JP6826188B2 - Method of joining electric conductors and their equipment - Google Patents

Description

The present invention relates to a method for joining electric conductors for joining the legs of electric conductors inserted into slots formed in a stator core, and an apparatus thereof.

Conventionally, it is known that a stator is formed by inserting electric conductors into two of a plurality of slots formed along the circumferential direction of a ring-shaped stator core. Here, the electrical conductor has a substantially U-shape or a substantially I-shape, and therefore has at least one leg. The leg is inserted into the slot and the tip protrudes from the slot. Since the plurality of slots are formed radially, for example, one leg protrudes from the slot on the outer peripheral side, and the leg of another electric conductor is formed from the slot on the inner peripheral side adjacent to each other in the radial direction. Protrude.

By joining the protruding legs to each other, an electric path is formed between the electric conductors. As the joining method, for example, arc welding is adopted as described in Japanese Patent Application Laid-Open No. 2000-350422.

In the case of arc welding, only two legs can be joined in one joining operation. That is, arc welding must be repeated in order to perform all joining. Moreover, in this case, there is a possibility that the quality may vary from hit to point, so it is necessary to avoid this and perform repairs to make the quality substantially equal. As described above, in arc welding, a problem that it is not easy to obtain a stator efficiently and that it is complicated has become apparent.

A general object of the present invention is to provide a method for joining electric conductors capable of improving the production efficiency of a stator.

A main object of the present invention is to provide a method for joining an electric conductor that can simplify the joining work.

Another object of the present invention is to provide a joining device for joining electric conductors.

According to one embodiment of the present invention, two legs of electric conductors inserted into a plurality of slots provided in the circumferential direction of a ring-shaped stator core projecting from the stator core and adjacent to each other in the radial direction. It is a method of joining electric conductors that joins
A step of arranging an electromagnetic coil in a circumferential shape on at least one of the inner peripheral side and the outer peripheral side of the stator core.
By energizing the electromagnetic coil, the two adjacent legs are brought into contact with each other, and the two abutted legs are joined to each other.
A method of joining an electric conductor having the above is provided.

According to another embodiment of the present invention, two legs of electric conductors inserted into a plurality of slots provided in the circumferential direction of a ring-shaped stator core protruding from the stator core and adjacent to each other in the radial direction. It is a joining device for electric conductors that joins parts together.
An electromagnetic coil arranged on at least one of the inner peripheral side and the outer peripheral side of the stator core,
A current supply unit that supplies current to the electromagnetic coil and
An electric conductor joining device having the above is provided.

That is, in the present invention, the electromagnetic coils are arranged in a circumferential shape on at least one of the inner peripheral side and the outer peripheral side of the stator core, and the electromagnetic coils are energized. At this time, a strong magnetic field is generated in the vicinity of the electromagnetic coil and the legs. Therefore, an electromagnetic force is generated in the direction of pushing the leg portion close to the electromagnetic coil toward another adjacent leg portion. The leg that receives the electromagnetic force bends and comes into contact with another leg adjacent to this leg at supersonic speed. In the legs that are in contact with each other at supersonic speeds in this way, the oxide film is scattered from the surface to be joined, and atoms are diffused from the exposed base metal to each other. As a result, a metallurgical joint is made.

This phenomenon occurs simultaneously between all the legs on which the electromagnetic force acts and all the legs adjacent to the legs. That is, by configuring as described above, it is possible to join a plurality of legs at the same time. Moreover, the bending and contact, and further, the joining proceeds rapidly in a short time. Therefore, the time required for joining is remarkably shortened, so that the stator can be efficiently produced. In the end, the production efficiency of the stator can be improved.

Moreover, the magnitude of the magnetic field generated in the vicinity of each leg and the magnitude of the electromagnetic force acting on each leg are substantially the same. For this reason, there is no need to perform repairs because there is no concern that the quality will vary from joint to joint. This simplifies the joining work.

