JP2012222929A - Stator for rotary electric machine - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a stator for a rotary electric machine having a configuration including split cores, which achieves a configuration which can reduce the cost, can facilitate design and management of fastening force, enables easy manufacture of each component, and also has a cooling function without having a cooling dedicated component provided therein.SOLUTION: The stator includes a core body 24 constituted of a plurality of split cores 18 arranged annularly, and an external cylinder 20 which is a metal pipe wound around the outer periphery of the core body 24. Both end side parts of the external cylinder 20 are formed by bending radially outward. The both end side parts of the external cylinder 20 and the outer periphery face of the core body 24 are simultaneously welded and fixed.

Description

  The present invention relates to a stator for a rotating electrical machine including a plurality of divided cores arranged in an annular shape.

  Conventionally, rotating electric machines have been used as motors and generators in hybrid vehicles, electric vehicles, fuel cell vehicles, and the like that travel using an engine and a motor as drive sources. Further, the rotating electrical machine may be used as having both functions of a motor and a generator. The rotating electrical machine includes a stator and a rotor that is disposed to face the stator and rotates. As such a stator, in order to suppress iron loss at high frequency, a stator core using a metal magnetic powder green compact with an insulating coating treatment or a metal magnetic powder green compact with a resin added is used. It is possible to do.

  For example, in Patent Literature 1, the outer peripheral thin plate is wound around the outer periphery of a plurality of divided cores arranged in an annular shape, and the ears that are bent portions formed by bending the circumferential end of the outer peripheral thin plate radially outward are welded together. The outer peripheral thin plate and the plurality of divided cores are fitted together.

  Also, a plurality of sandwiching pieces provided at intervals in the circumferential direction so as to face the axial direction of the outer peripheral thin plate, and the split core is sandwiched by the sandwiching pieces provided by bending the tongue piece radially inward. Yes. Further, the sandwiching piece is fitted into a recess formed in the end surface in the axial direction of the yoke portion of the split core, thereby positioning the split core in the circumferential direction.

JP 2007-195281 A

  In the stator described in Patent Document 1 above, the outer peripheral thin plate provided on the outer peripheral portion for positioning the split core has a sandwich piece that is a bent portion, and only requires a pressing step for forming the outer peripheral thin plate. Instead, the press mold becomes complicated. Moreover, the bending process of a clamping piece is also needed. Such an increase in the number of processes causes an excessive increase in cost.

  Moreover, unless the dimension of the fitting part with respect to the other member of an outer periphery thin plate and a split core is made highly accurate, the positioning accuracy of an outer periphery thin plate and a split core tends to become inadequate. For example, it is necessary to bend and fix in accordance with the assembled state in which the bending accuracy itself of the sandwiching piece of the outer peripheral thin plate, the dimension of the sandwiching piece, and the dimensional variation of individual parts overlap. For this reason, a stator with a split core can be used to easily manage the tightening force by designing and dimensional management for variations in tightening allowance during installation, reducing the dimensional accuracy between mounting parts, and facilitating the manufacture of each part. Realization of is desired. Furthermore, when another component dedicated to cooling is provided in the stator in order to cool the stator, the number of components increases and the cost may increase excessively. For this reason, it is also desired that a stator having a split core has a cooling function without providing a dedicated cooling component.

  The present invention relates to a stator for a rotating electrical machine, in a configuration including a split core, can reduce costs, can easily manage a design and tightening force, can easily manufacture each component, and can be used only for cooling. It aims at realizing the structure which gives a cooling function, without providing.

  A stator for a rotating electrical machine according to the present invention includes a plurality of divided cores arranged in an annular shape, and a metal tube wound around the outer periphery of the plurality of divided cores, and a portion near both ends of the metal tube, and an annular shape. A stator for a rotating electrical machine, wherein the outer circumferences of a plurality of divided cores arranged are fixed by welding at the same time.

