JP2009225627A - Rotating electrical machine - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To suppress an increase in size of a housing by fixing a coil end of a stator coil, with an insulation distance between the coil end and the housing ensured at a target value. <P>SOLUTION: An electric motor 10 has the housing 11 consisting of a nearly cylindrical body portion 11a with one end opened and a lid portion 11b for covering the opening portion, with a stator 12 fixed inside of the body portion 11a. The stator 12 is equipped with a cylindrical stator iron core 14 with a plurality of teeth 14a provided at equal intervals on the inside and a coil 15 wound around the teeth 14a in a concentrated manner. An annular member 21 is positioned and fixed in contact with an end face of the stator iron core 14 and the housing 11, on the inside of the coil end 15a. The coil end 15a is fixed by a clip 22 after being positioned at a preliminarily set position with respect to the annular member 21. <P>COPYRIGHT: (C)2010,JPO&INPIT

Description

  The present invention relates to a rotating electrical machine including a stator in which a coil is wound around a cylindrical stator core having a plurality of slots, and a rotor provided inside the stator.

  In a rotating electric machine, when a coil end wound around a stator core is used in a free state, a bundle of coils is loosened and hinders, so that the coil end is fixed. Coil end fixing methods include fixing the coil end with a restraining thread, applying varnish, drying and fixing, using a self-bonding electric wire, and heating and fixing the wires to a certain temperature. There is a way.

  However, in the method using the restraint yarn, there is a possibility that the needle of the racing machine may damage the coil end when the restraint yarn is knitted using the racing machine. Moreover, in the method using a varnish, a man-hour is required for the varnish application work, and a drying furnace is required. Further, when recycling, i.e., discarding due to the life or failure of the rotating electrical machine, the coils are separated and copper is recovered. However, when varnish is used, the removal work is troublesome. In the method using the self-bonding electric wire, the wire diameter is increased by the amount of the adhesive, which is disadvantageous for downsizing of the rotating electrical machine and disadvantageous for recycling of the rotating electrical machine.

Then, the stator of the electric motor which fixed the coil end, without using restraint thread | yarn, a varnish, and a self-bonding electric wire is proposed (for example, patent document 1). In Patent Document 1, as shown in FIG. 7, a cylindrical stator core 72 provided with a plurality of slot openings 71 on an inner diameter portion is wound by a multi-pole coil (stator winding) 73. The stator is configured together with a wedge (a retaining member) 74. The stator forms an electric motor together with the rotor 75. An insulating resin member 76 having a curved coil end cover portion 76a that wraps around the coil end 73a along the shape of the coil end is disposed at the center of the coil end 73a of the coil 73, and the coil end 73a is fixed.
JP-A-10-126998

  In a rotating electrical machine, it is necessary to secure an insulation distance between the coil end of the stator and the housing. However, if the insulation distance is increased more than necessary, the housing needs to be enlarged correspondingly and the size is increased. With the coil end fixing method of Patent Document 1, it is possible to prevent the coil bundle from loosening. However, no consideration is given to the function of defining the insulation distance between the coil end and the housing, so in order to secure the insulation distance, a large distance between the coil end and the housing must be secured. There is a problem of increasing the size.

  The present invention has been made in view of the above-described conventional problems, and its purpose is to fix the coil end in a state in which the insulation distance between the coil end of the stator coil and the housing is secured to a target value. An object of the present invention is to provide a rotating electrical machine that can suppress an increase in size of a housing.

  In order to achieve the above object, the invention according to claim 1 is directed to a stator in which a coil is wound around a cylindrical stator core having a plurality of slots, and a rotation provided inside the stator. A rotating electric machine including a child. An annular member fixed inside the coil end of the coil wound around the stator core while being positioned in contact with the end face of the stator core and the housing; and the coil end is connected to the annular member. Coil end positioning and fixing means for fixing in a state of being positioned at a preset position. Here, the “annular member” is not limited to an annular member without a cut, but includes a cut, but also includes a piece that is in a state where the ends are in contact with each other and are apparently not cut.