The legs can be brought into contact with each other, for example, by generating an induced current in one of two adjacent legs and bringing the one closer to the other by the electromagnetic force generated by the induced current.

Alternatively, a movable member may be provided between the electromagnetic coil and the electric conductor, and the movable member may be displaced to press the legs so that the legs are brought into contact with each other.

When one of the two legs approaches the other, it is preferable to provide a support member that supports the other from the side opposite to the portion where the one abuts. As a result, the legs to be joined are positioned. That is, the positions of the joints can be aligned. Further, since the support member supports the contact points between the legs, the impact when the legs come into contact with each other is not mitigated. Therefore, the collision energy at the time of contact is converted into the thermal energy for joining and effectively consumed.

According to the present invention, the electromagnetic coils are arranged in a circumferential shape on at least one of the inner peripheral side and the outer peripheral side of the stator core so that the electromagnetic coils are energized, so that the leg portion close to the electromagnetic coil is energized. , An electromagnetic force is generated in the direction of pushing this leg toward another adjacent leg. The leg that receives this electromagnetic force bends and comes into contact with another leg adjacent to the leg to join.

Since this phenomenon occurs simultaneously between all the legs on which the electromagnetic force acts and all the legs adjacent to the legs, it is possible to join a plurality of legs at the same time. As a result, the time required for joining is significantly shortened, and the production efficiency of the stator is improved.

Moreover, since the magnitude of the magnetic field generated in the vicinity of each leg and the magnitude of the electromagnetic force acting on each leg are substantially the same, it is possible to avoid variations in quality at each joint. Therefore, no repair is required. By this amount, the joining work can be simplified.

It is a general schematic partial vertical cross-sectional view which showed together the stator core through which a segment was passed and the joining apparatus which concerns on 1st Embodiment of this invention. It is a general schematic partial vertical cross-sectional view which shows the state which lowered the outer side magnetic flux concentrator which constitutes the joining device of FIG. 1 and made it enter into the outer side electromagnetic coil. It is a schematic horizontal sectional view of the main part which shows the positional relationship of the stator core, the outer side magnetic flux concentrator, and the outer side electromagnetic coil in the state of FIG. It is an enlarged partial vertical sectional view of a main part which shows the state which the outermost leg part and the adjacent leg part on the inner peripheral side are brought into contact with each other and are joined. It is a general schematic partial vertical cross-sectional view which showed together the stator core through which a segment was passed and the joining apparatus which concerns on 2nd Embodiment of this invention. FIG. 5 is a schematic partial vertical cross-sectional view showing a state in which the inner magnetic flux concentrator constituting the joining device of FIG. 5 is lowered and the inner electromagnetic coil is surrounded. FIG. 6 is a schematic horizontal sectional view of a main part showing the positional relationship between the inner side electromagnetic coil, the inner side magnetic flux concentrator, and the stator core in the state of FIG. It is an enlarged front view of the main part which shows the state which the innermost leg part and the adjacent leg part on the outer peripheral side are brought into contact with each other and are joined. It is a general schematic partial vertical cross-sectional view which showed together the stator core through which a segment was passed and the joining apparatus which concerns on 3rd Embodiment of this invention. The inner magnetic flux concentrator and the outer magnetic flux concentrator constituting the bonding device of FIG. 9 are lowered, the inner magnetic flux concentrator surrounds the inner magnetic flux concentrator, and the outer magnetic flux concentrator enters the outer electromagnetic coil. It is a general schematic partial vertical sectional view which shows the state which made it made. FIG. 10 is a schematic horizontal sectional view of a main part showing the positional relationship between the inner side electromagnetic coil, the inner side magnetic flux concentrator, the stator core, the outer side magnetic flux concentrator, and the outer side electromagnetic coil in the state of FIG. The outermost leg and the adjacent leg on the inner peripheral side thereof are brought into contact with each other for joining, and the innermost leg and the adjacent leg on the outer peripheral side thereof are brought into contact with each other for joining. It is the enlarged front view of the main part which shows the state which is performing. A main part showing the positional relationship between the stator core, the outer magnetic flux concentrator, and the outer electromagnetic coil when the outer magnetic flux concentrator constituting the joining device according to the fourth embodiment of the present invention is inserted into the outer electromagnetic coil. It is a schematic horizontal sectional view. It is an enlarged front view of the main part which shows the state which the leg part on the outer peripheral side and the leg part adjacent to each other on the inner peripheral side are brought into contact with each other to be joined.