  Moreover, in the stator for a rotating electrical machine according to the present invention, preferably, the metal pipe is formed in a rectangular cross section, and both end portions are welded and fixed at the same time in a state in which the metal pipe is rounded around the outer periphery of the plurality of divided cores.

  In the stator for a rotating electrical machine according to the present invention, preferably, the metal pipe is wound around the outer periphery of the plurality of divided cores by a plurality of turns.

  In the stator for a rotating electrical machine according to the present invention, preferably, the metal tube is a first metal tube wound around a circumferential one side portion of the outer periphery of the plurality of split cores, and further, the outer periphery of the plurality of split cores A second metal tube wound around the other side portion in the circumferential direction, and a portion of the outer periphery of the plurality of split cores arranged in an annular shape and the portions near the one end of the first and second metal tubes; The portions near the other ends of the second metal pipes and other portions on the outer periphery of the plurality of split cores arranged in an annular shape are simultaneously welded and fixed.

  In the stator for a rotating electrical machine according to the present invention, preferably, the metal tube has a flat rectangular cross section having an outer shape along the axial direction on the outer peripheral surface of the plurality of divided cores, and at least the axial direction of the metal tube One end face has a refrigerant ejection hole formed in a direction orthogonal to the flow in the metal tube.

  According to the stator for a rotating electrical machine according to the present invention, in a configuration including a split core, a plurality of split cores can be integrally fixed in an annular shape with a simple tube shape, so that the cost can be reduced without using a complicated press die. . In addition, it is possible to easily manage the design and tightening force with respect to variations in tightening allowance during assembly. Further, it is not necessary to excessively increase the dimensional accuracy between the parts to be assembled, and each part can be easily manufactured. Furthermore, the cooling function can be given to the stator without providing a cooling-dedicated component by allowing the coolant to flow through the metal pipe, which is an assembly component.

It is a figure which shows the stator core which comprises the stator for rotary electric machines of embodiment of this invention. It is the A section enlarged view of FIG. FIG. 3 is a cross-sectional view taken along the line B-B in FIG. 2, showing a stator having a coil wound around a stator core. It is a figure corresponding to FIG. 3 which shows the stator for rotary electric machines of the 1st example of another example of embodiment of this invention. It is a figure corresponding to FIG. 3 which shows the stator for rotary electric machines of the 2nd example of another example of embodiment of this invention. It is a figure corresponding to FIG. 3 which shows the stator for rotary electric machines of the 3rd example of another example of embodiment of this invention. It is a figure which shows the stator core which comprises the stator for rotary electric machines of the 4th example of another example of embodiment of this invention. It is a figure corresponding to FIG. 3 which shows the stator for rotary electric machines of the 5th example of another example of embodiment of this invention.

  Hereinafter, embodiments according to the present invention will be described in detail with reference to the drawings. 1 to 3 show an example of an embodiment of the present invention. As shown in FIG. 1, a stator 10 (FIG. 3) that is a rotating electrical machine constituting a rotating electrical machine used as a motor or a generator includes an annular stator core 12 and an inner periphery of the stator core 12. A coil 16 (FIG. 3) wound by concentrated winding or distributed winding is provided on a tooth 14 provided so as to protrude in a radial direction at a plurality of locations in the circumferential direction of the section. The stator core 12 includes a plurality of divided cores 18 arranged in an annular shape so as to be adjacent to each other in the circumferential direction, and an outer cylinder that is a pipe-shaped metal tube wound around the outer peripheral surface of the plurality of divided cores 18 in the circumferential direction. 20.

  As shown in detail in FIG. 2, each divided core 18 includes a yoke element 22 provided on the outer peripheral portion in the assembled state, and a tooth 14 provided on a portion on the inner peripheral side of the yoke element 22 in the assembled state. And have. The divided cores 18 are arranged so that a plurality of the divided cores 18 are adjacent to each other in an annular shape, and constitute a core body 24. A coil 16 (FIG. 3) is wound around each tooth 14.