  In the present invention, an annular member fixed in a state of being positioned in contact with the end face of the stator core and the housing exists inside the coil end, and the coil end is fixed to the annular member by the coil end positioning fixing means. And fixed at a preset position. Therefore, the coil end can be fixed in a state in which the distance between the coil end and the housing is ensured to a target value, and the enlargement of the housing can be suppressed.

  According to a second aspect of the present invention, in the first aspect of the present invention, the coil end positioning and fixing means is formed integrally with the annular member. In the present invention, the number of parts can be reduced as compared with the configuration in which the coil end positioning and fixing means is formed separately from the annular member.

  A third aspect of the present invention is the clip according to the first aspect, wherein the coil end positioning and fixing means includes a locking portion that is locked to a locking hole formed in the annular member. . In the present invention, the configuration of the annular member is simplified as compared with the configuration in which the coil end positioning and fixing means is formed integrally with the annular member.

  According to a fourth aspect of the present invention, in the invention according to any one of the first to third aspects, a coolant can be supplied to the housing from above the coil end toward the coil end. A coolant passage is formed. In this invention, when the rotating electric machine is driven, when the cooling liquid is supplied to the cooling liquid passage formed in the housing, the cooling liquid drops or flows down from the upper end of the coil end toward the coil end, thereby cooling the coil end. Is done. At that time, since there is an annular member inside the coil end, even if the coil is concentrated winding, the cooling liquid that has cooled one coil end does not fall as it is, but passes through the annular member to the next coil end. And moves downward along the coil end. That is, the coolant that has flowed down from the coolant passage to the coil end moves downward while sequentially cooling the coil end. Therefore, the coil end can be efficiently cooled.

  The invention according to claim 5 is the invention according to any one of claims 1 to 4, wherein the annular member includes a cylindrical portion disposed inside the coil end and one end of the cylindrical portion. It is formed in the shape provided with the collar part formed so that it may protrude outside. In the present invention, the annular member is positioned in a state in which the annular member is in contact with the end face of the stator core and the housing in a stable state as compared with the case where the annular member is a cylinder.

  According to the present invention, the coil end can be fixed in a state in which the insulation distance between the coil end of the stator coil and the housing is ensured to a target value, and the increase in size of the housing can be suppressed.

(First embodiment)
Hereinafter, a first embodiment in which the present invention is embodied in an electric motor in which a coil is wound in concentrated winding will be described with reference to FIGS. 1 and 2.

  As shown in FIG. 1 (a), an electric motor 10 as a rotating electrical machine has a housing 11 composed of a substantially cylindrical main body portion 11a with one end opened and a lid portion 11b covering the opening. A stator (stator) 12 is fixed inside the portion 11a. The lid portion 11b is fastened and fixed to the main body portion 11a by a bolt 13 that is screwed into a screw hole formed in the main body portion 11a.

  The stator 12 is formed of laminated electromagnetic steel plates and is cylindrical and has a stator core 14 in which a plurality of teeth 14a are provided at equal intervals, and a coil (winding) 15 wound around the teeth 14a. In order to prevent the coil 15 from coming off from the slot between the teeth 14a, a wedge 16 covering the end of the slot is formed. The wedge 16 is formed of insulating paper. The coil 15 is shown only in the coil end 15a. The coil 15 is wound by concentrated winding.

  An inner peripheral surface portion 11c having the same diameter as the outer diameter of the stator core 14 is formed in the main body portion 11a so as to have the same length as the stator core 14, and is open end side (left side in FIG. 1) from the inner peripheral surface portion 11c. Is formed so as to gradually increase in diameter from the end portion of the inner peripheral surface portion 11c, and the back side (right side in FIG. 1) is formed to have a smaller diameter than the inner peripheral surface portion 11c, and one end of the stator core 14 is formed. Is in contact with the step portion 11d.

  On the wall 11e opposite to the opening side of the main body portion 11a, a boss portion 17 projects from the inside of the central portion. The boss portion 17 is formed in a substantially truncated cone shape having a diameter smaller than the inner diameter of the stator core 14, and a concave portion 17 a is formed in the central portion. A rotor (rotor) 18 is disposed inside the stator 12. The rotor 18 is rotatably supported with respect to the housing 11 via a bearing 20a in which the rotation shaft 19 is fixed to the recess 17a and a bearing 20b fixed to the approximate center of the lid portion 11b. The rotating shaft 19 is provided so as to penetrate the lid portion 11b. In the present embodiment, the rotor 18 includes a permanent magnet and constitutes a permanent magnet motor.

