JP2001292548A - Stator of rotating electric machine - Google Patents

Abstract

PROBLEM TO BE SOLVED: To shorten the length of a coil end part by a large extent. SOLUTION: A straight flat wire is formed into a U shape in advance, the two sides of a straight line are inserted into slots that are adjacent, while sandwiching stator gear teeth, and both edges of the inverted U-shaped side of a coil are connected with a thin plate rod-shaped piece, thus forming the coil to achieve a one-turn closed circuit. By making an inverted U-shaped side end face for obtaining a stator coil for forming a prescribed number of turns, the thin plate rod-shaped pieces overlap for connecting by inserting the plurality of coils, and by connecting both edges of the inverted U-shaped side, the plate thickness at a part where the both are overlapped is reduced by half, so that the thickness corresponding to the plate thickness of a flat-square wire coil is achieved, when both of them are overlapped.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a stator for a rotating electric machine, and more particularly to a stator suitable for a synchronous machine.

[0002]

2. Description of the Related Art As shown in FIG. 21, a stator of a rotary electric machine such as a synchronous machine generally has teeth 3a arranged in a circumferential direction and slots 3 existing between the teeth.
After mounting an insulating slot liner 3b (hereinafter, referred to as a slot liner) in a slot 3 and inserting a coil 4 which has been previously formed by winding into the inside thereof, It is made with the wedge 3c set. FIG. 22 shows a cross section of the inside of the slot 3.

On the other hand, the stator coil 4 has a shape as shown in FIG. 23, and a winding frame (not shown) having a shape substantially similar to this shape is formed in advance, and the coil 4 is mounted on the winding frame a predetermined number of times. It was made by winding. Then, the stator coil 4 is manually or mechanically used,
It was inserted into the slot from the opening 3d of the slot 3.

[0004]

The prior art described above does not give sufficient consideration to shortening the length of the coil end portion, and has a problem in further downsizing the rotating electric machine.

[0005] The problem that the length of the coil end portion in the prior art is increased will be described below.

The stator coil 4 has a predetermined slot straddling (hereinafter referred to as straddling) determined by the number of poles of the stator, and the length of the coil end is governed by the size of the straddling. In general,
When the number of poles is large, the straddling of the coil is small, so that the length of the coil end is shorter than that having a small number of poles. In addition, it can be formed to some extent short by devising the shape of the coil end portion of the winding frame used when winding the coil. However, if the coil end is significantly shortened, the coil end of the coil to be inserted interferes with the coil end of the inserted coil, and the coil cannot be inserted. Therefore, a method has been used in which the coil end is forcibly molded in the axial direction and the radial direction using external force after the coil insertion is completed, and the coil end is shortened so as not to hinder coil insertion when winding the coil. I was According to this method, since the coil end is formed with a large mechanical force, not only does the slot liner and the coil-coated enamel insulation be damaged, the pressure resistance of the stator does not occur, but also the shortened length is limited even when forcibly formed. Yes, it was far short of the demands of current users.

An object of the present invention is to provide a small-sized rotating electric machine stator in which the length of the coil end portion of the stator coil is reduced in view of the above-mentioned problems of the prior art.

[0008]

In order to achieve the above-mentioned object, according to the present invention, one of four sides constituting a closed circuit of a coil is not formed by winding a coil as in the prior art. The remaining three sides are separated into a U-shape, inserted into a slot, and then connected between the open ends on the opposite side of the U-shape at one side in a radial direction, so that the coil is a closed circuit. The object is to form a coil so as to make one turn. In addition, in order to make the connection sufficiently satisfactory, when connecting the thin U-shaped side open ends and the radial portions, in other words, when the thin bar-shaped pieces are overlapped and connected, the plate thickness of the overlapping portion between them is reduced by half in advance, The plate thickness when both are overlapped is made to be exactly equivalent to the plate thickness of the coil. For this reason, in the U-shaped coil, the surface whose thickness is reduced by half is a surface facing the inner diameter of the stator at one end on the opposite side of the U-shape, for example, the left side, and a surface facing the outer diameter of the stator at the right end. On the other hand, the surface of the thin rod-shaped piece whose thickness is reduced by half is the surface opposite to the coil. With this configuration, when the two are overlapped, the two thin portions of the U-shaped coil act so as to sandwich the thin rod-shaped piece, and a sufficiently strong connection can be realized. When the coil is configured in this way,
Since the straddling width of the coil is determined by the width of the adjacent slot, the axial length of the U-shaped portion protruding from the stator core is equivalent to the width of the adjacent slot. On the other hand, the axial length of the portion protruding from the stator core on the half U-shaped side of the coil occupies only the width of the thin plate connecting piece in the axial direction because it is connected by a thin bar-shaped piece. Can reliably provide a stator having a reduced length.

