JP2007074853A - Stator structure of rotating electric machine - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a stator structure of a rotating electric machine that is easy in being assembled at the manufacturing of the rotating electric machine, and improved in heat dissipation to cooling passages form a stator core. <P>SOLUTION: In the stator structure of the rotating electric machine, the rotating electric machine comprises: a stator 5 in which a coil 2 is wound to the stator core 1, and the stator 1 is fixed to a box; and a rotor 6. The stator structure is also characterized in that: a plurality of penetration holes 10 that extend in the axial direction are formed at the external periphery of the stator core 1; some of the plurality of penetration holes 10 are used as the cooling passages; and the remaining penetration holes are used as the penetration holes for penetrating fixing means for fixing the stator core to the box. <P>COPYRIGHT: (C)2007,JPO&INPIT

Description

  The present invention relates to a stator structure of a rotating electric machine used for electric vehicles, hybrid vehicles, and other industrial equipment.

  A rotating electric machine having a rotor provided with a permanent magnet is used in many electric vehicles, hybrid vehicles, or industrial machines for reasons such as low loss, high efficiency, and high output. In such a rotating electrical machine, in order to cool the stator core, for example, as described in Patent Document 1 and Patent Document 2, a cooling path is formed in the casing of the rotating electrical machine to cool the stator core. It has been broken. However, in the rotating electrical machine having such a structure, in order to secure heat removal from the stator core to the cooling path of the housing, the stator core needs to be in close contact with the housing. Specifically, in manufacturing the rotating electrical machine, There was a problem that a somewhat difficult assembly method had to be adopted such as press fitting or shrink fitting the stator core into the housing.

  On the other hand, in order to improve assemblability, as described in Patent Documents 3 and 4, a structure in which the stator core is simply fixed to the casing with a bolt or the like is conceivable, but the stator core is fixed to the casing with a bolt or the like. In order to fit the stator core into the casing in advance, it is necessary to provide a gap in the fitting portion, and heat removal from the stator core to the cooling path of the casing deteriorates due to the high thermal resistance of the gap. There was a problem of saying that.

In order to enhance the cooling effect of the stator core by the cooling path, as described in Patent Document 5, a cooling path is provided by providing a recess extending in the axial direction on the outer peripheral side of the stator core and covering the recess with a side plate. A structure in which both ends of the stator core are sandwiched between end plates that supply a cooling liquid is proposed, but in a rotating electric machine having such a structure, a portion that is exposed to the outside of the stator core is not subjected to rust prevention treatment. There was a problem such as not becoming.
JP 2004-229418 A JP-A-6-327180 Japanese Patent Laid-Open No. 7-31086 JP-A-6-245415 JP-A-9-51656

  The present invention aims to solve the above-described problems, and the purpose thereof is to facilitate assembly during manufacture of the rotating electrical machine, and to remove heat from the stator core to the cooling path. A stator structure is provided.

  A stator structure of a rotating electrical machine according to the present invention is a rotating electrical machine including a stator in which a coil is wound around a stator core and the stator core is fixed to a casing, and a rotor. A plurality of through-holes extending in the axial direction are provided, some of the plurality of through-holes are used as cooling paths, and the remaining through-holes are inserted through holes for fixing means for fixing the stator core to the housing. It is characterized by using.

  According to this, by fixing the stator core to the housing with a fixing means such as a bolt, the assembly of the rotating electrical machine can be facilitated, and by providing the cooling path on the outer peripheral side portion of the stator core, Heat removal from the stator core to the cooling path can be improved. In addition, it is possible to facilitate the rollover of the electromagnetic steel sheets constituting the stator core by providing the cooling passages and the insertion holes by distributing the plurality of through holes. Here, the term “rolling” refers to rotating and laminating the electromagnetic steel sheets by a certain angle in order to cancel out the magnetic property bias occurring in the rolling direction during the production of the electromagnetic steel sheets. Furthermore, compared with the rotating electrical machine described in Patent Document 5, since the stator core is not exposed to the outside, it is possible to omit performing an antirust treatment on the exposed portion of the stator core.

Hereinafter, embodiments of the present invention will be described with reference to the drawings.
FIG. 1 is a schematic sectional view showing an embodiment of a stator structure of a rotating electrical machine according to the present invention including a central axis.
In this rotating electrical machine, a stator 2 configured by winding a coil 2 around a stator core 1 and fixing the stator core 2 to the case 3 among the case 3 and the cover 4 constituting the casing, With The rotor 6 is configured by fitting a shaft 8 to a rotor core 7, and the shaft 8 is rotatably supported by the case 3 via a bearing 9.

