recess, the cooling capacity is improved.

  According to invention of Claim 5, a cooling capability can be improved by combining a 1st recessed part and a said 2nd recessed part, and providing multiple refrigerant | coolant storage parts.

  According to the sixth aspect of the present invention, since the inclined surface that is smoothly inclined in the circumferential direction is connected to the refrigerant reservoir, the refrigerant discharge performance is improved and the refrigerant is retained in the refrigerant reservoir. Can be prevented from continuing.

  According to the seventh aspect of the present invention, since the first recess and the second recess have a V-shape in which the axial central portion of the stator core is recessed in the circumferential direction, the axial center of the stator core that has been difficult to cool so far. The outer peripheral surface of a part can be cooled appropriately.

It is a perspective view of the stator core of 1st Embodiment of this invention. It is a front view of the steel plate which comprises the stator core shown in FIG. It is explanatory drawing explaining the assembly method of the stator core shown in FIG. It is a perspective view of the stator core of 2nd Embodiment. It is a front view of the steel plate which comprises the stator core shown in FIG. It is an enlarged view of A part of FIG. It is a perspective view of the stator core of the modification of 2nd Embodiment. It is a perspective view of the stator core of 3rd Embodiment.

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

(First embodiment)
FIG. 1 is a perspective view of a stator core according to the first embodiment. As shown in FIG. 1, the stator core 10 of the present embodiment is formed by laminating a plurality of steel plates 11 (see FIG. 2) such as electromagnetic steel plates, and has a substantially annular stator core body 12 and an outer peripheral portion of the stator core body 12. And a plurality of (four in the embodiment shown in the figure) stator core fixing portions 13 provided at equal intervals in the circumferential direction. The stator core fixing portion 13 is provided with a bolt through hole 14 through which a bolt for fixing the stator core 10 to a housing (not shown) or the like is inserted.

  Further, the stator core 10 is arranged in a posture in which a center line O (rotation axis of a rotor not shown) is inclined with respect to a horizontal plane. A refrigerant supply pipe 25 is disposed above the stator core 10 (upper right in the example of FIG. 1), and a refrigerant R such as cooling oil flows from the refrigerant supply pipe 25 to an outer peripheral portion right upper surface 31 (described later) of the stator core 10. It is dripped.

  FIG. 2 is a front view of a steel plate constituting the stator core shown in FIG. As shown in FIG. 2, the steel plate 11 is provided with grooves 16A and 16B at different phases in the circumferential direction. Specifically, among the four outer peripheral surfaces 15 of the stator core body 12 formed between the stator core fixing portions 13, a pair of outer peripheral surfaces 15A disposed on both sides in the circumferential direction across one stator core fixing portion 13A, A pair of grooves 16A and 16B are formed in 15B in a region close to the stator core fixing portion 13A in the circumferential direction.

  More specifically, from the circumferential center line CL connecting the intermediate portion of the outer peripheral surface 15A and the center line O of the stator core 10 to the outer peripheral surface 15A of the stator core fixing portion 13A in the circumferential direction (upper left in FIG. 2). A groove 16A is formed in a region of α ° toward the stator core fixing portion 13A, and an intermediate portion of the outer peripheral surface 15B and the stator core are formed on the outer peripheral surface 15B on the other circumferential side (upper right side in FIG. 2) of the stator core fixing portion 13A. A groove 16B is formed in a region of α ° from the circumferential center line CL connecting the 10 center lines O toward the stator core fixing portion 13A.

  As shown in FIG. 3A, the plurality of steel plates 11 are laminated with the phases being aligned, so that recesses 17A and 17B extending in the stacking direction are formed on the outer peripheral surfaces 15A and 15B by the grooves 16A and 16B. And as shown in FIG.3 (b), the some laminated | stacked steel plate 11 is divided | segmented into two blocks B1, B2 in the approximate center of the lamination direction, and block B2 is rotated 90 degrees with respect to block B1 (FIG. 3). Then, the stator core 10 shown in FIG. 1 is formed by assembling (rolling) clockwise.

  In the following description, the stator core fixing portion 13 where the stator core fixing portion 13A of the block B1 is located is called a top fixing portion 30, and the outer peripheral surface where the outer peripheral surface 15B of the block B1 is located is called an outer peripheral right upper surface 31. The outer peripheral surface on which the outer peripheral surface 15A of B1 is located is referred to as the outer peripheral left upper surface 32.

