JP2011259594A - Stator of rotary electric machine - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a stator of a rotary electric machine having an improved mechanical strength than before, with no increase in a manufacturing cost with the conventional number and weight of the members.SOLUTION: A stator of a rotary electric machine includes a cylindrical stator holder 2, a core which is fitted in the inner peripheral surface of the stator holder 2, and a coil that is wound on the core. The stator holder 2 includes a cylinder part 4 which is formed by bending in cylinder a metal square sheet around axial line to be extended in the axial line direction, which is then abutted with each other, and welding two side edges 41 and 45 of the square sheet, for fitting and holding the core; an attaching part 5 which is formed by cutting an end part of the cylinder part 4 out of a flange part having been bent and extended in radial direction, to be extended over both ends of a welding part 49, and being protruded from the cylinder part 4 in radial direction; and a pedestal member 6 which is attached with a terminal stage to electrically connect the coil to the outside, and is secured to the attaching part 5 by a fixing part (fixing holes 55 and 56) formed on both sides on the welding part 49.

Description

  The present invention relates to a stator for a rotating electrical machine, and more particularly to an improvement in the mechanical strength of the stator.

  In a rotating electric machine such as a generator motor mounted on a hybrid vehicle or an electric vehicle, an inner rotor rotating magnet type in which a stator having a coil is arranged on the outer peripheral side and a rotor having a magnet is arranged on the inner peripheral side is often used. ing. In a stator of this type of rotating electrical machine, conventionally, a stator core is formed by laminating laminated materials formed by punching electromagnetic steel sheets or the like in an annular shape. Since an annular laminated material has a low yield, it has become common to use a split core in which laminated materials divided in the circumferential direction at equal central angles are laminated. The plurality of split cores are fitted to the inner peripheral surface of the cylindrical stator holder by an integration technique such as press fitting or shrink fitting. In these integrated technologies, first, both are manufactured separately so that the inner diameter of the stator holder is slightly smaller than the outer diameter of the split core. In press-fitting, an external force is applied to forcibly push the split core into the stator holder, and both are integrally formed. In shrink fitting, the stator holder is heated and expanded, and after the split cores are accommodated, the stator holder is cooled and contracted, and both are integrally formed.

  An example of an AC motor composed of a stator using a split core is disclosed in Patent Document 1. The AC motor used in the hybrid vehicle drive device of Patent Document 1 includes a stator configured by arranging a plurality of stator pieces (divided cores) in a ring shape, and a stator holding ring (stator holder) to which the stator is press-fitted and fixed. It has. In general, the stator holder is not limited to Patent Document 1, and the stator holder has a cylindrical shape, and various dimensions such as an inner diameter and a wall thickness are appropriately designed according to the size of the split core and the required mechanical strength. Therefore, standard steel pipes with standard dimensions cannot be used, and a stator holder is often manufactured by bending a metal rectangular plate into a cylindrical shape and welding two edges that are in contact with each other.

Japanese Patent No. 3666727

  By the way, when the split core is fitted to the inner peripheral surface of the stator holder by press fitting or shrink fitting, the stator holder is deformed by an outward expansion force acting in the radial direction. At this time, if the mechanical strength of the welded portion of the stator holder is not sufficient, the welded portion becomes a weak point and the stator may be damaged. In addition, since the load, vibration, impact, etc. act repeatedly not only at the time of manufacture but also at the time of using the rotating electrical machine, it is necessary to maintain the mechanical strength of the stator for a long period of time. It is natural that the mechanical strength can be improved by adding a reinforcing material to the welded part of the stator holder or increasing the wall thickness. This increases the weight and further increases the number of manufacturing steps, resulting in an increase in cost.

  The present invention has been made in view of the above-mentioned problems of the background art, and provides a stator for a rotating electrical machine that has improved mechanical strength as compared with the prior art without increasing the manufacturing cost with the conventional number of members and weight. Is a problem to be solved.

