JP6891799B2 - Molding equipment for coils - Google Patents

Description

The present invention relates to a coil forming apparatus that bends and forms a flat conductor by sandwiching the flat conductor in the width direction using a convex shape and a concave shape having a molding surface asymmetrical with respect to the center in a plan view including a flat conductor extending linearly. ..

Conventionally, as this type of coil forming apparatus, a first forming die (movable die) provided with a crank forming surface and a second forming die (fixed type) provided with a support surface for supporting a flat conductor having a predetermined length. A mold) and a flat conductor arranged in the second molding mold are pressed against the crank forming surface of the second molding mold and a force is continuously applied to form a crank portion on the flat conductor. (See, for example, Patent Document 1).

Japanese Unexamined Patent Publication No. 2014-135857

Here, the flat conductor is bent in the width direction by using a first molding die (concave mold) and a second molding die (convex mold), which have molding surfaces having an asymmetric shape with respect to the center in a plan view including the flat conductor. When molding, it is desirable to position the flat conductor by sandwiching it from both ends in the longitudinal direction with a positioning member so that the flat conductor does not shift in position. The positioning member includes a first positioning member including a first contact member that contacts one end of the flat conductor, and the other end of the flat conductor that is arranged so that the first contact member and the contact surfaces of the first contact member face each other. It is conceivable that a second positioning member including a second contact member that comes into contact with the conductor and an urging member that urges the second contact member toward the first contact member side can be considered. However, when the flat conductor is sandwiched in the width direction between the convex and concave shapes that are asymmetrical with respect to the center and bent, the flat conductor contacts at two points, the top of the convex shape and the edge on one side of the concave shape. Then, a phenomenon occurs in which the flat conductor rotates around the convex top. When the flat conductor rotates, one end thereof is disengaged from the contact by the first positioning member (first contact member), and the flat conductor is displaced in the longitudinal direction due to the urging force from the urging member of the second positioning member. In some cases, the flat conductor is bent and molded by the convex and concave molds in a misaligned state, and as a result, the molding accuracy is deteriorated.

The main object of the coil molding apparatus of the present invention is to suppress the positional deviation of the flat conductor in the longitudinal direction to further improve the molding accuracy during bending molding.

The coil forming apparatus of the present invention has adopted the following means in order to achieve the above-mentioned main object.

The coil forming apparatus of the present invention is
A coil molding apparatus for bending and molding the flat conductor by sandwiching the flat conductor in the width direction using convex and concave molds having molding surfaces asymmetrical with respect to the center in a plan view including a flat conductor extending linearly.
A first positioning member including a first contact member that contacts one end of the flat conductor, and
A second contact member which is arranged so that the first contact member and the contact surfaces of each other face each other and abuts on the other end of the flat conductor, and the second contact member on the side of the first contact member. A second positioning member that includes a urging member that urges the conductor toward the surface, and positions the flat conductor together with the first positioning member by sandwiching the flat conductor in the longitudinal direction.
With
Each contact surface of the first and second contact members is formed by an arcuate concave curved surface.
The radius of curvature of the concave curved surface is set to a length corresponding to the distance from the contact portion to the end portion of the flat conductor that comes into contact with the top of the convex shape during the bending molding.
The gist is that.

In the case of bending and molding a flat conductor by sandwiching it in the width direction using a convex and a concave shape having a molding surface asymmetrical with respect to the center in a plan view including a flat conductor extending in a straight line, the top and the concave of the convex shape are formed. A phenomenon occurs in which the flat conductor is in contact with the flat conductor at two points with the edge on one side, and the flat conductor rotates around the convex top. In the coil molding apparatus of the present invention, as positioning members for positioning a flat conductor in the longitudinal direction, a first positioning member including a first contact member that contacts one end of the flat conductor, and the first contact member and each other A second contact member that is arranged so that the contact surfaces face each other and abuts on the other end of the flat conductor, and a urging member that urges the second contact member toward the first contact member side. 2 Positioning member and. Further, each contact surface of the first and second contact members is formed by an arcuate concave curved surface, and the radius of curvature of the concave curved surface is brought into contact with the top of the convex shape during bending molding on a flat conductor. Determine the length corresponding to the distance from the part to the end. As a result, even if the flat conductor rotates about the top of the convex shape during bending, both ends of the flat conductor are kept in contact with the contact surfaces of the first and second contact members. be able to. As a result, the positional deviation of the flat conductor in the longitudinal direction can be suppressed, and the molding accuracy at the time of bending molding can be further improved.