  Focusing on the right upper surface 31 of the outer peripheral portion of the stator core 10 in FIG. 1 where the refrigerant supply pipe 25 is disposed, the concave portion 17B of the block B1 is a first region P1 on the proximal side of the top fixing portion 30 with respect to the circumferential center line CL. The concave portion 17A of the block B2 is formed in the second region P2 on the distal side of the top fixing portion 30 with respect to the circumferential center line CL. That is, on the outer peripheral right upper surface 31 of the stator core 10, the block is offset in the circumferential direction across the circumferential center line CL, and is offset in the axial direction across the boundary surface M between the block B1 and the block B2. A concave portion 17B of B1 and a concave portion 17A of the block B2 are formed.

  Returning to FIG. 1, when a coolant such as cooling oil dripped from the coolant supply pipe 25 is dropped onto the outer peripheral portion right upper surface 31 of the stator core 10, the coolant flows into the recess 17 </ b> B of the block B <b> 1 and the recess 17 </ b> A of the block B <b> 2. Flowing into. The refrigerant that has flowed into the concave portion 17A of the block B2 is a refrigerant storage portion formed by a step formed by the boundary surface M between the block B1 and the block B2 located in the axial center portion of the stator core 10 and the concave portion 17A of the block B2. Stay in S. As described above, the refrigerant stays in the refrigerant storage portion S for a certain period of time, so that heat is exchanged with the stator core 10 to effectively cool the outer peripheral surface of the stator core 10, particularly the axial central portion of the outer peripheral surface.

  Moreover, since the surface area of the stator core 10 is increased by providing the recesses 17A and 17B, it contributes to cooling by heat dissipation. In the present embodiment, the case where the number of inversions is one time has been shown. However, a plurality of inversions are possible, and the surface area increases as the number of inversions increases, that is, as the block B1 and the block B2 are stacked. This improves heat dissipation efficiency. Note that only the concave portion 17A of the block B1 is formed on the outer peripheral left upper surface 32 of the stator core 10 in FIG. 1, but when the refrigerant supply pipe 25 is also disposed on the outer peripheral upper left surface 32 of the stator core 10, FIG. In the stator core 10 of No. 2, the concave portion is also formed on the lower left surface of the outer peripheral portion, so that the refrigerant reservoir S can be formed on the upper left surface of the stator core 10 of FIG. 1 by the concave portion of the block B2 and the end surface of the block B1. . In the description of the second and subsequent embodiments, an example in which the refrigerant reservoir S is formed only on the right upper surface of the outer periphery of the stator core 10 will be described.

  As described above, according to the stator core 10 according to the present embodiment, the outer peripheral surface 15 of the stator core 10 is formed with the refrigerant storage portion S that stores the refrigerant in the region including the axial center portion of the stator core 10. The outer peripheral surface of the axially central portion of the stator core 10 that has been difficult to cool can be appropriately cooled.

  Further, the outer peripheral surface 15 is formed by overlapping the block B1 in which the concave portion 17B is formed on the outer peripheral surface of the first region P1 and the second block B2 in which the concave portion 17A is formed on the outer peripheral surface of the second region P2. Therefore, the outer peripheral surface 15 of the stator core 10 can be appropriately cooled by the refrigerant remaining in the refrigerant storage portion S while increasing the surface area of the stator core 10 and improving the heat dissipation capability.

  Further, since the cross-sectional shape of the stator core 10 differs in the stacking direction, the torque waveform is different at the positions of the recesses 17A and 17B, and the torque ripple is also reduced.

  Moreover, since the steel plate 11 which comprises the block B1 and the steel plate 11 which comprises the block B2 are the same shape, and it arrange | positions so that the phase of recessed part 17A, 17B may differ by rolling block B1 and block B2. Further, only one type of punching die for the steel plate 11 may be used, and an increase in manufacturing cost can be suppressed.

(Second Embodiment)
FIG. 4 is a perspective view of a stator core according to the second embodiment, and FIG. 5 is a front view of a steel plate constituting the stator core shown in FIG. The stator core of the second embodiment is different from the stator core of the first embodiment in the shape of the groove and the number of rolls. Except for this point, the second embodiment is the same as the first embodiment. Therefore, the same or equivalent parts as those in FIG.

  In the steel plate 11 of the present embodiment, as shown in FIG. 5, the grooves 16C and 16D are in the region of β ° (2α °> β °> α °) from the groove end portion on the side close to the stator core fixing portion 13A, that is, the stator core fixing. It is formed in a region beyond the circumferential center line CL (see FIG. 2) from the groove end near the portion 13A.