  As shown in FIG. 1, the outer cylinder 20 which is a metal tube and is formed in a substantially cylindrical shape is wound around the outer peripheral surface of the core main body 24 so as to be in close contact therewith. As shown in FIGS. 1 and 3, the outer cylinder 20 has an axial length that is substantially the same as the overall axial length of the core body 24, along the axial direction on the cylindrical outer peripheral surface of the core body 24. It is provided with a rectangular cross section. Then, the outer cylinder 22 is wound around the outer peripheral surface of the core body 24 in a circumferential direction so as to be rounded and tightened into a substantially cylindrical shape along the outer peripheral surface of the core main body 24, and the portions of the outer cylinder 20 near the both ends are opposed to each other. The bent portion 26 is formed by bending outward in the radial direction. Further, a gap 27 (FIG. 2) is provided between the portions of the outer cylinder 20 near both ends in the circumferential direction.

  And the part near the circumferential direction both ends of the outer cylinder 20 and the circumferential direction one part of the outer peripheral surface of the core main body 24 are weld-fixed simultaneously by the welding part 28 shown with a shaded part in FIG. 1, FIG. That is, the portions near both ends of the outer cylinder 20 and the outer peripheral portion of the split core 18 are fixed by welding at the same time. In the illustrated example, adjacent end portions of the two split cores 18 are located between both ends of the outer cylinder 20 in the circumferential direction of the core body 24, so The portions near both ends of the tube 20 are welded and fixed simultaneously. However, with respect to the circumferential direction of the core main body 24, when the central portion in the circumferential direction of the single divided core 18 is positioned between both ends of the outer cylinder 20 in the circumferential direction, the single divided core 18 and the outer cylinder 20 are located. It is also possible to weld and fix the portions near both ends of the same.

  Thus, when the outer cylinder 20 is wound around the outer periphery of the split core 18, a cylindrical jig (not shown) can be fitted inside the plurality of split cores 18 arranged in an annular shape. Further, when the outer cylinder 20 is manufactured, the metal tube having a round cross section is crushed and formed into a flat shape with a rectangular cross section, and then rounded into a cylindrical shape, or a metal tube having a rectangular cross section is rounded into a cylindrical shape. be able to.

  Further, as shown in FIG. 3, a refrigerant passage 29 is provided inside the outer cylinder 20, and as shown in FIG. 2, one end portion of the outer cylinder 20 facing the radially outer side serves as a refrigerant inlet 30, and the outer cylinder 20 The other end portion that faces radially outward can be the refrigerant outlet 32. The core body 24 is cooled by flowing a coolant, for example, coolant such as coolant or cooling oil such as automatic transmission fluid (ATF) from the coolant inlet 30 toward the coolant outlet 32 and into the outer cylinder 20. Can do. For this reason, the outer cylinder 20 may be made of a material having high thermal conductivity, such as aluminum or an aluminum alloy. Further, at the time of use, the refrigerant inlet 30 and the refrigerant outlet 32 are connected to both ends of a refrigerant path (not shown), a heat exchange part and a refrigerant pump are provided in the middle of the refrigerant path, and the refrigerant including the refrigerant path and the outer cylinder 20 Circulate the refrigerant in the circulation path. In this case, the heat exchange unit causes the refrigerant to exchange heat with air, other refrigerants, and the like to cool the refrigerant. Moreover, when using cooling oil as a refrigerant | coolant, it can cool by providing an oil pan instead of a heat exchange part, and letting a refrigerant | coolant pass through an oil pan.

  In such a stator core 12, the coil 10 is wound around the teeth 14 to form the stator 10 (FIG. 3), and the stator 10 is fitted and fixed inside a housing (not shown) or is shown on the outer periphery of the stator 10. The brackets that are not to be joined can be joined and fixed to a fixing portion (not shown) by the brackets. As shown in FIG. 3, a coil end 34 is formed by a portion of the coil 16 that protrudes in the axial direction from both axial end surfaces of the stator core 12.

