JP2010004723A - Molding apparatus and molding method - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a molding apparatus and a molding method that can appropriately assure the distance between a coil and a core. <P>SOLUTION: When movable plates 72 move toward the opening direction and one movable plate 72 is brought into contact with a coil-side part, a coil member 20 is forced to move to one side. When both of the movable plates 72 come into contact with the coil-side part of the coil member 20, the position of the coil member 20 is fixed. A molding member 31 is formed by injecting a resin around a core cylinder part 63 and the coil member 20, in this state. Thereafter, a cassette coil consisting of the coil member 20 and the molding member 31 is attached to a core. At this time, the distance between the core and the coil member 20 comes within a predetermined range that can prevent partial discharge. Thus, partial discharge can be prevented. <P>COPYRIGHT: (C)2010,JPO&INPIT

Description

  The present invention relates to a molding apparatus and a molding method for forming a cassette coil disposed in a motor, a generator, or the like.

  A stator (stator) of a motor or a generator is configured by winding a coil around a core. In the case of a stator having a yoke part and a tooth part protruding from the yoke part, the coil is wound around the tooth part. Recently, a structure of a cassette coil formed by resin molding of a coil member has been proposed. In that case, a stator coil is assembled by setting a cassette coil formed in advance in the tooth portion. Patent Document 1 discloses a stator structure using a cassette coil.

The core of Patent Document 1 has an annular stator teeth body and an annular stator yoke. The ring-shaped stator teeth body is formed by connecting a plurality of teeth in a ring shape. The ring-shaped stator yoke is formed by connecting a plurality of yokes in a ring shape. The cassette coil is attached to each tooth in the annular stator teeth body.
JP 2007-195333 A

  The stator of Patent Document 1 makes it easy to assemble the stator and eliminates the need for an insulating insulator or the like. Therefore, it is expected that productivity is improved and manufacturing costs are reduced.

  However, the structure of Patent Document 1 has the following problems. When the cassette coil is attached to the core (the teeth of the ring-shaped stator teeth body in the same document), a gap is generated between the core and the opening of the cassette coil. For this reason, the position of the cassette coil may fluctuate during use, and the distance between the coil and the core may be partially reduced. At this time, if the distance between the coil and the core is too small, partial discharge may occur and the insulating film may deteriorate.

  The objective of this invention is providing the molding apparatus and the molding method which can ensure the distance of a coil and a core appropriately.

The molding apparatus of the present invention resin-molds a coil member wound in a shape surrounding a core. The mold member of the molding apparatus has a core part and a die cavity that are provided so as to correspond to the shape of the core in anticipation of heat shrinkage. Further, position setting means for setting the distance from the core portion of the coil member within a predetermined range is provided.
The lower limit of the predetermined range in the present invention may be an insulation distance determined by the structure of the stator. In addition, the upper limit of the predetermined range in the present invention does not necessarily have a critical significance, and therefore there is no need to have an upper limit.

  When resin molding is performed using this molding apparatus, a mold body (cassette coil) is formed. And in the stator formed by mounting the mold body on the core, the distance between the coil and the core is kept within a predetermined range. Therefore, an insulation distance for preventing discharge can be secured between the core and the coil member.

  Preferably, the distance from the core part of the pair of coil side parts of the coil member is made substantially equal by the position setting means. Thereby, the insulation distance for preventing discharge can be secured while keeping the size of the mold body small.

  More preferably, the distance from the core portion of the pair of coil end portions of the coil member is also substantially equal.

  As the position setting means, for example, there is one having a pair of plate members for moving a coil member and a moving mechanism. The moving mechanism moves a pair of plate members in the opposite directions by the same distance. Thereby, the distance from the core part of a pair of coil end parts or coil side parts can be made equal.

  If the distance between the core and the coil member is smaller than 0.1 mm, partial discharge as described above tends to occur. On the other hand, if the distance between the core and the coil member exceeds 1.0 mm, the dimension becomes excessive. Further, since the proportion of the conductor area entering the slot is reduced, the output of a motor or the like in which the stator is arranged is reduced. Therefore, the predetermined range is preferably 0.1 mm to 1.0 mm.

  The molding method of the present invention is performed by the following procedure using the molding apparatus. First, the distance from the core part of the coil member is set within a predetermined range by the position setting means. Thereafter, a resin is injected around the core portion and the coil member to form a mold body.