[0009]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Hereinafter, a stator for a rotating electric machine according to the present invention will be described in detail with reference to the illustrated embodiments.
FIG. 1 is a front view of a stator 1 showing an embodiment of a stator of a rotating electric machine according to the present invention, in which a stator coil 4 is inserted into a slot 3 of a stator core 2.

FIG. 2 is a bird's-eye view showing the assembly of the components constituting the stator 1 according to the present invention.
Shows that a predetermined number of stator coils 4 are inserted into the stator core 2 and the plurality of slots 3 provided in the stator core 2. The stator coil 4 is formed by forming a straight rectangular wire into a U-shape in advance, inserting two straight lines into adjacent slots across the stator teeth 3a, and then forming a thin bar-shaped piece 5
And the end surface 41 and the end surface 42 of the coil 4 opposite to the U-shape.
It is configured such that a one-turn closed circuit is formed by connecting between them.

Furthermore, since this coil is configured to have a predetermined number of turns, when a predetermined number of coils are stacked in a slot and connected by the thin bar-shaped piece 5, one side of the U-shaped coil has a straight end, in other words, When the coil is viewed from the U-shaped side, assuming that the right side is the current inlet, the right side of the U-shaped coil located immediately above the coil in the outer diameter direction and the left side of the coil are connected using the thin bar-shaped piece 5. . Next, in order to configure all coils in a predetermined connection circuit, for example, three phases U, V, and W
The connection ring 6, which has also completed the connection of the crossover wire which is a neutral point as a connection, is connected to the thin plate connection piece 5 to configure the stator so that the stator coil has a desired connection.

Next, a method for forming the stator according to the embodiment of FIG. 2 will be described in detail below. FIG. 3 shows an example of the shape of the stator coil 4. The stator coil 4
Using a rectangular wire, the plate thickness near the both end surfaces is reduced by half like the thin end portion 41 and the thin end portion 42 with different planes. Then, it is formed into a U-shape as shown in FIG. 4 using a jig (not shown).

On the other hand, the thin plate connecting piece 5 is formed by using a flat wire like a coil so as to have a step substantially corresponding to a plate thickness as shown in FIG. Similarly to the stator coil 4, the thickness of the thin plate connecting piece 5 is reduced to half like the thin end portion 51 and the thin end portion 52 by changing the plate thickness near both end surfaces. Also,
As shown in FIG. 6, a plurality of thin plate connecting piece groups 55 are formed in order to form a predetermined number of turns, and input and in-phase coils are connected to a part of the thin plate connecting piece groups 55. Terminal 53 and a thin end portion 54 are provided.

FIG. 7 is a view in which the stator 1 is cut in the axial direction at the slot 3 for explaining a state where the stator coil 4 is inserted into the slot 3. The stator coil 4 is connected to the stator teeth 3 via a slot insulator 7 described later.
is inserted into the adjacent slots 31 and 32 so as to sandwich “a”, and one turn is closed by connecting between the anti-U-shaped end face 41 and the anti-U-shaped end face 42 of the stator coil 4 using the thin plate connecting piece 5. A circuit is configured. Here, in order to form the predetermined number of turns, when connecting with the thin bar-shaped piece 5 as shown in FIG.
When the coil is viewed from one straight end, that is, from the opposite U-shape side, in other words, if the right side end 44 of the coil 4 is the current inlet, the right side of the U-shaped coil 45 located directly above this coil The end 42 and the left side end 41 of the coil 44 are connected using the thin bar-shaped piece 5. Hereinafter, the connection is repeated in the same manner so that a predetermined number of turns is formed.