  The stator of the rotating electrical machine according to claim 1 that solves the above-described problem includes a cylindrical stator holder, a core that is fitted to the inner peripheral surface of the stator holder, and a coil that is wound around the core. In the stator of the rotating electrical machine, the stator holder is welded to two edges of the rectangular plate material in which a metal rectangular plate material is bent into a cylindrical shape around the axis and extends in the axial direction to contact each other. A cylindrical portion that is formed and held by fitting the core; and an end portion of the cylindrical portion is formed by being cut out from a flange portion that is bent and extended in the radial direction, and extends across both sides of the welded portion. And a base member fixed to the mounting portion by fixing portions formed on both sides of the welded portion, and a mounting base that is electrically connected to the outside is mounted. Characterized in that it has a.

  The invention according to claim 2 is characterized in that, in claim 1, the two side edges of the rectangular plate member have fitting portions that fit together.

  In the stator of the rotating electrical machine according to claim 1, the stator holder includes a cylindrical portion formed by bending a metal rectangular plate material into a cylindrical shape and welding two edges, and an end portion of the cylindrical portion. It has the attachment part extended over the both sides of a welding part, and the base member fixed to the attachment part by the fixing part formed in the both sides of a welding part. That is, the pedestal member fixed across the two original edges of the welded portion reinforces the welded portion and improves the mechanical strength. The pedestal member is a member conventionally used for attaching the terminal block, and can also serve as a reinforcing material for the welded portion. Therefore, the mechanical strength of the stator can be improved as compared with the prior art without increasing the manufacturing cost with the conventional number of members and the weight of the members.

  In the invention which concerns on Claim 2, the two edge of the rectangular board material which is the raw material of a cylindrical part has a fitting part which fits mutually. For this reason, when a rectangular plate material is bent into a cylindrical shape, the two edges are brought into contact with each other while being fitted in the fitting portion, and welding is performed including the fitting portion. Therefore, the fitting portion reinforces the welded portion in cooperation with the above-described base member, and the mechanical strength of the stator can be further improved.

It is the top view seen from the axis line extension direction explaining the structure of the rotary electric machine which implements the present invention typically. It is a perspective view explaining the shape of the stator holder in embodiment. It is sectional drawing which looked at the attaching part vicinity of the stator of embodiment from the outer peripheral side.

  A stator of a rotating electrical machine according to an embodiment of the present invention will be described with reference to FIGS. FIG. 1 is a plan view seen from the direction in which the axis AX extends, schematically explaining the structure of a rotating electrical machine 9 embodying the present invention. The rotating electrical machine 9 is configured to be substantially axially symmetric about the axis AX, and the rotor 91 is disposed on the coaxial inner side, and the stator 1 is disposed on the coaxial outer side. The rotor 91 has a substantially cylindrical shape, and is formed by laminating thin annular magnetic steel plates in the front and back direction in FIG. In addition, a plurality of permanent magnets (not shown) are embedded so that N poles and S poles are alternately arranged in the circumferential direction on the outer peripheral side of the rotor 91.

  The stator 1 according to the embodiment includes a cylindrical stator holder 2 and a core 3 fitted to the inner peripheral surface of the stator holder 2 by shrink fitting. The core 3 is configured by arranging 20 divided cores 31 in a ring shape in the illustrated example. Each of the split cores 31 is formed by laminating thin electromagnetic steel plates in the front and back direction of the paper, and has unillustrated magnetic pole teeth extending inward in the radial direction. A conductor is wound around each magnetic pole tooth to form a coil (not shown).

  The stator holder 2 includes a cylindrical portion 4, an attachment portion 5, a pedestal member 6 (shown by a broken line in FIGS. 1 and 2) and the like. FIG. 2 is a perspective view for explaining the shape of the stator holder 2. The cylindrical part 4 and the attachment part 5 are formed from a rectangular plate material made of metal.