  According to such a stator 10, in the configuration including the split cores 18, the plurality of split cores 18 can be integrally fixed in an annular shape with a simple tube-shaped outer cylinder 20, so that a complicated press die is not used. Cost can be reduced. In addition, it is possible to easily manage the design and tightening force with respect to variations in tightening allowance during assembly. That is, unlike the present embodiment, unlike the case where a plurality of split cores arranged in an annular shape are fixed by shrink fitting or press-fitting with the outer cylindrical portion, variation in tightening allowance when the core body 24 is fixed to the outer cylinder 20 is different. The design and tightening force can be easily managed.

  Further, since the plurality of split cores 18 and the outer cylinder 20 wound around the split core 18 can be fixed simultaneously by welding, the positioning accuracy of the split core 18 with respect to the outer cylinder 20 is good, and the dimensional accuracy required for the component parts is increased. Can be lowered. That is, it is not necessary to excessively increase the dimensional accuracy between the parts to be assembled, which are the outer cylinder 20 and the split core 18, and each part can be easily manufactured. In addition, since the outer cylinder 20 has a simple shape and is wound around the split core 18, it is possible to easily cope with differences in axial thickness and radial dimensions of the plurality of split cores 18. Furthermore, the cooling function can be provided to the stator 10 without providing a cooling-dedicated part by providing the cooling function to the outer cylinder 20 that is an assembly part and allowing the coolant to flow through the outer cylinder 20. For this reason, although the stator 10 is provided with a cooling function, the installation space can be reduced without increasing the number of parts, and an excessive increase in cost can be prevented.

  Moreover, since the shape of the tube of the outer cylinder 20 is simple, unlike the case of making the outer cylinder 20 by performing press molding such as deep drawing on the plate material, the material yield can be greatly improved. In addition, although the case where the cross section of the outer cylinder 20 was a rectangle was demonstrated above, the cross section of the outer cylinder 20 can also be made into other shapes, such as a round shape and a triangle.

  FIG. 4 is a view corresponding to FIG. 3 and showing a first example of a rotating electrical machine stator of another example of the embodiment of the present invention. In the case of the first example of the other example shown in FIG. 4, instead of the outer cylinder 20 (FIG. 1 and the like) provided in the configuration of FIGS. A thin metal tube 36 is provided which is wound around. In the example shown in FIG. 4, the metal tube 36 has a round cross section. A refrigerant passage 37 is provided inside the metal pipe 36. Then, the metal tube 36 is wound around the outer periphery of the core body 24 constituted by the plurality of divided cores 18 arranged in an annular shape, and the portions of the metal tube 36 are bent radially outward at both ends. The portions near both ends and the outer peripheral surface of the core body 24 are welded and fixed simultaneously. In this case, the portions near both ends of the metal tube 36 may not face each other in the circumferential direction. In this case, welding of the portion near one end of the metal tube 36 and the outer peripheral portion of the core body 24 and the other end of the metal tube 36 are performed. Welding of the welded portions at a plurality of locations is performed simultaneously with the welding of the offset portion and the outer peripheral portion of the core body 24. In addition, the stator 10 is formed by winding the coil 16 around the teeth 14 constituting the stator core 12 in a state where the stator core 12 is constituted as described above.

  According to such a configuration, before assembling the metal tube 36, it is necessary to form the metal tube 36 in a flat shape so as to have substantially the same axial length as the axial direction (left-right direction in FIG. 4) of the core body 24. Disappears. Further, since the metal tube 36 is wound around the core body 24 for a plurality of turns, the winding turn can be changed according to the cross-sectional dimension of the metal tube 36. For this reason, it becomes easy to cope with the change in the overall axial length (thickness) of the stator 10 regardless of the cross-sectional dimension of the metal tube 36. Further, since the metal tube 36 is wound around the core body 24 a plurality of times, the flat metal tube is formed while maintaining or increasing the contact area between the core body 24 and the metal tube 36 and the heat radiation area to the outside of the metal tube 36. Since the flow rate can be increased with the same amount of refrigerant as in the case of flowing the refrigerant, the cooling efficiency can be improved, and the stagnation of the refrigerant in the metal tube 36, that is, the retention can be prevented. Other configurations and operations are the same as those in the embodiment shown in FIGS.