It is a front view of the stator 10 for a motor. It is a front view of the segment coil 13 which constitutes a stator coil 14. It is a block diagram which shows the outline of the structure of the coil forming apparatus 20 as one Example of this invention. It is explanatory drawing which shows the state of bending the flat conductor D. It is explanatory drawing which shows the state of bending the flat conductor D. It is explanatory drawing which shows the state of bending the flat conductor D.

Next, a mode for carrying out the present invention will be described with reference to examples.

FIG. 1 is a front view of the stator 10 for an electric motor, and FIG. 2 is a front view of a segment coil 13 constituting the stator coil 14. The stator 10 for an electric motor is combined with a rotor to form a three-phase AC generator motor, and is used as a traveling electric motor or generator for, for example, an electric vehicle or a hybrid vehicle. The stator 10 is composed of a plurality of (three-phase) stator cores 12 having a plurality of slots formed at equal intervals in the circumferential direction on the inner peripheral side and a plurality of segment coils 13 inserted into the slots of the stator core 12, respectively. It includes a stator coil 14. The stator core 12 is formed by laminating a plurality of stator plates formed by punching out non-oriented electrical steel sheets, and a plurality of teeth protruding inward in the radial direction so as to form a plurality of slots on the inner peripheral side. Has.

The segment coil 13 is formed by bending a flat conductor D extending linearly as a material of the segment coil 13 into a substantially U shape. The flat conductor D is a wire rod having a rectangular cross section formed of a highly conductive metal such as copper, and its surface is coated with an insulating film such as enamel resin in order to secure insulation with the stator core 12. It is covered. As shown in FIG. 2, the segment coil 13 is formed by edgewise bending at two straight portions 13a inserted into the slots of the stator core 12 and an end portion of the straight portion 13a opposite to the free end side. It has one shoulder portion 13b and a crank portion 13c formed by flatwise bending at substantially the center of both shoulder portions 13b. The free-end end of the straight portion 13a of the segment coil 13 is welded to the free-end end of the straight portion 13a of another adjacent segment coil 13 to form the stator coil 14.

The crank portion 13c of the segment coil 13 is formed by using the coil forming apparatus 20. FIG. 3 is a configuration diagram showing an outline of the configuration of the coil forming apparatus 20 as an embodiment of the present invention. As shown in the figure, the coil forming apparatus 20 includes a convex mold 22 as a fixed mold and a concave mold 24 as a movable mold that bends and forms a flat conductor D together with the convex mold 22 in the width direction. The convex type 22 and the concave type 24 each have crank portion forming surfaces 22a and 24a formed asymmetrically with respect to the center (left-right asymmetry in the drawing) in a plan view including the flat conductor D, and the crank portion forming surfaces 22a. By pressurizing the flat conductor D in the width direction (flatwise direction) at 24a, the flat conductor D is bent into a crank shape to form the crank portion 13c.

Further, the coil forming device 20 includes a positioning device 30 that positions the flat conductor D by sandwiching the flat conductor D from both ends thereof in the longitudinal direction when the flat conductor D is bent and molded by the convex type 22 and the concave type 24. The positioning device 30 includes a first positioning member 32 that abuts and holds one end of the flat conductor D, and a second positioning member 34 that abuts and holds the other end of the flat conductor D. The first positioning member 32 is formed by an arcuate concave curved surface, and has a first contact member (fixing member) 33 including a contact surface 33a to which one end of a flat conductor D is contacted. The second positioning member 34 is formed by an arcuate concave curved surface and is arranged so as to face the contact surface 33a, and includes a second contact surface 35a to which the other end of the flat conductor D is in contact. It has a (movable member) 35 and an urging member (for example, a coil spring) 36 that urges the second contact member 35 toward the first contact member 33 side. The first and second positioning members 32 and 34 use the urging force of the urging member 36 to abut the flat conductor D against the first contact member 33 as a fixing member, whereby the first and second contact members Positioning is performed by sandwiching the flat conductor D in the longitudinal direction with 33 and 35.