  More specifically, a metal rectangular plate is first bent into a cylindrical shape around the axis AX. Next, the two edges 41 and 45 extending in the direction of the axis AX and in contact with each other are welded to form the cylindrical portion 4. The two side edges 41 and 45 have a fitting part. That is, a convex fitting portion 42 having a substantially isosceles trapezoidal shape is formed in advance on one of the edges 41 so that the tip side protrudes narrowly on the base side. A concave fitting portion 46 into which the convex fitting portion 42 is fitted is formed on the other edge 45 in advance. The convex fitting part 42 and the concave fitting part 46 are fitted to each other prior to welding. The two edges 41, 45 are welded including the convex fitting part 42 and the concave fitting part 46, thereby forming the cylindrical part 4. A portion where the two edges 41 and 45 are joined by welding is a welded portion 49.

  Next, one end portion of the cylindrical portion 4 is bent and extended in the radial direction to form a flange portion. The attachment part 5 is cut out and formed from the part over the both sides of a welding part among flange parts. As shown in FIGS. 1 and 2, the attachment portion 5 is composed of three parts: a central attachment portion 51, one attachment portion 52, and the other attachment portion 53. The central attachment portion 51 extends in the circumferential direction over both sides of the welded portion 49 and protrudes outward in the radial direction from the cylindrical portion 4. On the other hand, the attachment portion 52 is formed so as to protrude outward in the radial direction from the one edge 41 side. Similarly, the other attachment portion 53 is formed so as to protrude radially outward from the other edge 42 side. The one attachment portion 52 and the other attachment portion 53 are respectively provided with fixing holes 55 and 56 corresponding to the fixing portion of the present invention.

  A common plane is formed on the upper surfaces of the central, one and other attachment portions 51, 52, 53 in the drawing. Further, between the center mounting portion 51 and the one mounting portion 52, one clamping portion 57 that clamps the hexagonal head of the bolt in a non-rotatable manner is formed, and also between the central mounting portion 51 and the other mounting portion 53. The other clamping part 58 is formed.

  In addition, mounting flanges 81, 82, 83 extending outward in the radial direction are cut out and formed at three locations of the flange portion. Fixing holes 811 and 821 and positioning holes 812 and 822 are formed in the two mounting flanges 81 and 82, respectively, and only the fixing hole 831 is formed in the third mounting flange 83. The positioning holes 812 and 822 are for determining the assembly position when the stator 1 is assembled to an unillustrated case, and the fixing holes 811, 821 and 831 are for fixing the stator 1 to the case. Furthermore, a narrow outer peripheral rib 84 is formed over the entire circumference except for the attachment portion 5 and the attachment flanges 81, 82, 83. The outer peripheral rib 84 is for improving the strength of the end portion of the stator holder 2.

  The bending and extending process of the end of the cylindrical part 4 and the cutting process of the flange part can be performed by press molding, for example, and are not limited thereto.

  FIG. 3 is a cross-sectional view of the vicinity of the attachment portion 5 of the completed stator 1 as viewed from the outer peripheral side. As shown in the figure, the base member 6 is fixed to the attachment portion 5. Specifically, the pedestal member 6 is substantially rectangular as shown in FIGS. 1 and 2, and is formed based on a steel plate material. The base member 6 is formed with bag-hole-like tightening holes 61 and 62 having female threads corresponding to the positions of the two fixing holes 55 and 56 on the attachment portion 5 side. In addition, fixing holes 63 and 64 penetrating the base member 6 are formed corresponding to the positions of the one clamping part 57 and the other clamping part 58 on the attachment part 5 side. Then, as shown in FIG. 3, two pedestal fixing bolts 67 and 68 are respectively inserted from below in the drawing of the two fixing holes 55 and 56 on the attachment portion 5 side, and the tightening holes 61 of the pedestal member 6 are inserted. , 62. The lengths of the base fixing bolts 67 and 68 are set to appropriate lengths that can be accommodated in the tightening holes 61 and 62. Thereby, the base member 6 is placed and fixed on the upper surface in the drawing of the center, one and the other attachment portions 51, 52, 53.