  In the housing 11, the annular member 21 is fixed inside the coil end 15 a of the coil 15 wound around the stator core 14 in a state of being positioned in contact with the end surface of the stator core 14 and the housing 11. Yes. The annular member 21 is disposed on both sides of the stator core 14 so as to sandwich both end surfaces of the teeth 14a.

  As shown in FIGS. 1C and 2A, the annular member 21 includes a cylindrical portion 21a and a plurality of protrusions 21b formed so as to extend a part of the cylindrical portion 21a from one end of the cylindrical portion 21a. It consists of and. The protrusions 21b are formed at equal intervals in the circumferential direction of the cylindrical portion 21a and narrower than the width of the end surface of the teeth 14a so as to be able to come into contact with the end surface of the teeth 14a.

  In the cylindrical portion 21a, a pair of locking holes 23a and 23b for attaching a clip 22 as a coil end positioning and fixing means is formed at a position corresponding to each protrusion 21b. As shown in FIG. 2B, the clip 22 is formed in a substantially U shape, penetrates the locking holes 23a and 23b, and has a locking protrusion 24a at the tip, A pair of locking pieces 25 that are formed on both sides of the locking portion 24 and shorter than the locking portion 24 are provided. The locking piece 25 is configured such that the locking portion 24 penetrates the locking holes 23a and 23b and the locking projection 24a is in contact with the inner surface of the cylindrical portion 21a. It is formed so as to contact the outer surface. That is, the clip 22 includes a locking portion 24 that is locked to locking holes 23 a and 23 b formed in the annular member 21. The annular member 21 and the clip 22 are formed of a material having electrical insulation, and the clip 22 needs to have flexibility. In this embodiment, both are formed of resin.

  The positions of the locking holes 23a and 23b are such that the clip 22 is positioned on the coil end 15a that protrudes from the end surface of the stator core 14 so as to straddle the teeth 14a when the protrusion 21b of the annular member 21 is in contact with the teeth 14a. It is set to a position that is fixed in a state where it is positioned at a preset position with respect to the annular member 21. Specifically, as shown in FIG. 1B, the insulation distance L1 in the axial direction of the stator 12 of the coil end 15a fixed by the clip 22 attached to the annular member 21 on the back side of the housing 11 is This is the distance between the end surface of the cylindrical portion 21a in contact with the wall 11e and the inner surface of the engaging portion 24 of the clip 22 located on the wall 11e side. Further, the insulation distance L2 in the radial direction of the stator 12 of the coil end 15a is the distance between the inner wall surface of the main body 11a and the inner surface of the clip 22.

  Near the opening end of the housing 11, the insulation distance in the axial direction of the stator 12 of the coil end 15a fixed by the clip 22 attached to the annular member 21 is the same as the end surface of the cylindrical portion 21a in contact with the lid portion 11b. The distance from the inner surface of the locking portion 24 of the clip 22 located on the lid portion 11b side. The insulation distance of the coil end 15 a in the radial direction of the stator 12 is the distance between the inner wall surface of the main body 11 a and the inner surface of the clip 22.

Next, a method for assembling the electric motor 10 configured as described above will be described.
As shown in FIG. 2A, with respect to the stator core 14 to which the coil 15 and the wedge 16 are attached, the annular member 21 is disposed inside the coil end 15a in a state where the projection 21b abuts on the teeth 14a. . In this state, the clip 22 is fixed to the locking holes 23a and 23b in such a state that the center portion of the coil end 15a is sequentially sandwiched. And after arrange | positioning the annular member 21 to the coil end 15a of the both sides of the stator core 14, the stator core 14 is inserted in the main-body part 11a.