  In the first example of another example of FIG. 4, the cross section of the metal tube 36 is round. However, as in the second example and the third example of another example shown in FIGS. The cross section may be a rectangle such as a triangle, square, or rectangle. Thus, when the cross section of the metal tube 36 is triangular or rectangular, the contact area between the metal tube 36 and the core body 24 can be further increased, and the cooling efficiency can be improved.

  FIG. 7 is a view showing a stator core constituting a stator for a rotating electrical machine of a fourth example of another example of the embodiment of the present invention. In the stator core 12 of the fourth example of another example shown in FIG. 7, a pipe-like metal tube having a rectangular cross section is divided into a plurality of systems on the outer periphery of a core body 24 constituted by a plurality of divided cores 18 arranged in an annular shape. It is wrapped around. That is, in the example shown in FIG. 7, a first metal tube 38 having a rectangular cross section and a substantially semicircular shape is wound around one side portion (right side portion in FIG. 7) of the outer peripheral surface of the core body 24. A second metal tube 40 having a rectangular cross section and a substantially semicircular shape is wound around the other circumferential portion of the outer peripheral surface (the left portion in FIG. 7).

  In addition, the bent portions 42 are formed by bending the substantially opposite portions in the diametrical direction at the portions near both ends of the metal tubes 38 and 40 respectively outward in the radial direction. Further, the portions near one end of each of the metal tubes 38 and 40 are spaced apart from each other in the circumferential direction of the stator core 12, and the portions near the other end of each of the metal tubes 38 and 40 are spaced apart from each other so that the periphery of the stator core 12 is surrounded. Opposite to the direction.

  Then, the portions near the one ends of the first and second metal tubes 38, 40 and a part of the outer peripheral surface of the core body 24 in the circumferential direction, the portions near the other ends of the first and second metal tubes 38, 40, and Another portion of the outer peripheral surface of the core main body 24 and a portion on the substantially opposite side in the diametrical direction are welded and fixed simultaneously by the welded portions 44 and 46.

  Further, of both end portions of each of the metal pipes 38 and 40, one end portion facing upward is a refrigerant inlet 30 and the other end portion facing downward is a refrigerant outlet 32.

  According to the fourth example of such another example, the refrigerant can flow from the upper side to the lower side in each metal tube 38, 40, and the refrigerant does not circulate in an annular shape in each metal tube 38, 40. Refrigerant temperature can be reduced as compared with the case of circulating in an annular shape, and thermal deterioration of the refrigerant can be prevented. Further, since the refrigerant is not configured to circulate in an annular shape in each of the metal tubes 38 and 40, a refrigerant supply unit (not shown) having a cooling unit for cooling the refrigerant at the refrigerant inlet 30 of each of the metal tubes 38 and 40 during use. ), The refrigerant path does not have to be connected to the refrigerant outlet 32 of each of the metal pipes 38 and 40, and the refrigerant cooled by the refrigerant supply unit is continuously contained in each of the metal pipes 38 and 40. Can be injected and flushed. Further, the refrigerant can be ejected downward from the refrigerant outlet 32 of each of the metal pipes 38 and 40, and the refrigerant can be returned to the refrigerant supply unit from a refrigerant pool (not shown) received on the lower side by a pump or the like. Other configurations and operations are the same as those in the embodiment shown in FIGS. In addition, although the case where the cross section of the metal tubes 38 and 40 was a rectangle was demonstrated above, the cross section of the metal tubes 38 and 40 can also be made into other shapes, such as a round shape and a triangle.