Hereinafter, the method for joining an electric conductor according to the present invention will be described in detail with reference to the accompanying drawings with reference to preferred embodiments in relation to a joining device for carrying out the method. In the following, the electric conductor is also referred to as a “segment”.

FIG. 1 is an overall schematic partial vertical cross-sectional view showing the stator core 12a through which the segment 10 is passed and the joining device 14a according to the first embodiment. Briefly explaining the segment 10 and the stator core 12a, first, the segment 10 is formed by connecting two leg portions 16 via a turn portion 18 curved by substantially 180 °, and thus forms a substantially U shape.

On the other hand, the stator core 12a has an annular shape (see FIG. 3), and two slots 20 are formed in each of the inner peripheral side edge portion and the outer peripheral side edge portion along the radial direction. That is, four slots 20 are arranged along the radial direction. Assuming that these four slots are a set of slot groups 22a, in the first embodiment, for example, 24 sets of slot groups 22a are arranged radially.

The legs 16 of the four segments 10 are individually inserted into the four slots 20 constituting the set of slot groups 22a, and project upward in FIG. 1. That is, the segment 10 is held by the stator core 12a in a posture in which the turn portion 18 is downward and the leg portion 16 is upward.

The joining device 14a according to the first embodiment induces when the support base 24a that accommodates and supports the stator core 12a, the outer-side electromagnetic coil 26 that constitutes the joining mechanism, and the outer-side electromagnetic coil 26 are energized. It has an outer magnetic flux concentrator 28 in which an electric current is generated and an electromagnetic force F1 is generated.

The support base 24a is a hollow body having a large-diameter accommodating hole 30 formed therein, and a stator step portion 32 for supporting the outer peripheral edge portion of the lower end surface of the stator core 12a is formed inside the accommodating hole 30. .. The step between the stator step portion 32 and the bottom surface of the accommodating hole 30 is set to be slightly larger than the protruding height of the turn portion 18. Therefore, it is avoided that the turn portion 18 comes into contact with the inner bottom surface.

In the support base 24a, an outer coil step portion 34 is formed in the vicinity of the opening of the accommodating hole 30. The outer side electromagnetic coil 26 is supported by the outer side coil step portion 34.

A current supply unit 48 (see FIG. 4) in which a capacitor 40, a switch 42, a resistor 44, and an inductance 46 are connected in series is electrically connected to the outer electromagnetic coil 26. When the switch 42 is turned on, the electrons accumulated in the capacitor 40 move and a current is supplied to the outer electromagnetic coil 26. That is, the outer electromagnetic coil 26 is energized.

The outer magnetic flux concentrator 28 has a ring shape (see FIG. 3), and its outer diameter is slightly smaller than the inner diameter of the outer electromagnetic coil 26. Further, the height of the outer magnetic flux concentrator 28 is substantially equal to the height of the outer electromagnetic coil 26. Therefore, the outer magnetic flux concentrator 28 can enter the hollow inside of the outer electromagnetic coil 26, and when it enters, it is surrounded by the outer electromagnetic coil 26.

An annular protrusion 50 for outer is formed so as to project toward the inner peripheral side at the lower end of the outer magnetic flux concentrator 28. As will be described later, the outer annular protrusion 50 faces the outermost leg 16, and the facing leg 16 is bent by the electromagnetic force F1.