  By this method, the resin is filled between the core portion corresponding to the core and the coil member. Therefore, the partial discharge function is improved by the resin having a dielectric constant larger than that of air. Further, the function of radiating the heat of the core and the coil member is increased by the resin having higher thermal conductivity than air.

  According to the molding apparatus and the molding method of the present invention, it is possible to appropriately ensure the distance between the coil and the core in the molded body. Therefore, occurrence of partial discharge can be suppressed.

-Coil assembly process-
FIG. 1 is a perspective view showing a method for assembling a coil member according to an embodiment of the present invention.
The assembling apparatus according to the present embodiment includes a coil winding roller 14 provided with four individual winding portions 14a to 14d, a collect roller 15, a pinch roller 16, a plate thickness correcting roller 17, and a bending roller 18. I have. The individual winding portions 14a to 14d of the coil winding roller 14 are configured to rotate independently of each other.

  The four coil wires 11 unwound from the individual unwinding portions 14a to 14d are gradually collected in the collecting region Ra. The four coil wires 11 are bundled into a single rectangular wire by the collecting roller 15. As shown in an enlarged detail in the lower left diagram of FIG. 1, the divided rectangular wire 10 is configured by collecting four coil wires 11 in a flat plate shape. Since the coil wires 11 are electrically connected to each other at both ends, the divided rectangular wire 10 substantially functions as one rectangular wire. Each coil wire 11 includes a copper wire 12 having a substantially rectangular cross section and a coating film 13 that covers the copper wire 12. The skin covering film 13 is made of an imide resin typified by polyimide, polyamideimide, polyesterimide or the like.

  The axial direction of the pinch roller 16 and the axial direction of the plate thickness correcting roller 17 are substantially orthogonal to each other. The divided rectangular wire 10 is bent substantially at a right angle by the bending roller 18 in the bending region Rb. Although not shown, a guide member is provided between the pinch roller 16, the bending roller 18, and the plate thickness correcting roller 17. The guide member sandwiches the divided rectangular wire 10 along the flat plate surface and both end surfaces. The divided rectangular wire 10 is bent into an edgewise shape in a direction in which the flat plate surface is substantially orthogonal to the roller surface of the bending roller 18.

The bent divided rectangular wires 10 are overlapped with each other in the winding region Rd. Thereby, the coil member 20 wound so that the circumference | surroundings of the core (tooth part) mentioned later may be enclosed is formed. When the divided rectangular wire 10 is viewed as a single rectangular wire, a so-called edgewise coil shape is formed. Although not shown, the assembling apparatus is equipped with a mechanism for rotating the coil member 20.
However, the coil shape of the present invention is not limited to the flat dividing line of the present embodiment. The present invention can also be applied to a coil member in which one coil wire is wound. Further, the present invention can be applied to a coil having an arbitrary cross-sectional shape such as a circular, rectangular, or polygonal cross-sectional shape.

-Resin molding process-
FIG. 2 is a side view of a molding apparatus 70 used in the resin molding process of the present embodiment. The molding apparatus 70 includes a base member 75 on which the lower mold 60A is installed. A ball screw 76 extending in the vertical direction is attached to the base member 75. A vertically moving member 77 containing a ball nut that engages with the ball screw 76 is provided. A coil position setting unit 71 (position setting means) that can be rotated around the shaft member 78 is connected to the vertically moving member 77. As shown in the enlarged cross-sectional view of the same figure, the coil position setting unit 71 includes a right screw 74A and a left screw 74B that rotate simultaneously.

A pair of moving plates 72 (plate members) that engage with the right screw 74A and the left screw 74B are attached. The pair of moving plates 72 are flat plates extending in the vertical direction in parallel with each other. When the right screw 74A and the left screw 74B rotate, the pair of moving plates 71 move by the same distance in the opening direction or the closing direction. As will be described below, the moving plate 71 moves the position of the coil member 20 to a symmetrical position.
However, the mechanism for moving the moving plate 72 is not limited to the structure of this embodiment.

  FIG. 3 is a perspective view showing a state where the coil position setting unit 71 is lowered and the moving plate 72 is inserted into the lower mold 60A. The coil member 20 is installed in the die cavity Dc of the lower mold 60A. Each of the pair of moving plates 72 is located inside the coil member 20.