  By laminating the plurality of steel plates 11 with the phases aligned, recesses 17C and 17D extending in the stacking direction are formed on the outer peripheral surfaces 15A and 15B by the grooves 16C and 16D. The plurality of stacked steel plates 11 are divided into four blocks B1 to B4 in the stacking direction, the block B2 is rotated by 90 ° with respect to the block B1 (clockwise in FIG. 4), and then the block B3 is changed to this block. The stator core shown in FIG. 4 is rotated by 90 ° with respect to B2 (counterclockwise in FIG. 4), and is assembled (rolled) by rotating block B4 by 90 ° with respect to this block B3 (clockwise in FIG. 4). 10 is formed. In other words, the stator core 10 of the second embodiment is formed by stacking the blocks B1 to B4 three times.

  Focusing on the right upper surface 31 of the outer peripheral portion of the stator core 10 of FIG. 4 where the refrigerant supply pipe 25 is disposed, the concave portion 17D of the blocks B1 and B3 is the first on the proximal side of the top fixing portion 30 with respect to the circumferential center line CL. The recesses 17C of the blocks B2 and B4 are formed in the region P1, and are formed in the second region P2 on the distal side of the top fixing part 30 with respect to the circumferential center line CL. That is, on the right upper surface 31 of the outer peripheral portion of the stator core 10, the concave portion 17 </ b> C is offset in the circumferential direction across the circumferential center line CL and offset in the axial direction across the boundary surface M between the blocks B <b> 1 to B <b> 4. , 17D are formed.

  In the present embodiment, since the grooves 16C and 16D formed in the steel plate 11 are formed in a region beyond the circumferential center line CL, the recesses 17C and 17D of the blocks B1 to B4 are formed so as to be continuous in the axial direction. The

  When refrigerant such as cooling oil dripping from the refrigerant supply pipe 25 is dropped on the outer peripheral right upper surface 31 of the stator core 10, the refrigerant flows into the recesses 17C and 17D of the blocks B1 to B4. The refrigerant flowing into the concave portion 17C of the block B2 remains in the refrigerant storage portion S formed by the step formed on the boundary surface M between the block B1 and the block B2 and the concave portion 17C of the block B2, and enters the concave portion 17C of the block B4. The refrigerant that has flowed in remains in the refrigerant storage portion S formed by a step formed at the boundary surface M between the block B3 and the block B4 and the concave portion 17C of the block B4. As described above, the refrigerant stays in the refrigerant storage portion S for a certain period of time, so that heat is exchanged with the stator core 10 to effectively cool the outer peripheral surface of the stator core 10, particularly the axial central portion of the outer peripheral surface.

  As described above, according to the stator core 10 according to the present embodiment, the outer peripheral surface 15 of the stator core 10 is formed with the refrigerant storage portion S that stores the refrigerant in the region including the axial center portion of the stator core 10. The outer peripheral surface of the axially central portion of the stator core 10 that has been difficult to cool can be appropriately cooled. The central portion in the axial direction of the stator core 10 means a portion that is separated from the end face of the stator core 10, and does not mean only a portion that is equidistant from both end faces of the stator core 10.

  Further, the blocks B1 and B3 in which the recesses 17D are formed on the outer peripheral surface of the first region P1 and the blocks B2 and B4 in which the recesses 17C are formed on the outer peripheral surface of the second region P2 are arranged so as to overlap each other. Since the refrigerant storage portion S is formed on the surface 15, the outer peripheral surface 15 of the stator core 10 can be appropriately cooled by the refrigerant remaining in the refrigerant storage portion S while increasing the surface area of the stator core 10 and improving the heat dissipation capability.

  Moreover, the cooling capacity can be improved by combining the recesses 17C and 17D and providing a plurality of the refrigerant reservoirs S.

  Further, in the refrigerant storage section S of the block B2, a large amount of refrigerant is stored and effectively cooled. However, if the residence time is too long, the temperature of the refrigerant becomes high and the cooling effect may be reduced. For this reason, it is desirable to discharge after having stayed for an appropriate time. Therefore, as shown in FIG. 6, it is preferable to provide an inclined surface 22 on the wall 20 of the recess 17C on the downstream side of the refrigerant, and discharge the refrigerant after an appropriate residence time.

  Further, as shown in FIG. 7, a welded portion 19 that welds the steel plate 11 integrally may be provided in the recesses 17 </ b> C and 17 </ b> D that are continuous in the axial direction in order to prevent the steel plate 11 from being scattered. The welded portion 19 can be formed by a single straight line passing through the recesses 17C and 17D that are continuous in the axial direction, and the welded portion in the conventional stator core in which the recesses are formed in a spiral shape or a ring shape is inclined or stepped. It can be easily formed as compared with the welded part.