A plurality of through holes 10 extending in the axial direction are provided in the outer peripheral side portion of the stator core 1. Some of the plurality of through holes 10 are used as cooling paths, and the remaining through holes 10 are used as the stator core. It is used as an insertion hole for inserting a bolt 11 as a fixing means for fixing to the casing. (Equivalent to claim 1)
The lower half in FIG. 1 shows a cross section including a through hole 10 used as a cooling path, and the upper half shows a cross section including a through hole 10 used as an insertion hole.

  A cooling pipe 12 is inserted into the through hole 10 used as a cooling path so that the outer peripheral surface thereof is in close contact with the inner peripheral surface of the through hole 10, and the case 3 has a substantially annular flow path 13, An inflow part 14 that communicates the flow path 13 and the cooling pipe 12 is provided, and an outflow part 15 that communicates the flow path 12 and the cooling pipe 11 is provided in the cover 4. As a result, a cooling system is configured, and the refrigerant in the flow path 13 is circulated in the order of the flow path 13, the inflow part 14, the cooling pipe 12, the outflow part 15, and the flow path 13, and from the stator core 1 to the cooling pipe 11. Heat is removed to the refrigerant inside.

As the refrigerant used in this cooling system, it is common to use cooling water in general, but it is also possible to use cooling oil or the like. Also, the bolt 11 can be other fixing means such as a rivet.
In addition, 16 in FIG. 1 shows the cooling pipe insertion hole which inserts the cooling pipe 12 with respect to the cover 4, 17a, 17b shows the inflow path 17a and the outflow path 17b which flow in and out of the refrigerant | coolant to the flow path 13, Reference numerals 18a and 18b denote flow path plugs.

  In the rotating electrical machine shown in FIG. 1, when the coil 2 is excited by an inverter (not shown), a rotating magnetic field is formed in the circumferential direction of the stator 5, and a plurality of permanent magnets (not shown) having different polarities alternately embedded in the circumferential direction. Is attracted and repelled by the rotating magnetic field generated by the stator 3, and the rotor 6 rotates at a synchronous speed with the rotating magnetic field.

FIG. 2 is a schematic perspective view showing an embodiment of a stator structure of a rotating electrical machine according to the present invention.
Here, the coil and the teeth for winding the coil formed on the inner peripheral side of the stator core are not shown.
As shown in FIG. 2, the stator core 7 is configured by laminating electromagnetic steel plates, and a portion protruding to the outer peripheral side here is provided on the outer peripheral portion thereof, and four through holes 10 are provided in the peripheral portion in the peripheral portion. 2, the pair of left and right through holes 10 in FIG. 2 are used as insertion holes for inserting bolts 11 as fixing means, and the pair of upper and lower through holes 10 are used as cooling paths for inserting cooling pipes 12. .

  Thus, by providing the through holes 10 at equal intervals in the circumferential direction, when the stator core 7 is configured by laminating electromagnetic steel sheets, in order to cancel out the magnetic property bias that occurs in the rolling direction during the production of the electromagnetic steel sheets, It is possible to enable so-called inversion, in which electromagnetic steel sheets are rotated by a certain angle and stacked. Of course, it goes without saying that the diameters of the respective through holes 10 need to be matched.

FIG. 3 is a schematic view showing an embodiment of a stator structure of a rotating electrical machine according to the present invention as seen from the central axis direction.
Also here, the coil and the teeth for winding the coil formed on the inner peripheral side of the stator core are not shown.

  FIG. 3A shows an outer peripheral portion of the stator core 7, here, four ear-shaped portions projecting to the outer peripheral side are provided at equal intervals in the circumferential direction, and four through-holes 10 are equally spaced in the circumferential direction in the portion. The pair of left and right through holes 10x is used as an insertion hole through which a bolt 11 as a fixing means passes, and the pair of upper and lower through holes 10y is used as a cooling path into which the cooling pipe 12 is inserted. The cooling paths are alternately provided in the circumferential direction (corresponding to claim 3), and the cooling paths are provided at equal intervals in the circumferential direction. As a result, heat removal from the stator core 7 to the cooling path can be performed uniformly in the circumferential direction, and the stator core 7 can be cooled uniformly in the circumferential direction.