  In the following description, the coil side portion of the coil member 20 is a portion parallel to the xz plane shown in FIG. The coil end portion of the coil member 20 is a portion parallel to the xy plane shown in FIG. However, in the case of a rotary motor, the x direction is the rotor side direction, the y direction is the circumferential direction, and the z direction is the motor shaft direction.

  5A to 5C are cross-sectional views showing the procedure of the resin molding process. 5A to 5C show structures in a cross section parallel to the yz plane shown in FIG. 5A and 5B show a procedure for adjusting the position of the coil side portion of the coil member 20. When adjusting the position of the coil end portion, the coil position setting portion 71 is rotated by 90 ° around the shaft member 78 from the position shown in FIG.

  The central axis OO of the lower mold 60A shown in FIG. 5A includes the center of the shaft member 78. Therefore, the distance from the central axis OO of the pair of moving plates 72 is the same value y1. On the other hand, the coil member 20 is initially installed at an arbitrary position in the die cavity Dc (concave portion) of the lower mold 60A. Therefore, the distance between the outer surface of each coil side part and the inner surface of the lower mold 60A is different from each other.

  From this state, a motor (not shown) operates to rotate the screws 74A and 74B, and the moving plate 72 moves in the opening direction. When one moving plate 72 comes into contact with the inner side surface of the coil side portion, the coil member 20 is moved to one side. Thereafter, when both moving plates 72 come into contact with the inner side surfaces of the coil side portions of the coil member 20, the motor stops. At this time, the position of the coil member 20 in the y direction is determined.

  FIG. 5B shows a state when the position of the coil member 20 is determined. At this time, the distance between each moving plate 72 and the center line OO of the lower mold 60A is the same value y2. Each moving plate 72 and both coil side portions are in contact with each other. Therefore, the distance between the outer surface of each coil side portion and the inner surface of the lower mold 60A is equal to each other.

Thereafter, the moving plate 72 is rotated by 90 °, and the position of the coil end portion of the coil member 20 is set in the same procedure. As a result, the coil member 20 is set at the center position of the lower mold 60A.
Note that another pair of moving plates parallel to the y direction shown in FIG. 5 may be provided. In that case, the position of a coil side part and a coil end part can be set simultaneously with a total of four moving plates.

  FIG. 4 is a perspective view showing a state in the middle of setting the upper mold 60B to the lower mold 60A. When the positioning of the coil member 20 is completed, the coil position setting unit 71 shown in FIG. 2 is retracted upward. Then, the upper mold 60B is set in the lower mold 60A. The lower mold 60A and the upper mold 60B are engaged with each other so that their center positions coincide with each other.

The upper mold 60B is provided with a core portion 63 having a shape and a dimension corresponding to the tooth portion of the core. The core portion 63 is set in advance so as to be positioned at the center position of the die cavity Dc of the lower mold 60A. The core portion 63 of the upper mold 60B is inserted into the die cavity Dc of the lower mold 60A.
At this time, the distance between the coil member 20 set at the center position of the lower mold 60A and the core portion 63 is as follows. That is, the distance (gap) between each coil side portion of the coil member 20 and the side surface of the core portion 63 is equal to each other. Further, the distance (gap) between each coil end portion of the coil member 20 and the side surface of the core portion 63 is also equal to each other.

  FIG. 5C shows a state where the upper mold 60B is engaged with the lower mold 60A and the mold member 31 (resin) is injected. In this step, resin is injected around the core portion 63 and the coil member 20 to form the mold member 31.

FIG. 6 is a perspective view showing the structure of the cassette coil 30 (molded body) and the split core 51 formed in the molding process. In FIG. 6, the mold member 31 is displayed as a transparent body.
Of the coil member 20, two terminals 21 and 22 projecting toward the coil end side are exposed from the mold member 31. The mold member 31 includes an opening 33 and two flanges 35 extending in the direction opposite to the x direction. When the cassette coil 30 is mounted, the tooth portion 51 b is fitted into the opening 33 of the mold member 31. Further, the upper and lower surfaces of the yoke portion 51 a are sandwiched between the two flange portions 35 of the cassette coil 30.

  As the mold member 31, PPS resin (polyphenylene sulfide), LCP resin (liquid crystal polymer), epoxy resin, unsaturated polyester resin (BMC), or the like is used.

-Split stator and stator structure-
The split core 51 has a yoke part 51 a and a teeth part 51 b that protrudes from the yoke part 51 to the rotor side. In the present embodiment, the split core 51 has a laminated steel plate structure in which a large number of magnetic steel plates are laminated with an insulating layer interposed therebetween. However, you may employ | adopt what is called a powder core structure formed by compression-molding the magnetic powder which has an insulating film.