  Next, the rotor 18 is inserted inside the stator core 14 with the bearings 20a and 20b fitted and fixed at predetermined positions of the rotary shaft 19, and the bearing 20a fitted and fixed to one end of the rotary shaft 19 is inserted. The lid portion 11b is fixed to the main body portion 11a with the bolt 13 in a state where the concave portion 17a of the boss portion 17 is fitted and the other bearing 20b is fitted to the lid portion 11b. When the bolt 13 is tightened with a predetermined torque, the end surface of the annular member 21 disposed on the back side of the housing 11 is on the wall 11e, the tip of the stator core 14 is on the step 11d of the main body 11a, and the opening of the housing 11 is opened. The end face of the annular member 21 arranged on the side is fixed in a state where it abuts against the lid portion 11b, and the assembly is completed.

  Since the insulation distance between the coil end 15a and the housing 11 is determined by the length of the annular member 21 and the positions of the locking holes 23a and 23b, it is avoided that the insulation distance varies depending on the operator. Therefore, it is possible to secure the necessary insulation distance without setting a larger insulation distance in anticipation of variations in the insulation distance by the operator.

According to this embodiment, the following effects can be obtained.
(1) Inside the coil end 15a of the coil 15 wound around the stator core 14, an annular member 21 fixed in a state of being positioned in contact with the end surface of the stator core 14 and the housing 11, and the coil end Coil end positioning fixing means (clip 22) for fixing 15a in a state where it is positioned at a preset position with respect to the annular member 21 is provided. Therefore, the coil end 15a is fixed in a state of being positioned at a preset position with respect to the annular member 21 by the coil end positioning fixing means. Therefore, the coil end 15a can be fixed in a state in which the distance between the coil end 15a and the housing 11 is ensured to a target value, and the enlargement of the housing 11 can be suppressed. Further, since no varnish or adhesive is required to fix the coil end 15a, it is possible to reduce the effort for separating the coils during recycling.

  (2) The coil end positioning and fixing means is a clip 22 having a locking portion 24 that is locked to locking holes 23 a and 23 b formed in the annular member 21. Therefore, the configuration of the annular member 21 is simplified as compared with the configuration in which the coil end positioning and fixing means is integrally formed with the annular member 21.

  (3) Since the annular member 21 is composed of the cylindrical portion 21a and a plurality of protrusions 21b continuous to the cylindrical portion 21a, the annular member 21 may be formed in a tapered shape or provided with a flange portion, or a large diameter portion and a small diameter portion. The configuration is simple compared to a shape in which is continuous through a stepped portion.

  (4) When attaching the clip 22 to the cylindrical portion 21a, when the locking projection 24a passes through the locking holes 23a and 23b and the locking holes 23a and 23b pass while the locking portion 24 is bent. A sound is generated when the flexure is eliminated and comes into contact with the locking holes 23a and 23b, and it can be confirmed by hearing that the clip 22 is attached at a predetermined position. Further, when the clip 22 is attached at a predetermined position, the bending of the locking portion 24 is eliminated, so that it can be visually confirmed whether or not the clip 22 is attached at the predetermined position.

(Second Embodiment)
Next, a second embodiment will be described with reference to FIGS. This embodiment is different from the first embodiment in that the cooling oil (cooling liquid) for cooling the coil end 15a can be dropped or flowed down from above the coil 15. The same parts as those of the first embodiment are denoted by the same reference numerals, and detailed description thereof is omitted.

  As shown in FIG. 3, a coolant passage 30 extending in the axial direction is formed on the upper portion of the main body 11 a and corresponds to the upper side of the coil end 15 a having one end opened on the lid 11 b side and the other end on the back side. It is formed to extend to a position. The coolant passage 30 includes supply holes 30a and 30b formed at positions facing the coil end 15a on the back side and the opening side of the main body 11a. A hole 31 communicating with the open end of the coolant passage 30 is formed in the lid portion 11b. Then, the cooling oil RO supplied from the outside to the cooling fluid passage 30 through the hole 31 from the pipe 32 that guides the cooling oil RO discharged from an external pump (not shown) to the coil end from the supply holes 30a and 30b. It drops or flows down toward 15a.

  In addition, in the lower part (bottom part) of the main body part 11a, a stay part that is supplied into the housing 11 from the supply holes 30a and 30b and that the cooling oil RO that has reached the bottom part through the coil end 15a joins and temporarily stays. 33 is provided. Further, a pipe 34 for pumping out the cooling oil RO staying in the stay portion 33 is provided in the cover portion 11b in a state of penetrating the cover portion 11b. The pipe 34 is connected to a pipe line communicating with an intake port of an external pump (not shown).