The outer magnetic flux concentrator 28 configured in this way is held by the concentrator holder 56a together with the block body 54a (support member) having the support portion 52. Although two block bodies 54a are shown in FIG. 1, one block body 54a is actually assigned to one set of slot groups 22a (see FIG. 3). That is, in this case, 24 block bodies 54a are arranged on the same circumference.

The lower end of the block body 54a has a substantially H shape in a plan view (see FIG. 3), and the two long side portions extend from the inner peripheral side to the outer peripheral side of the stator core 12a, and a set of slot groups 22a. They face each other with (4 slots 20) in between. These two long side portions serve as guide portions. On the other hand, the short side portion that is interposed between the two long side portions and extends in the direction orthogonal to the longitudinal direction of these long side portions constitutes the support portion 52, and is outside the set of slot groups 22a. It is interposed between the two on the peripheral edge side and the two on the inner peripheral edge side.

The concentrator holder 56a is further held by a disk-shaped holder 58 having a disk-shaped base and having a substantially inverted T-shaped cross section. The disk-shaped holder 58 is connected to, for example, an elevating rod (neither shown) of a hydraulic cylinder, and descends or ascends as the elevating rod advances (descends) or retracts (ascends). Along with this, the concentrator holder 56a, the outer magnetic flux concentrator 28, and the block body 54a are integrally lowered or raised.

The joining device 14a according to the first embodiment is basically configured as described above, and then, its action and effect will be described in relation to the joining method of the segment 10 according to the present embodiment. To do.

To obtain a stator, first select from two different slots 20 (typically one selected from any slot group 22a) and another slot group 22a from a plurality of slots 20 provided in the stator core 12a. The two legs 16 of one segment 10 are individually inserted into the one). This is repeated, and the insertion of a predetermined number of segments 10 into the slots 20 is completed. Of course, a plurality of segments 10 may be inserted into the slot 20 at once.

Next, as shown in FIG. 2, the stator core 12a is inserted into the accommodating hole 30 of the support base 24a so that the turn portion 18 faces downward and the leg portion 16 faces upward, and the stator step portion 32 To support. As described above, at this time, the turn portion 18 does not come into contact with the inner bottom surface of the accommodating hole 30. After or before the stator core 12a is accommodated in the accommodating hole 30 in this way, the outer side electromagnetic coil 26 is supported by the outer side coil step portion 34.

Next, the hydraulic cylinder is urged and the elevating rod is advanced. As a result, the centralizer holder 56a, the outer magnetic flux concentrator 28, and the block body 54a are lowered integrally with the disk-shaped holder 58. When the disk-shaped holder 58 descends to the bottom dead center, the outer magnetic flux concentrator 28 enters the inside of the outer electromagnetic coil 26. That is, as shown in FIGS. 2 and 3, the outer magnetic flux concentrator 28 is surrounded by the outer electromagnetic coil 26. Further, the guide portion of the block body 54a sandwiches the four legs 16 protruding from one set of slot groups 22a (four slots 20), and the support portion 52 protrudes from the same slot group 22a. It is interposed between the two legs 16 on the side and the two legs 16 on the inner peripheral edge side.

Next, the outer electromagnetic coil 26 is energized. Specifically, the switch 42 (see FIG. 4) is switched ON. As a result, the electric charge accumulated in the capacitor 40 moves, and as a result, the current (i) flows. In the current supply unit 48 shown in FIG. 4, the current flows from the resistor 44 to the inductance 46 side. Therefore, the current in the outer electromagnetic coil 26 goes from the back to the front of the paper on the left side of FIG. 4 and from the front to the back of the paper on the right side.

As such a current flows in the outer electromagnetic coil 26, an induced current is generated in the outer peripheral portion of the outer magnetic flux concentrator 28 facing the inner circumference of the outer electromagnetic coil 26. The direction of the induced current is opposite to that in the outer electromagnetic coil 26. For example, the left side of FIG. 4 is from the front to the back of the paper surface, and the right side is from the back to the front of the paper surface.