  7A and 7B are a longitudinal sectional view and a transverse sectional view showing the structure of the split stator 50A. FIG. 7A shows a structure in a cross section parallel to the xy plane shown in FIG. FIG. 7B shows a structure in a cross section parallel to the yz plane shown in FIG.

In the present embodiment, the opening 33 of the cassette coil 30 substantially matches the outer shape of the tooth portion 51 b of the split core 51. Therefore, the split stator 50A is assembled by fitting the cassette coil 30 to the tooth portion 51b.
Therefore, the distance between the teeth 51b and the coil member 20 is in a predetermined range of 0.1 mm to 1.0 mm.

FIG. 8 is a cross-sectional view showing a schematic structure of the stator 50 in which the divided stator 50A is annularly combined. A rotor (not shown) provided with permanent magnets is disposed inside the stator 50.
Instead of the split core 50, an annular integrated stator that is continuously connected by a yoke portion may be used. In that case, a plurality of teeth portions protrude from the stator to the rotor side.

The following procedure is suitable for assembling the stator 50. First, the cassette coil 30 is mounted on the tooth portion 51b, and the divided stator 50A is assembled. Next, each divided stator 50A formed in this way is assembled in an annular shape. Thereafter, the stator 50 is assembled by being enclosed from the outside by using a ring member or the like (not shown).
First, after assembling the split core 50A in an annular shape, each cassette coil 30 may be attached to the tooth portion 51b. Further, after assembling the cassette coils 30 into an annular shape, the teeth 51b may be inserted into each cassette coil 30.

  According to the present embodiment, the distance between the coil member 20 and the tooth portion 51b is set within a predetermined range. Therefore, while using the split stator 50A, it is possible to prevent partial discharge due to the partial approach of both.

The structure of the molding apparatus 70 is not limited to the present embodiment. However, this embodiment has advantages in the following points.
Depending on the structure of the coil, when the coil member 20 is wound, an error from the designed shape becomes large. In particular, when the flat dividing line 10 is wound edgewise as in this embodiment, a large plastic deformation force is involved. Therefore, a spring back may occur in a part of the coil member 20. In addition, a part of the coil member 20 may not be sufficiently plastically deformed.

  In that case, according to the present embodiment, one moving plate 72 is in contact with the most inwardly protruding portion of the coil member 20. Thereafter, both moving plates 72 are moved by the same distance to position the coil member 20. Therefore, even when the shape of the coil member 20 is locally deviated from the design dimension, the insulation distance can be ensured.

  In addition, the distance between the tooth portion 51b and the pair of coil side portions is made equal by using the moving plate 72 of the present embodiment. Therefore, a necessary insulation distance can be ensured while keeping the dimension of the split stator 50A small.

In the present embodiment, the predetermined range is 0.1 mm to 1.0 mm, but is not limited to this. Generally, when the distance between the core and the coil member is smaller than 0.1 mm, partial discharge tends to occur.
However, the insulation distance for preventing partial discharge differs depending on the voltage between the coil and the core and the dielectric constant of the member disposed between them. Therefore, the lower limit of the predetermined range in the present invention may be an insulation distance determined by the structure of the stator. In addition, the upper limit of the predetermined range in the present invention does not necessarily have a critical significance, and therefore there is no need to have an upper limit.
However, generally, when the distance between the core and the coil exceeds 1.0 mm, the dimension becomes excessive. Further, since the proportion of the conductor area entering the slot is reduced, the output of a motor or the like in which the stator is arranged is reduced. Therefore, the upper limit of the predetermined range is preferably 1.0 mm.

  In the present embodiment, the gap between the coil member 20 and the tooth portion 51 b is filled with the mold member 31. Since the resin in the mold member 31 has a larger dielectric constant than air, this structure also improves the discharge suppression function. Since the mold member 31 has a larger thermal conductivity than the gap, the heat of the tooth portion 51b and the coil member 20 is easily released to the outside.

  However, a gap may exist between the coil member 20 and the tooth portion 51b. If the core part 63 shown in FIG. 4 and FIG. 5 is made larger than the teeth part 51b, it will become a structure where a clearance gap exists between both. Even in this case, if the distance between the core part 63 and the coil member 20 is 0.1 mm or more, partial discharge can be prevented. This is because even if the relative position between the coil member 20 and the tooth portion 51b varies, the insulation distance between the two is ensured.