Next, the operation of the coil forming apparatus 20 of the embodiment configured in this way will be described. 4 to 6 are explanatory views showing a state in which the flat conductor D is bent and molded. The flat conductor D is carried in between the convex 22 and the concave 24 by a carry-in device (not shown) so that the arrangement direction of the convex 22 and the concave 24 is the width direction, and when bending molding is completed, the flat conductor D is carried in by a carry-out device (not shown). It is carried out. When the flat conductor D is carried into the coil forming apparatus 20, the coil forming apparatus 20 first brings the contact surface 33a of the first contact member 33 into contact with one end of the flat conductor D and the flat conductor as shown in FIG. The contact surface 35a of the second contact member 35 is brought into contact with the other end of D, and the second contact member 35 is urged toward the first contact member 33 by the urging member 36. The flat conductor D is positioned by sandwiching it in the longitudinal direction from both ends thereof.

Next, the concave type (movable type) 24 is moved toward the convex type (fixed type) 22. As described above, the convex 22 and the concave 24 are formed so that the crank portion forming surfaces 22a and 24a are asymmetric with respect to the center in a plan view including the flat conductor D (left-right asymmetry in the figure). Therefore, as shown in FIG. 4, the flat conductor D has the top portion T protruding toward the concave 24 side of the crank portion forming surface 22a of the convex shape 22 and the most convex type 22 of the crank portion forming surface 24a of the concave shape 24. A phenomenon occurs in which contact is made at two points with the edge portion Er on one side (on the right side in the drawing) protruding to the side, and the top portion T is rotated around the top portion T. In this embodiment, each of the contact surfaces 33a and 35a of the first and second contact members 33 and 35 is formed by an arcuate concave curved surface, and the radius of curvature of the concave curved surface is the flat conductor D. The length is set to correspond to the distance from the contact portion with the top portion T of the convex shape 22 to one end portion (right end portion in the drawing). Therefore, when the flat conductor D rotates about the top portion T of the convex conductor 22, the locus of the arc drawn by both ends of the flat conductor D is the contact surfaces 33a of the first and second contact members 33 and 35. , 35a along the concave curved surface. As a result, even if the flat conductor D rotates, the first and second contact members 33 and 35 can maintain the state in which the flat conductor D is in contact with and held on the contact surfaces 33a and 35a, and the flat conductor D is flat. It is possible to prevent the conductor D from being displaced in the longitudinal direction.

Here, since the top portion T of the convex shape 22 is formed at a position shifted to one side (left side in the drawing) with respect to the center of the crank portion forming surface 22a, the flat conductor D rotates about the top portion T. Sometimes, the radius of the arc drawn by one end (right end in the figure) and the radius of the arc drawn by the other end (left end in the figure) are different. In this embodiment, the radius of curvature of each of the contact surfaces 33a and 35a (concave curved surface) of the first and second contact members 33 and 35 is from the contact portion with the top T of the convex type 22 in the flat conductor D. Strictly speaking, the radius of curvature of the contact surface 35a (concave curved surface) of the second contact member 35 is centered on the top T because the length corresponds to the distance to one end (right end in the figure). The other end of the flat conductor D (the left end in the figure) does not match the radius of the arc drawn. However, since the second contact member 35 is a movable member and is urged toward the first contact member 33 by the urging member 36, the radius of curvature and the flat angle of the contact surface 35a of the second contact member 35. Even if there is a slight deviation from the radius of the arc drawn by the other end of the conductor D (left end in the figure), the other end of the flat conductor D (in the figure) at the contact surface 35a of the second contact member 35. , The left end) can be kept in good contact with each other.

When the flat conductor D rotates about the top T of the convex shape 22, as shown in FIG. 5, the flat conductor D eventually has three points, the top T of the convex shape 22 and the edge portions Er and El on both sides of the concave shape 22. Be supported. Then, the coil forming apparatus 20 further moves the concave conductor D toward the convex mold 22 in a state where the flat conductor D is supported at three points, and moves the flat conductor D in the width direction on the crank portion forming surfaces 22a and 24a. By pressurizing, as shown in FIG. 6, the crank portion is formed by bending and molding into a crank shape.