FIG. 9 is an explanatory diagram for explaining the slot insulator 7. As shown in FIG.
The linear section of the coil can be covered by inserting the linear section of the coil into the storage room 71 and the storage room 72 with a cross-sectional shape that can be stored in close contact with the inner periphery of the slot 3 using an epoxy-based insulating material. It is formed into such a cylindrical shape. In the case of using a flat wire without insulation, when stacking coils in slots, an electric insulator (not shown) is provided between the coils, and after a predetermined number of stacks, the slot insulator 7 is attached to the coil. I do. In this state, it is inserted into the slot of the stator core and connected using the thin plate connecting piece 5 as described above.

Next, FIG. 10 is a diagram for explaining the configuration of the connecting ring 6. As shown in FIG. The connection ring 6 according to the embodiment of the present invention will be described with a three-phase Y connection. First, the U-phase 61, the V-phase 62, and the W-phase 63 are formed in a shape as shown in FIG. 11, the neutral wire 64 is formed as shown in FIG. 12, and assembled as shown in FIG. . Then, the connecting ring 7 is formed by assembling it with a mold (not shown) and integrally molding the same with an epoxy resin 65. The appearance is shown in FIG. This connecting ring 6 is connected to one side of the thin plate connection of the stator coil as shown in FIG. 14 to configure the stator in a desired connection.

Next, the stator core will be described. The stator core has a shape as shown in FIG. 15, and the feature of the embodiment according to the present invention is that the width of the opening 3d of the slot 3 can be formed to a minimum width which is advantageous for the performance of the rotating electric machine without depending on the coil wire diameter. It is. Conventionally, since the coil was guided into the slot from the opening 3d, the opening width was determined from the limitation of manufacturing rather than the performance. However, according to the embodiment of the present invention, it is necessary to insert the coil from the opening 3d. Therefore, there is no restriction on the production, and therefore, the optimum dimensions can be adopted for the performance of the rotating electric machine, and the effect of improving the performance can be obtained.

Since the embodiment according to the present invention is configured as described above, the object can be achieved well. In this case, the coil end 430 of the stator coil 4 has a semicircular shape formed from a diameter corresponding to one slot pitch as shown in FIG. Therefore, the axial length is sufficiently reduced as compared with the conventional technology. The other end of the coil end 431 is
Since both ends 41 and 42 of the stator coil 4 are linearly connected by the thin bar-shaped pieces 5, the axial length is the shortest. Thus, a stator having a short coil end can be provided. According to the present invention, since there is no possibility of damaging the coil and the slot insulator because there is no forcible molding using an external force unlike the prior art, it is possible to provide a stator having good performance without insulation failure.

In order to further improve the electrical insulation strength, an embodiment in which the stator coil 4 is inserted into the slot insulator 7 and molded with an epoxy-based thermosetting resin is very effective. The embodiment in which the thin plate-like piece group 55 is molded in the same manner, makes a predetermined connection with the coil, and molds the whole again when the connection ring 6 is finally connected also works effectively.

Further, as shown in FIG. 16, when the stator iron core teeth 3a are formed so that the portion 33a near the outer diameter is widened and the portion 34a near the inner diameter is narrowed, the tooth width of the teeth is widened on average. As a result, the effect of reducing the magnetic flux density and iron loss is obtained.

FIG. 17 shows an embodiment in which the width of the coil is increased without changing the tooth width. According to this method, since the coil cross-sectional area increases, the current density of the coil decreases, copper loss decreases, and the effect of improving efficiency can be obtained.