  In this embodiment, when the electric motor 10 is driven, the pump provided outside the electric motor 10 is also driven, and the cooling oil RO is supplied to the cooling fluid passage 30 and the main body portion via the supply holes 30a and 30b. It is supplied into the main body 11a from above the coil end 15a located on the back side and the opening side of 11a. When the annular member 21 does not exist, as shown in FIG. 4B, the cooling oil RO supplied from the supply holes 30a and 30b is disposed so as to be positioned at the top of the plurality of coil ends 15a. It falls on the coil end 15a and moves downward along the surface of the coil end 15a. And the ratio which falls below as it is, without cooling the adjacent coil end 15a increases.

  However, when the annular member 21 is present, the cooling oil RO falls on the coil end 15a arranged so as to be positioned at the uppermost part, moves downward along the surface of the coil end 15a, and the annular member 21 21 and moves onto the adjacent coil end 15a. Then, it sequentially moves onto the adjacent coil end 15 a and reaches the staying portion 33.

Therefore, according to this 2nd Embodiment, in addition to the effect of (1)-(4) of 1st Embodiment, the following effects can be acquired.
(5) The housing 11 is formed with a coolant passage 30 including supply holes 30a and 30b through which the cooling oil RO can be supplied from above the coil end 15a toward the coil end 15a. Therefore, in combination with the presence of the annular member 21, even when the coil 15 is concentrated winding, the cooling oil RO that has cooled one coil end 15a does not fall as it is, but cools the coil end 15a sequentially. However, since it moves downward, the coil end 15a can be efficiently cooled.

The embodiment is not limited to the above, and may be embodied as follows, for example.
The coil end positioning and fixing means is not limited to the configuration formed separately from the annular member 21, and may be formed integrally with the annular member 21. For example, as shown in FIG. 5A, a locking piece 26 as a coil end positioning fixing means may be provided in a folded shape on the opposite side of the projection 21b of the cylindrical portion 21a. The locking piece 26 includes an engaging portion 26a having a substantially U-shaped cross section so that the center portion of the coil end 15a can be held. In this case, the number of parts can be reduced as compared with a configuration in which the coil end positioning and fixing means is formed separately from the annular member 21.

  The coil end positioning and fixing means formed integrally with the annular member 21 is not limited to one formed by bending a part of the annular member 21. For example, as shown in FIG. 5B, after the locking piece 26 having the engagement portion 26a having a substantially U-shaped cross section is formed separately from the annular member 21, it is fixed to the annular member 21 with an adhesive. May be formed.

  The clip as a coil end positioning and fixing means formed separately from the annular member 21 is limited to a configuration including a pair of locking portions 24 locked to the locking holes 23a and 23b formed in the annular member 21. Absent. For example, as shown in FIG. 5C, the annular member 21 is provided with a recess 21c at a position opposite to the protrusion 21b. And as shown in FIG.5 (d), the latching | locking part 24 latched by the one latching hole 23a formed in the annular member 21 and the latching piece 27 latched by the recessed part 21c are provided. The clip 28 may be configured as described above.

  The annular member 21 is not limited to the shape in which the end surface of the cylindrical portion 21 a having a constant diameter disposed inside the coil end 15 a is in contact with the main body portion 11 a of the housing 11. For example, as shown to Fig.6 (a), even if formed in the shape provided with the collar part 21d formed in the end of the cylindrical part 21a arrange | positioned inside the coil end 15a so that it might protrude outside. Good. In this case, as compared with the case where the annular member 21 is a cylinder, the annular member 21 is positioned in a state in which the annular member 21 is in contact with the end surface of the stator core 14 and the housing 11 in a stable state.

  As shown in FIG. 6B, the annular member 21 has a shape in which a cylindrical portion 21a and a small-diameter portion 21e having a smaller diameter than the cylindrical portion 21a are continuous via a stepped portion. Then, the coil end 15a may be fixed to the annular member 21 by a coil end positioning fixing means (not shown) in a state where the coil end 15a is bent toward the small diameter portion 21e.