Further, an induced current is generated in the inner peripheral portion of the outer magnetic flux concentrator 28, in other words, in the outer annular protrusion 50, in the direction opposite to the outer peripheral portion of the outer magnetic flux concentrator 28. Further, an induced current is generated in the outermost leg portion 16 facing the outer annular protrusion 50 in the opposite direction to the outer annular protrusion 50. That is, the direction of the induced current in the inner peripheral portion of the outer magnetic flux concentrator 28 is the same as the direction of the current in the outer electromagnetic coil 26, and the direction of the induced current in the outermost leg 16 is the outer magnetic flux concentrator. It is the same as the outer peripheral portion of 28.

Then, a strong magnetic field is formed in the vicinity of the outermost leg portion 16. The larger the height of the outer electromagnetic coil 26, the larger the induced current flowing through the outer annular protrusion 50, and as a result, a strong magnetic field is formed on the outermost leg 16, which is preferable. .. Due to this strong magnetic field and the induced current generated in the outermost leg 16 as described above, a large electromagnetic force F1 is generated from the outer peripheral side to the inner peripheral side of the stator core 12a according to Fleming's left-hand rule. .. Due to this electromagnetic force F1, the outermost leg portion 16 bends so as to approach the leg portion 16 on the inner peripheral side adjacent to the leg portion 16. At the time of this approach, the leg portion 16 is guided to the long side portion of the block body 54a that sandwiches the leg portion 16.

As a result, the inner peripheral side wall of the outermost leg portion 16 comes into contact with the outer peripheral side wall of the leg portion 16 on the inner peripheral side at supersonic speed. At this time, the support portion 52 of the block body 54a supports the inner peripheral wall side of the leg portion 16 on the inner peripheral side. That is, the support portion 52 supports the inner peripheral side wall opposite to the outer peripheral side wall where the outermost leg portion 16 approaches and abuts on the inner peripheral side leg portion 16. Therefore, the legs 16 on the inner peripheral side maintain their original positions before and after the contact.

The oxide film is scattered from the inner peripheral side wall of the outermost leg portion 16 and the outer peripheral side wall of the outer peripheral side leg portion 16 that are in contact with each other at supersonic speed. As a result, the base metal is exposed and atoms are diffused from the base metal toward each other. Further, since the induced current is generated in the outermost leg portion 16, Joule heat is generated at the contact portion between the leg portions 16. Further, since the outermost leg portion 16 bends and approaches the inner peripheral side leg portion 16 at a high speed, collision energy is generated at the time of contact, and this collision energy is converted into thermal energy. Moreover, since the support portion 52 of the block body 54a supports the leg portion 16 on the inner peripheral side, the impact at the time of contact is not mitigated. Therefore, the conversion efficiency from collision energy to thermal energy is increased. In this way, the oxide film is scattered at the contact point, and Joule heat and large heat energy are generated. For this reason, the legs 16 are metallurgically joined to each other at substantially the same time as the contact. The bending, abutting and joining is completed in less than 1 second, typically 0.5 seconds or less.

The above phenomenon proceeds simultaneously in all of the 24 sets of slot groups 22a. That is, according to the first embodiment, all the outermost leg portions 16 and all the leg portions 16 adjacent to each other on the inner peripheral side thereof can be joined at the same time in one operation. Therefore, the time required to obtain the stator is remarkably shortened, so that the production efficiency of the stator can be improved.

Moreover, since the induced currents are generated substantially the same throughout, it is possible to avoid a large difference in quality for each joint. Therefore, no repair is required, and the joining work is simplified.

Next, the joining device 14b according to the second embodiment will be described. The same components as those shown in FIGS. 1 to 4 are designated by the same reference numerals, and detailed description thereof will be omitted. The same applies to the subsequent third and fourth embodiments.