  FIG. 8 is a view corresponding to FIG. 3 and showing a fifth example of the stator for a rotating electrical machine according to another example of the embodiment of the present invention. In the case of the fifth example of another example shown in FIG. 8, in the embodiment shown in FIGS. 1 to 3, the outer cylinder 20 a that is a metal tube is a core body 24 configured by a plurality of divided cores 18. Is formed so as to have a flat rectangular cross section having an outer shape along the axial direction. In addition, the refrigerant passage 29 is provided inside the outer cylinder 20a, and the axial direction (right and left in FIG. 8) is a direction orthogonal to the flow in the outer cylinder 20a at a plurality of circumferential positions on both axial end surfaces of the outer cylinder 20a. The refrigerant ejection holes 48 are formed in the direction).

  According to such a configuration, the refrigerant flowing inside the outer cylinder 20a is ejected to the outside through the refrigerant passage 29 from the refrigerant passage 29, and the ejected refrigerant is shown in the direction of arrow α in FIG. It is applied to each coil end 34 provided on both sides. For this reason, each coil end 34 can be directly cooled by the refrigerant without passing through the core body 24. Further, since the outer cylinder 20a is in contact with the outer peripheral surface of the core body 24, the core body 24 can also be cooled by the refrigerant flowing through the outer cylinder 20a. That is, according to this configuration example, the outer peripheral portion of the core body 24 and the coil 16 can be more effectively cooled by the refrigerant flowing through the outer cylinder 20a. Other configurations and operations are the same as those of the embodiment shown in FIGS.

  DESCRIPTION OF SYMBOLS 10 Stator, 12 Stator core, 14 teeth, 16 coils, 18 division | segmentation core, 20, 20a outer cylinder, 22 yoke element, 24 core main body, 26 bending part, 27 clearance gap, 28 welding part, 29 refrigerant path, 30 refrigerant inlet, 32 Refrigerant outlet, 34 Coil end, 36 Metal pipe, 37 Refrigerant passage, 38 First metal pipe, 40 Second metal pipe, 42 Bending part, 44, 46 Welding part, 48 Refrigerant ejection hole.

Claims (5)

A plurality of split cores arranged in an annular shape;
A metal tube wound around the outer periphery of the plurality of split cores,
A stator for a rotating electrical machine, wherein portions near both ends of a metal tube and the outer circumferences of a plurality of split cores arranged in an annular shape are welded and fixed simultaneously. The stator for a rotating electrical machine according to claim 1,
A stator for a rotating electrical machine, wherein a metal tube is formed in a rectangular cross section, and both end portions are welded and fixed at the same time in a state where the metal tube is rounded around the outer periphery of a plurality of divided cores. The stator for a rotating electrical machine according to claim 1,
The stator for a rotating electrical machine, wherein the metal tube is wound around the outer periphery of the plurality of divided cores by a plurality of turns. The stator for a rotating electrical machine according to claim 1,
The metal tube is a first metal tube wound around a circumferential one side portion of the outer periphery of the plurality of split cores,
Furthermore, it comprises a second metal tube wound around the other circumferential portion of the outer periphery of the plurality of split cores,
Parts near one end of both the first and second metal tubes and a part of the outer periphery of the plurality of split cores arranged in an annular shape, and parts near the other ends of the first and second metal tubes and an annular shape A stator for a rotating electrical machine, wherein another part of the outer periphery of the plurality of divided cores is welded and fixed simultaneously. The stator for a rotating electrical machine according to claim 1,
The metal tube has a flat rectangular cross section having an outer shape along the axial direction on the outer peripheral surfaces of the plurality of divided cores, and is formed on at least one axial end surface of the metal tube in a direction perpendicular to the flow in the metal tube. A stator for a rotating electrical machine having a refrigerant ejection hole.

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