  The base member 6 is fixed before the core 3 is shrink-fitted into the stator holder 2. Thereby, the base member 6 also serves as a reinforcing material that improves the mechanical strength of the welded portion 49 of the stator holder 2. That is, the welded portion 49 is reinforced in cooperation with the convex and concave fitting portions 42 and 46 against the radially outward expansion force applied to the stator holder 2 during shrink fitting. In addition, the effect | action which the base member 6 and the convex and concave fitting parts 42 and 46 reinforce the welding part 49 becomes effective also with respect to the repeated load, vibration, and impact at the time of use.

  After the core 3 is fitted to the stator holder 2, the terminal block 7 is placed on the base member 6 and fixed. As shown in FIG. 3, fixing holes 71 and 72 penetrating through the bottom surface are formed in the resin terminal block 7 corresponding to the positions of the one clamping part 57 and the other clamping part 58 on the attachment part 5 side. Has been. Then, the two terminal block fixing bolts 73 and 74 are respectively inserted into the one clamping part 57 and the other clamping part 58 on the attachment part 5 side from below in the figure, and the hexagonal head parts 731 and 741 are clamped so as not to rotate. . The shaft portions 732 and 742 of the terminal block fixing bolts 73 and 74 pass through the fixing holes 63 and 64 of the base member 6 and the fixing holes 71 and 72 of the terminal block 7 and reach the inside of the terminal block 7. On the inner side of the terminal block 7, the two fixing nuts 75 and 76 are screwed into the shaft portions 732 and 742 of the fixing bolts 73 and 74, respectively, and tightened. Thereby, the terminal block 7 is fixed to the base member 6. Thereafter, the coil is electrically connected to the outside using the terminal block 7.

  In the present embodiment, the pedestal member 6 is a member conventionally used for attaching the terminal block 7 and can also serve as a reinforcing material for the welded portion 49. Therefore, the mechanical strength of the stator 1 can be improved as compared with the conventional one without increasing the manufacturing cost with the conventional number of members and the weight of the members.

1: Stator
2: Stator holder 3: Core 31: Divided core 4: Cylindrical part 41: Edge 42: Convex fitting part 45: Edge 46: Concave fitting part 49: Welding part 5: Attachment part 51: Center attachment part 52: One attachment part 53: The other attachment part 55, 56: Fixing hole (fixing part) 57: One clamping part 58: The other clamping part 6: Base member 61, 62: Clamping hole 63, 64: Fixing hole 67, 68: Base Fixing bolt 7: Terminal block 71, 72: Fixing hole 73, 74: Terminal block fixing bolt 75, 76: Fixing nut 81, 82, 83: Mounting flange 84: Outer peripheral rib 9: Rotating electric machine

Claims (2)

In a stator of a rotating electrical machine comprising a cylindrical stator holder, a core fitted to the inner peripheral surface of the stator holder, and a coil wound around the core,
The stator holder is formed by welding a metal rectangular plate material that is bent into a cylindrical shape around an axis and welding the two edges of the rectangular plate material that extend in the axial direction and contact each other. A cylindrical part to be fitted and held;
An attachment portion that is formed by cutting an end portion of the cylindrical portion from a flange portion that is bent and extended in a radial direction, extends over both sides of the welding portion, and protrudes in a radial direction from the cylindrical portion;
A terminal block for electrically connecting the coil to the outside is attached, and a pedestal member fixed to the attachment portion by fixing portions formed on both sides of the weld portion,
A stator for a rotating electrical machine, comprising:   2. The stator of a rotating electrical machine according to claim 1, wherein the two side edges of the rectangular plate member have fitting portions that are fitted to each other.

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