  FIG. 3B shows an outer peripheral portion of the stator core 7, here, six ear-shaped portions protruding to the outer peripheral side at equal intervals in the circumferential direction, and six through holes 10 at equal intervals in the circumferential direction. The upper and lower pair of through holes 10x are used as insertion holes through which the bolts 11 as the fixing means pass, and the other through holes 10y are used as cooling paths into which the cooling pipes 12 are inserted. Are arranged periodically. According to this, it is possible to increase the number of heat extraction points from the stator core 7 to the cooling path, and to cool the stator core 7 more effectively.

  3 (a) and 3 (b), the stator core 7 is provided with an ear-like portion protruding outward and the through hole 10 is provided therein. However, as shown in FIG. 3 (c), the stator core 7 Six through-holes 10 may be provided at equal intervals in the circumferential direction at the outer peripheral side portion, that is, at the portion located inside the outer peripheral circle.

Table 1 shows a permutation example of the insertion hole 10x and the cooling path 10y when the number of the through holes 10 is three to twelve. In Table 1, for convenience, the insertion hole is indicated by x and the cooling path is indicated by y.
In order to achieve both the fixing of the stator core to the casing by the bolts and the heat removal and cooling of the stator core by the cooling path, it is preferable to periodically arrange the through holes and the cooling path. Although an even number is preferably provided, an odd number may be provided as long as the fixing of the stator core to the casing by the bolt is secured.

図４は本発明に係る回転電機のステータ構造の一実施形態を冷却管を含む断面で示す模式断面図である。
冷却路を、貫通穴１０に冷却管１２を挿通して構成し、冷却管１２を貫通穴１０に挿入した後、冷却管１２を内部加圧して、冷却管１２のステータコア７の軸方向外側に位置する部分を、図４に示すように拡径することで、ステータコア７を構成する複数の電磁鋼板を相互に締結する。（請求項２に相当）

FIG. 4 is a schematic cross-sectional view showing an embodiment of a stator structure of a rotating electrical machine according to the present invention in a cross section including a cooling pipe.
The cooling path is configured by inserting the cooling pipe 12 through the through hole 10, and after inserting the cooling pipe 12 into the through hole 10, the cooling pipe 12 is internally pressurized to the outside of the cooling pipe 12 in the axial direction of the stator core 7. A plurality of electromagnetic steel sheets constituting the stator core 7 are fastened to each other by expanding the diameter of the positioned portion as shown in FIG. (Equivalent to claim 2)

As a result, it is possible to fasten a plurality of electrical steel sheets to each other without using a fixing-dedicated structure, although the electrical steel sheets are conventionally fastened together by means such as caulking, welding, and bonding. .
In addition, the diameter of the portion of the cooling pipe inserted into the stator core 7 can be increased, and the outer peripheral surface of the cooling pipe 12 can be brought into close contact with the inner peripheral surface of the through hole 10. The heat can be extracted to the refrigerant more effectively, and the stator core 7 can be cooled more effectively.

Both ends 12a and 12b in the axial direction of the cooling pipe 12 are inserted and fitted into the cover 4 and the case 3 shown in FIG. 1, but by tightening the fitting, the bolts as described above are not used. In addition, the stator core 7 can be fixed to the housing by the cooling pipe 12.
As described above, when the stator core 7 is fixed to the housing by the cooling pipe 12, the cooling pipe 12 itself is required to have a strength that can withstand the motor torque transmission, and the cooling pipe 12 needs to be reinforced to have a large thickness. However, as shown below, since the bolts as the fixing means can be eliminated and all of the through holes 10 can be used as cooling paths, it is possible to improve the cooling performance and realize uniform cooling over the entire circumference. it can.

  Here, all of the plurality of through holes 10 can be used as cooling paths, the cooling paths can be configured by inserting the cooling pipes 12 through the through holes 10, and the stator core can be fixed to the casing by the cooling pipes 12, According to this, since the bolt as the fixing means can be eliminated and the number of cooling paths can be increased, the stator core 7 can be cooled more effectively.