(Other embodiments)
The mold member 31 may be provided only on the coil side portion of the tooth portion 51b. The coil side portion is a portion of the tooth portion 51b or the coil member 20 that is parallel to the xz plane shown in FIG. If heat can be radiated from the coil side portion where the amount of heat generation is large, overheating of the tooth portion 51b and the coil member 20 can be effectively prevented.
However, it is more preferable that the mold member 31 is also provided in the coil end portion of the tooth portion 51b.

  In the said embodiment, the salient pole structure in which the teeth part 51b protruded from the yoke part 51a was employ | adopted as a structure of a core. However, the core structure of the present invention is not limited to such an embodiment, and other structures can be adopted.

  The teeth 51b may have a straight shape or a tapered shape that narrows toward the tip. When the shape of the teeth portion 51 is tapered, it is preferable that the moving plate 72 also expands downward. That is, it is preferable that the moving plate 72 extends along the shape of the tooth portion 51b.

  In the above embodiment, the example in which the cassette coil is used as a part of the rotary motor has been described. However, the cassette coil of the present invention can also be used for linear motors, generators, reactors, transformers, and the like.

  The structure of the embodiment of the present invention disclosed above is merely an example. Therefore, the scope of the present invention is not limited to the scope of these descriptions. The scope of the present invention includes the scope indicated by the recitation of the claims. Furthermore, the scope of the present invention includes all modifications within the meaning and range equivalent to the description of the claims.

  The cassette coil and the stator of the present invention can be used for a linear motor, a generator, a reactor, a transformer, and the like. These devices are arranged in hybrid vehicles, electric vehicles, fuel cell vehicles, robots, and various industrial equipment.

It is a perspective view which shows the assembly method of the coil member which concerns on embodiment of invention. It is a side view of the mold apparatus used at the resin mold process of embodiment. It is a perspective view which shows the state by which the coil position setting part descend | falls and the moving plate was inserted in the lower metal mold | die. It is a perspective view which shows the state in the middle of setting the upper metal mold | die to a lower metal mold | die. (A)-(c) is a cross-sectional view which shows the procedure of a resin mold process. It is a perspective view which shows the structure of the cassette coil and division | segmentation core which were formed at the resin mold process. (A), (b) is the longitudinal cross-sectional view and cross-sectional view which show the structure of a division | segmentation stator. It is sectional drawing which shows the schematic structure of the stator which combined the division | segmentation stator in cyclic | annular form.

Explanation of symbols

Dc Die cavity (concave)
10 Divided rectangular wire 20 Coil member 21, 22 Terminal 30 Cassette coil (molded body)
31 Mold Member 33 Opening 35 Gutter 50 Stator 50A Divided Stator 51 Divided Core 51a Yoke 51b Teeth 60A Lower Die 60B Upper Die 63 Core Part 70 Molding Device 71 Coil Position Setting Unit (Position Setting Means)
72 Moving plate (plate member)
74A Right screw 74B Left screw 75 Base member 76 Ball screw 77 Vertical movement member 78 Shaft member

Claims (6)

A molding apparatus for resin-molding a coil member wound in a shape surrounding a periphery of a core,
A core member corresponding to the core, and a mold member having a recess in which the coil member is installed;
Position setting means for setting a distance from the core portion of the coil member within a predetermined range;
A molding apparatus. The molding apparatus according to claim 1,
The position setting means is a molding apparatus in which the distance between the pair of coil side portions of the coil member from the core portion is substantially equal. The molding apparatus according to claim 1 or 2,
The position setting means is a molding apparatus in which the distance between the pair of coil end portions of the coil member from the core portion is also substantially equal. The molding apparatus according to claim 2 or 3,
The position setting means includes
A pair of plate members for moving the coil members;
A moving mechanism for moving the pair of plate members in opposite directions by the same distance;
A mold apparatus. In the molding apparatus according to any one of claims 1 to 4,
The mold apparatus whose said predetermined range is 0.1 mm-1.0 mm. A coil member molding method using the molding apparatus according to any one of claims 1 to 5,
Using the position setting means, the step of setting a distance from the core portion of the coil member within a predetermined range (a);
Closing the mold and injecting resin around the core and the coil member to form a mold body (b);
A mold method comprising:

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