FIG. 18 shows a state in which the entire stator 1 is molded with a thermosetting epoxy resin 65 by imaginary lines. As shown in FIG. 19, molding is performed so that a space other than the coil in the slot 3 is filled with the epoxy resin 65. In addition, as shown in FIG.
Is mounted on the frame 8 of the rotating electric machine, the stator coil 4
The molding is performed such that the molding material covering the coil end 430 and the coil end 431 contacts the inner periphery of the frame 8. When formed in this way, Joule heat generated by the current flowing through the coil 4 is transmitted to the molding material filled in the slot, further transmitted to the molding material covering the coil end, and transmitted to the frame. If the rotating electric machine is configured by water cooling, the heat generated is well cooled because the frame has the cooling water passage 88. Since the present invention is configured as described above, the object can be achieved well.

FIG. 24 shows another example of the shape of the fixed coil 4. The illustration of the stator core is omitted.
The stator coil 4 is formed by forming a straight rectangular wire into a U-shape in advance, similarly to the shape described in FIG. When inserting a plurality of coils into the slots of the stator core, when inserting the first coil, the straight portion of the U-shaped coil is inserted into the slot adjacent to the stator teeth from one end side of the stator core. At the time of the next coil insertion, the two sides of the linear portion of the U-shaped coil are inserted from the other end of the stator core into slots adjacent to the stator teeth. Hereinafter, in the same manner, the procedure of inserting the coil is repeated alternately from one end side and the other end side of the stator core, that is, the insertion direction of the coil is alternated. Then, after inserting the plurality of coils, using the thin rod-shaped piece 5, the coil U projecting at both ends of the stator core is removed.
A stator coil having a predetermined number of turns is formed by connecting both ends of the letter side.

At this time, as shown in FIG. 25, the output terminal 41 of the one-turn coil and the input terminal 42 of another one-turn coil are used.
Are connected by a thin bar-shaped piece 5. Further, the output end 44 of the coil and the input end 43 of another one-turn coil are connected by the thin bar-shaped piece 5.

With the above construction, the distance between the upper and lower connecting portions on the right side or the left side of the coil at the connecting portion between the thin bar-shaped piece and the two straight sides on the opposite side of the U-shape is reduced by the thickness of the coil. Corresponding intervals can be ensured. Since this interval is wider than the interval between the upper and lower portions of the connecting portion shown in FIG. 8, an electrical short circuit due to welding beads or the like is less likely to occur. Therefore, it is possible to perform welding with inexpensive welding means without requiring special welding means in consideration of controlling the size of the bead and suppressing thermal deformation.

Further, since coils having two U-shaped and straight coil end shapes are inserted alternately, the coil end shapes on both sides projecting from the stator core end are substantially the same. The difference in the coil end reactance due to the leakage magnetic flux is eliminated, and the performance of the rotating electric machine using the stator is stabilized.

[0027]

According to the present invention, since the length of the coil end portion of the stator coil can be greatly reduced, the resistance and the reactance are small, the amount of copper is reduced, the rotating electric machine is small and lightweight, and has good performance with little insulation deterioration. Can reliably be provided.

[Brief description of the drawings]

FIG. 1 is a front view showing an embodiment of a stator of a rotating electric machine according to the present invention.

FIG. 2 is a bird's-eye view for explaining an embodiment of a stator according to the present invention.

FIG. 3 is an explanatory diagram illustrating an embodiment of a stator coil according to the present invention.

FIG. 4 is an explanatory diagram illustrating an embodiment of a stator coil according to the present invention.

FIG. 5 is an explanatory view for explaining a thin bar piece according to the present invention.

FIG. 6 is an explanatory diagram for explaining a thin bar piece according to the present invention.

FIG. 7 is a partial cross-sectional view illustrating a state where a stator coil according to the present invention is inserted into a slot.

FIG. 8 is an explanatory diagram for explaining connection between a stator coil and a thin plate connecting piece according to the present invention.

FIG. 9 is an explanatory diagram for explaining a slot insulator of a stator coil according to the present invention.