  Even when all of the plurality of through holes 10 are used as cooling paths in this way, the cooling pipe 12 is inserted into the through hole 10 and the cooling pipe 12 is inserted into the through hole 10. The portion of the cooling pipe 12 positioned outside the stator core 7 in the axial direction is expanded in diameter as shown in FIG. 4, whereby a plurality of electromagnetic steel plates constituting the stator core 7 can be fastened together. it can. (Equivalent to claim 5)

According to this, in the past, electromagnetic steel sheets were mutually fastened by means of caulking, welding, bonding, etc., but a plurality of electrical steel sheets were fastened together without using these dedicated fixing structures. Can do.
In addition, the diameter of the portion of the cooling pipe inserted into the stator core 7 can be increased, and the outer peripheral surface of the cooling pipe 12 can be brought into close contact with the inner peripheral surface of the through hole 10. The heat can be extracted to the refrigerant more effectively, and the stator core 7 can be cooled more effectively.

FIG. 5 is a schematic view showing the refrigerant flow in the stator structure of the rotating electrical machine according to the present invention as seen from the axial direction.
The reference numerals in FIG. 5 are the same as those shown in FIG. 1, and in FIG.
The refrigerant flows into the flow path 13 provided in the case 3 from the inflow path 17a, and is cooled through the flow path 13 and the inflow portion 14 extending in the radial direction formed in the case 3 by drilling or casting. Is supplied to the pipe 12, and further, is supplied to the flow path 13 located on the opposite side to the inflow path 17a through the outflow portion 15 provided in the cover 3 so as to be inclined with respect to the radial direction. It is supplied to the flow path 13 through the inflow part 14, the cooling pipe 12, and the outflow part 15, and is discharged | emitted from the outflow path 17b.

  In addition, this invention is not limited only to the said embodiment, Many deformation | transformation or a change is possible. In the best mode for carrying out the invention, the operation of the rotating electrical machine is explained in an AC synchronous motor. However, the stator structure of the rotating electrical machine of the present invention is applied to a DC brushless motor or an induction motor. Is also possible.

  The present invention is suitable for use in a stator of a rotating electrical machine, facilitates assembly during manufacture of the rotating electrical machine, and can improve heat removal from the stator core to the cooling path.

1 is a schematic cross-sectional view showing an embodiment of a stator structure of a rotating electrical machine according to the present invention including a central axis. It is a model perspective view which shows one Embodiment of the stator structure of the rotary electric machine which concerns on this invention. It is a schematic diagram which shows one Embodiment of the stator structure of the rotary electric machine which concerns on this invention seeing from a central axis direction. It is a schematic cross section which shows one Embodiment of the stator structure of the rotary electric machine which concerns on this invention in the cross section containing a cooling pipe. It is a schematic diagram which shows the flow of the refrigerant | coolant of the stator structure of the rotary electric machine which concerns on this invention seeing from an axial direction.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Stator core 2 Coil 3 Case 4 Cover 5 Stator 6 Rotor 7 Rotor core 8 Shaft 9 Bearing 10 Through hole 11 Bolt 12 Cooling pipe 13 Flow path 14 Inflow part 15 Outflow part 16 Cooling pipe insertion hole 17a Inflow path 17b Outflow path 18a Flow path plug 18b Channel plug

Claims (5)

A rotating electric machine comprising a stator formed by winding a coil around a stator core and fixing the stator core to a casing, and a rotor, and provided with a plurality of through holes extending in the axial direction on the outer peripheral side portion of the stator core, A stator for a rotating electrical machine, wherein some of the plurality of through holes are used as cooling passages, and the remaining through holes are used as insertion holes through which fixing means for fixing the stator core to the housing are inserted. Construction. The cooling path is configured by inserting a cooling pipe through the through hole, and after inserting the cooling pipe into the through hole, the cooling pipe is internally pressurized to expand the diameter, thereby forming a plurality of stator cores. The stator structure for a rotating electrical machine according to claim 1, wherein the electromagnetic steel plates are fastened to each other. The stator structure for a rotating electrical machine according to claim 1 or 2, wherein the cooling path and the insertion hole are alternately provided in a circumferential direction. A rotating electric machine comprising a stator formed by winding a coil around a stator core and fixing the stator core to a casing, and a rotor, and provided with a plurality of through holes extending in the axial direction on the outer peripheral side portion of the stator core, A rotating electrical machine characterized in that all of the plurality of through holes are used as cooling paths, the cooling path is configured by inserting a cooling pipe through the through holes, and a stator core is fixed to the casing by the cooling pipe. Stator structure. The plurality of electromagnetic steel plates constituting the stator core are fastened to each other by inserting the cooling pipe into the through hole and then pressurizing the cooling pipe to expand the diameter. Stator structure for rotating electrical machines.

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