The shape of the annular member 21 may be an outer truncated cone shape that gradually decreases in diameter from the side facing the end face of the stator core 14.
As a coil end positioning and fixing means for fixing the coil end 15a to the annular member 21, a binding band having a serrated locking portion for preventing loosening and a hole through which the serrated locking portion is inserted is used. Also good.

  ○ The annular member 21 is not limited to an annular member without a cut, but has a cut, but even when the end is in contact with each other in a state of being fixed to the housing 11, it is a member that is apparently unbroken. Good. When this annular member is applied to a configuration in which the cooling oil is dropped or flowed down from above the coil as in the second embodiment, the annular member may be arranged so that the cut line is on the lower side (bottom).

O The material of the annular member 21 is not limited to resin, but may be an insulating layer formed on the surface of a metal plate.
The coil 15 is not limited to concentrated winding, and may be distributed winding.

The number of the teeth 14a of the stator 12 is not limited to 6, and may be any number, and may be appropriately changed to 5 or less or 7 or more depending on the size of the stator core 14.
The stator core 14 may be circular and the inner side is almost circular, and the outer shape does not have to be circular.

O It is good also as a structure which drives the pump for supplying a cooling fluid to the cooling fluid channel | path 30 of the coil end 15a with the rotating shaft of an electric motor.
(Circle) not only the both sides of the stator core 14 but the annular member 21 may be arrange | positioned only at one side.

○ It may be applied not only to motors but also to generators.
○ The present invention is not limited to permanent magnet motors, and may be applied to induction motors, reluctance motors, and the like.

The following technical idea (invention) can be understood from the embodiment.
(1) In the invention according to claim 4, the coil is wound around the fixed iron core by concentrated winding.

1A is a schematic sectional view of a rotating electrical machine, FIG. 1B is a partially enlarged view of FIG. 1A, and FIG. 1C is a schematic perspective view of a stator. (A) is a disassembled perspective view of a stator, (b) is a perspective view of a clip. The schematic cross section of the rotary electric machine in 2nd Embodiment. (A) is a schematic perspective view explaining the effect | action when cooling oil is dripped, (b) The schematic perspective view explaining the effect | action when an annular member does not exist. (A), (b) is a fragmentary sectional view which shows the coil end positioning fixing means integrally formed with the annular member, (c) is a partial schematic diagram of the annular member of another embodiment, (d) is also a clip. The partial model perspective view of an annular member. (A), (b) is a perspective view which shows the annular member of another embodiment, respectively. The schematic cross section which shows the fixed state of the coil end of a prior art.

Explanation of symbols

  RO: Cooling oil as coolant, 11 ... Housing, 12 ... Stator, 14 ... Stator core, 15 ... Coil, 15a ... Coil end, 18 ... Rotor, 21 ... Ring member, 21a ... Cylindrical part, 21d ...鍔 part, 22, 28 ... clip, 23a, 23b ... locking hole, 24 ... locking part, 26, 27 ... locking piece as coil end positioning fixing means, 30 ... coolant passage.

Claims (5)

A rotating electrical machine comprising a stator in which a coil is wound around a cylindrical stator iron core having a plurality of slots, and a rotor provided inside the stator,
An annular member fixed inside the coil end of the coil wound around the stator core and positioned in contact with the end surface of the stator core and the housing; and
A rotating electric machine comprising: a coil end positioning and fixing unit that fixes the coil end in a state where the coil end is positioned at a preset position with respect to the annular member.   The rotating electrical machine according to claim 1, wherein the coil end positioning and fixing means is formed integrally with the annular member.   2. The rotating electrical machine according to claim 1, wherein the coil end positioning and fixing means is a clip including a locking portion that is locked in a locking hole formed in the annular member.   The rotating electrical machine according to any one of claims 1 to 3, wherein a cooling fluid passage capable of supplying a cooling fluid from above the coil end toward the coil end is formed in the housing.   The said annular member is formed in the shape provided with the cylindrical part arrange | positioned inside the said coil end, and the collar part formed so that it might protrude outside at the end of the said cylindrical part. The rotating electrical machine according to any one of 4.

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