FIG. 10 is an explanatory diagram illustrating an embodiment of a connecting ring according to the present invention.

FIG. 11 is an explanatory diagram illustrating an embodiment of a connecting ring according to the present invention.

FIG. 12 is an explanatory diagram illustrating an embodiment of a connecting ring according to the present invention.

FIG. 13 is an explanatory diagram illustrating an embodiment of a connecting ring according to the present invention.

FIG. 14 is an explanatory diagram for explaining an embodiment of a connection state between a connection ring and a thin bar-shaped piece according to the present invention.

FIG. 15 is an explanatory diagram illustrating an embodiment of a stator core according to the present invention.

FIG. 16 is an explanatory diagram for explaining a stator according to another embodiment.

FIG. 17 is an explanatory diagram for explaining a stator according to another embodiment.

FIG. 18 is an explanatory diagram illustrating a molded stator.

FIG. 19 is an explanatory diagram for explaining the vicinity of a molded slot.

FIG. 20 is an explanatory view showing that a molded stator is mounted on a frame.

FIG. 21 is an explanatory diagram for explaining a conventional stator.

FIG. 22 is an explanatory diagram for explaining a conventional stator.

FIG. 23 is an explanatory diagram for explaining a stator coil according to the related art.

FIG. 24 is an explanatory diagram for explaining another embodiment of the stator coil according to the present invention.

FIG. 25 is an explanatory diagram for explaining another embodiment of the stator coil according to the present invention.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 ... Stator 2 ... Stator iron core 3, 31, 32 ... Slot 3a ... Stator iron core tooth part 3b ... Slot liner 3c ... Wedge 3d ... Opening 4 ... Stator coil 5 ... Thin plate bar 6 ... Connection ring 7 ... Slot Insulator 8 Frame 41, 42 Stator coil end face 51, 52 Thin bar-shaped one end face 53, 54 Terminal 55 Thin bar-shaped piece group 61, 62, 63, 64 U-phase, V-phase, W-phase, medium Property line 65: Mold material 71, 72 ... Storage room 88 ... Water channel 430, 431 ... Coil end

Continued on the front page (51) Int.Cl. ⁷ Identification symbol FI Theme coat II (Reference) H02K 3/34 H02K 3/34 C Z 3/44 3/44 B 15/085 15/085 15/12 15/12 E (72) Inventor Suetaro Shibukawa 2477 Takaba, Hitachinaka City, Ibaraki Prefecture Inside Hitachi Car Engineering Co., Ltd. (72) Inventor Osamu Koizumi 2520 Oji Takaba, Hitachinaka City, Ibaraki Prefecture Inside Hitachi Automotive Equipment Group (72) Inventor Toshiaki Ueda 2520 Takahiro, Hitachinaka-shi, Ibaraki Pref.Hitachi, Ltd.Automotive equipment group (72) Inventor Yasuhiko Kimura 2520 Ojitakaba, Hitachinaka-shi, Ibaraki Pref.Hitachi, Ltd.Automotive equipment group (72) Inventor Takehiro Owada 2520 Oita Takaba, Hitachinaka-shi, Ibaraki Pref.Hitachi, Ltd.Automotive Equipment Group (72) Inventor Yoshimi Mori 2520 Ojitakaba, Hitachinaka-City, Ibaraki Pref.Hitachi Automotive Equipment Group (72 ) Akiba Sanshiro Ohara 2520 Takaba, Hitachinaka-shi, Ibaraki Pref.Hitachi, Ltd.Automotive Equipment Group (72) Inventor Hisashi Kondo 4-6, Kanda Surugadai, Chiyoda-ku, Tokyo Hitachi, Ltd. (72) Inventor Anan Hiroyasu 4-6-6 Kanda Surugadai, Chiyoda-ku, Tokyo Inside Hitachi, Ltd. (72) Inventor Shuichi Hara 46-1, Tomioka, Oji, Nakajo-cho, Kitakanbara-gun, Niigata Japan Industrial Equipment Group, Hitachi, Ltd. (72) Hidemitsu Kobayashi Ibaraki, Ibaraki 2520 Oita Takaba, Hitachinaka-shi, Prefecture F-term in the Automotive Equipment Group of Hitachi, Ltd. (Reference) BB10 BB14 CC01 CC05 CC15 DA15 PB02 PB03 QB03 5H615 AA01 BB07 BB14 PP01 PP10 PP13 PP14 PP15 QQ03 QQ12 QQ27 RR01 SS10 TT03 TT34