The coil forming apparatus 20 of the present embodiment described above includes a convex type 22 and a concave type 24 having crank portion forming surfaces 22a and 24a formed in an asymmetrical shape with respect to the center in a plan view including a flat conductor D. Further, in the coil forming apparatus 20, the first positioning member 32 including the first contact member 33 that contacts one end of the flat conductor D, and the first contact member 33 and the contact surfaces 33a and 35a of each other face each other. A second contact member 35 that is arranged in such a manner and abuts on the other end of the flat conductor D, and a urging member 36 that urges the second contact member 35 toward the first contact member 33 side. 2 Positioning member 34 and. Further, the contact surfaces 33a and 35a of the first and second contact members 33 and 35 are formed by an arcuate concave curved surface, and the radius of curvature of the concave curved surface is convex during bending molding on the flat conductor D. The length is determined to correspond to the distance from the contact portion in contact with the top portion T of the mold 22 to one end portion. As a result, the flat conductor D is brought into contact with the top T of the convex mold 22 and the edge portion Er on one side of the concave mold 24 at the time of bending molding, and even if the flat conductor D is rotated around the top T, the flat conductor D Both ends of the first and second contact members 33, 35 can be kept in contact with and held against the contact surfaces 33a, 35a. As a result, the positional deviation of the flat conductor D in the longitudinal direction can be suppressed, and the molding accuracy at the time of bending molding can be further improved.

In the embodiment, the contact surface 33a of the first contact member 33 that contacts one end of the flat conductor D and the contact surface 35a of the second contact member 35 that contacts the other end of the flat conductor D are the same. It was assumed to be formed by a concave curved surface with a radius of curvature of. However, both contact surfaces 33a and 35a may be formed by concave curved surfaces having different radii of curvature. That is, the radius of curvature of the contact surface 33a of the first contact member 33 is set to a length corresponding to the distance between the contact portion of the flat conductor D with the top portion T of the convex type 22 and the one end portion. The radius of curvature of the contact surface 35a of the contact member 35 may be set to a length corresponding to the distance between the contact portion of the flat conductor D with the top portion T of the convex type 22 and the other end portion.

The correspondence between the main elements of the examples and the main elements of the invention described in the column of means for solving the problem will be described. In the embodiment, the convex type 22 corresponds to the "convex type", the concave type 24 corresponds to the "concave type", the first positioning member 32 corresponds to the "first positioning member", and the first contact member 33 corresponds to the "concave type". The second contact member 34 corresponds to the "second positioning member", the second contact member 35 corresponds to the "second contact member", and the urging member 36 corresponds to the "second contact member". Corresponds to "a urging member".

Regarding the correspondence between the main elements of the examples and the main elements of the invention described in the column of means for solving the problem, the invention described in the column of the means for solving the problem in the examples is carried out. Since it is an example for specifically explaining the form for solving the problem, the elements of the invention described in the column of means for solving the problem are not limited. That is, the interpretation of the invention described in the column of means for solving the problem should be performed based on the description in the column, and the examples are the inventions described in the column of means for solving the problem. It is just a concrete example.

Although the embodiments for carrying out the present invention have been described above with reference to examples, the present invention is not limited to these examples, and various embodiments are used without departing from the gist of the present invention. Of course, it can be done.

The present invention can be used in the manufacturing industry of coil molding equipment.

10 Motor stator, 12 stator core, 13 segment coil, 13a straight part, 13b shoulder part, 13c crank part, 14 stator coil, 20 coil molding device, 22 convex type, 22a crank part molding surface, 24 concave type, 24a crank Part molding surface, 30 positioning device, 32 first positioning member, 33 first contact member, 33a first contact surface, 34 second positioning member, 35 second contact member, 35a second contact surface, 36 Force member, D flat conductor, T top, Er, El edge.

Claims (1)

A coil molding apparatus for bending and molding the flat conductor by sandwiching the flat conductor in the width direction using convex and concave molds having molding surfaces asymmetrical with respect to the center in a plan view including a flat conductor extending linearly.
A first positioning member including a first contact member that contacts one end of the flat conductor, and
A second contact member which is arranged so that the first contact member and the contact surfaces of each other face each other and abuts on the other end of the flat conductor, and the second contact member on the side of the first contact member. A second positioning member that includes a urging member that urges the conductor toward the surface, and positions the flat conductor together with the first positioning member by sandwiching the flat conductor in the longitudinal direction.
With
Each contact surface of the first and second contact members is formed by an arcuate concave curved surface.
The radius of curvature of the concave curved surface is set to a length corresponding to the distance from the contact portion to the end portion of the flat conductor that comes into contact with the top of the convex shape during the bending molding.
Molding equipment for coils.

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