  In addition, the welding part 19 may provide the protrusion part (not shown) which protrudes radially outward inside the recessed part 17C, 17D, and may make it weld this protrusion part. Since the welded portion 19 is in the recesses 17 </ b> C and 17 </ b> D, the welded portion 19 does not protrude from the outer peripheral surface 15 of the stator core 10, and the degree of freedom in the layout of the stator core 10 is improved.

  Furthermore, when the refrigerant is injected from the side, the recesses 17C and 17D may be provided with a gradient or a step that lowers the refrigerant injection side to increase the residence time of the refrigerant.

(Third embodiment)
FIG. 8 is a perspective view of the stator core 10 of the third embodiment. In the stator core 10 of the third embodiment, the concave portion 17 is formed in a substantially V-shape that is recessed in the circumferential direction on the outer peripheral right upper surface 31 of the stator core 10. In addition, the same code | symbol or an equivalent code | symbol is attached | subjected to the same or equivalent part as 1st Embodiment, and description is simplified or abbreviate | omitted.

  As shown in FIG. 4, in the stator core 10 of the present embodiment, the grooves 16 having the same circumferential length are formed such that the circumferential phase is different from each other, for example, the circumferential phase is increased by a predetermined angle. By laminating a large number of steel plates 11 in the order in which the circumferential phase of the grooves 16 gradually increases and gradually decreases, a substantially V-shaped recess 17 that is recessed in the circumferential direction is formed.

  By making the concave portion 17 substantially V-shaped recessed in the circumferential direction, the dropped refrigerant concentrates in the refrigerant storage portion S formed in the vicinity of the V-shaped trough portion 26, and the vicinity of the trough portion 26 is intensively cooled. It becomes possible to do. The position and number of the valleys 26 can be freely set by changing the stacking order of the steel plates 11. Therefore, if the valley portion 26 is set at the center in the axial direction, the outer peripheral surface 15 at the center portion in the axial direction of the stator core 10 that is likely to be hot can be appropriately cooled.

  Further, the V-shaped valley portion 26 is not limited to one, and a plurality of V-shaped valley portions 26 can be provided, and it is possible to effectively cool the target portion to be cooled.

  As described above, according to the stator core 10 according to the present embodiment, the concave portion 17 has a V-shape in which the central portion in the axial direction is recessed in the circumferential direction, and thus the central portion in the axial direction of the stator core 10 that has been difficult to cool so far. The outer peripheral surface 15 of the part can be cooled appropriately.

In addition, this invention is not limited to each embodiment mentioned above, A deformation | transformation, improvement, etc. are possible suitably.
In addition, in 1st and 2nd embodiment, although the refrigerant | coolant storage part was formed by forming a recessed part in a different area | region by rolling a steel plate of the same shape, it is not necessary to roll a steel plate of the same shape. Alternatively, the concave portions may be formed in different regions by laminating steel plates having different shapes, thereby forming the refrigerant reservoir. That is, the first steel plate and the second steel plate may have the same shape or different shapes.

DESCRIPTION OF SYMBOLS 10 Stator core 11 Steel plate 15 Outer peripheral surface 17-17D Concave part 19 Welding part 22 Inclined surface P1 1st area | region P2 2nd area | region S Refrigerant storage part

Claims (7)

A stator core formed by laminating a plurality of steel plates,
A stator core in which a refrigerant reservoir for storing refrigerant is formed in an outer peripheral surface of the stator core in a region including an axial central portion of the stator core. The stator core according to claim 1,
The steel plate
A first steel plate in which a first recess is formed on the outer peripheral surface of the first region;
A second steel plate having a second recess formed on the outer peripheral surface of the second region different from the first region,
A stator core in which the refrigerant reservoir is formed by overlapping the first steel plate and the second steel plate. The stator core according to claim 2,
The first steel plate and the second steel plate have the same shape,
A stator core in which the phases of the first recess and the second recess are different by rolling the first steel plate and the second steel plate. The stator core according to claim 2 or 3,
The stator core in which the welding part which connects the said steel plates is formed in the said 1st recessed part and the said 2nd recessed part over the axial direction. The stator core according to any one of claims 2 to 4, wherein
A stator core in which the first recess and the second recess are combined to provide a plurality of the refrigerant reservoirs. The stator core according to any one of claims 1 to 5,
A stator core, to which the inclined surface that smoothly inclines in the circumferential direction is connected to the refrigerant reservoir. The stator core according to claim 2,
The first concave portion and the second concave portion have a V-shape in which a central portion in the axial direction of the stator core is recessed in the circumferential direction.

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