Claims (6)

[Claims] 1. A stator for a rotary electric machine in which a stator coil is mounted in a plurality of slots of a stator core, wherein a straight rectangular wire is previously formed into a U-shape.
Two straight sides are inserted into slots adjacent to each other across the stator teeth, and then the two ends of the coil are connected to each other on the opposite U-shaped side by a thin bar-shaped piece. Then, a plurality of the coils are inserted, and the stator coil is formed with a predetermined number of turns by connecting the opposite ends of the U-shaped side as described above. When overlapping and connecting, the plate thickness of the portion where both are overlapped is halved, and when both are overlapped, the surface for reducing the plate thickness by half so as to be equivalent to the plate thickness of the rectangular coil is a coil. On the left side of one end, a coil is formed in advance so that the thickness of the surface facing the inner diameter of the stator is halved, and on the right side, the thickness of the surface facing the outer diameter of the stator is halved. , Halving the thickness of the surface opposite to the coil, When's the superposed stator of a rotary electric machine, characterized by being configured to connect so as to sandwich the thin rod-shaped piece with a straight line portion two sides of the U-shaped coil. 2. The stator for a rotating electric machine according to claim 1, wherein a plurality of rectangular wires, which are not insulated, are stacked with an electrical insulator interposed between the rectangular wires in the radial direction of the stator core.
A coil housing material formed of an epoxy-based insulating material and formed into a cylindrical shape having a cross-sectional shape capable of being housed in close contact with the inner periphery of the slot is inserted into the linear portion of the coil from the non-U-shaped side of the laminated stator coil And then in this state,
Molding with an epoxy-based thermosetting resin, molding is performed in the same manner in a state where a predetermined number of thin plate-like pieces are stacked, and a predetermined number of turns is formed by overlapping and connecting the coil and the thin plate-like piece. And the stator of the rotating electric machine. 3. The stator for a rotating electric machine according to claim 1, wherein the stator core, the coil, and the connection ring have predetermined structures.
The entire stator is molded with a thermosetting epoxy resin.Especially when the stator is mounted on the rotating electric machine frame so that the space in the slot other than the coil is filled with the epoxy resin, the coil end of the stator coil is A stator for a rotating electric machine, wherein a covering mold material is formed so as to contact an inner periphery of the frame. 4. The stator for a rotating electric machine according to claim 1, wherein the stator core is formed by using a stator core formed such that a portion near the outer diameter is widened and a portion near the inner diameter is narrowed. A stator for a rotating electric machine, characterized in that: 5. The stator for a rotating electric machine according to claim 1, wherein the width of the coil inserted into the slot increases from the inner diameter side of the stator toward the outer diameter side of the stator. Characteristic stator of rotating electric machine. 6. A stator for a rotating electric machine according to claim 1, wherein when a plurality of coils, each of which is formed by forming a straight rectangular wire into a U-shape in advance, are inserted into the slot, Insert the two sides of the linear portion of the U-shaped coil into slots adjacent to the stator teeth from one end of the stator core, and fix from the other end of the stator core at the next coil insertion Insert the coils alternately from one end and the other end of the stator core so that the two sides of the straight portion of the U-shaped coil are inserted into the slots adjacent to each other with the child teeth therebetween. A stator for a rotating electric machine, wherein a stator coil having a predetermined number of turns is formed by connecting both ends on the opposite U-shaped side of the coil using a thin bar-shaped piece after inserting the coil.