As shown in FIG. 5, the joining device 14b according to the second embodiment includes a support base 24b that accommodates and supports the stator core 12a, an inner electromagnetic coil 70 that constitutes the joining mechanism, and the inner electromagnetic coil 70. It has an inner magnetic flux concentrator 72 in which an induced current is generated when energization is applied and an electromagnetic force F2 is generated.

An annular recess 73 is formed in the support base 24b, and a stator step portion 32 is formed in the vicinity of the opening of the annular recess 73. Similar to the first embodiment, the step between the stator step portion 32 and the inner bottom surface of the annular recess 73 is set to be slightly larger than the protruding height of the turn portion 18. Therefore, it is avoided that the turn portion 18 comes into contact with the inner bottom surface.

An inner coil step portion 76 is formed at the center of the annular recess 73. The inner side electromagnetic coil 70 is supported by the inner side coil step portion 76.

Although not shown in order to simplify the drawing and facilitate understanding, the inner side electromagnetic coil 70 has a current in which a capacitor 40, a switch 42, a resistor 44, and an inductance 46 are connected in series as in the first embodiment. The supply unit 48 is electrically connected (see FIG. 4). When the switch 42 is turned on, the electrons accumulated in the capacitor 40 move and a current flows through the inner electromagnetic coil 70.

The inner magnetic flux concentrator 72 has an annular shape (see FIG. 7), and its outer diameter is slightly larger than the inner diameter of the inner electromagnetic coil 70. Further, the height of the inner magnetic flux concentrator 72 is substantially equal to the height of the inner electromagnetic coil 70. Therefore, the inner side electromagnetic coil 70 can enter the hollow inside of the lowered inner side magnetic flux concentrator 72, and when it enters, it is surrounded by the inner side magnetic flux concentrator 72.

An annular protrusion 74 for an inner is formed so as to project toward the outer peripheral side substantially in the middle of the inner magnetic flux concentrator 72 in the height direction. In the second embodiment, the inner annular protrusion 74 faces the innermost leg portion 16, and the facing leg portion 16 is bent by the electromagnetic force F2 in the same manner as described above.

The inner magnetic flux concentrator 72 is held in the concentrator holder 56b together with the block body 54a. Although two block bodies 54a are shown in FIG. 5, in reality, 24 block bodies 54a are arranged on the same circumference.

Since the block body 54a and the disk-shaped holder 58 are the same as those in the first embodiment, detailed description thereof will be omitted.

The joining device 14b according to the second embodiment is basically configured as described above, and the effects thereof will be described next.

Similar to the first embodiment, after inserting the leg portions 16 of a predetermined number of segments 10 into each slot 20, the turn portion 18 is in a downward position and the leg portion 16 is in an upward position, as shown in FIG. As described above, the stator core 12a is supported by the stator step portion 32 of the support base 24b. As a result, the stator core 12a is positioned to cover the annular recess 73. As described above, the turn portion 18 does not come into contact with the inner bottom surface of the annular recess 73. After or before the stator core 12a is supported by the support base 24b in this way, the inner side electromagnetic coil 70 is supported by the inner side coil step portion 76.

Next, the hydraulic cylinder is urged and the elevating rod is advanced. As a result, the centralizer holder 56b, the inner magnetic flux concentrator 72, and the block body 54a are lowered integrally with the disk-shaped holder 58. As the disk-shaped holder 58 descends to the bottom dead center, the inner magnetic flux concentrator 72 surrounds the inner electromagnetic coil 70. That is, as shown in FIGS. 6 and 7, the inner side electromagnetic coil 70 enters the inside of the inner side magnetic flux concentrator 72. Further, the long side portion of the block body 54a serving as the guide wall sandwiches the four legs 16 protruding from the set of slot groups 22a (four slots 20), and the support portion 52 is from the same slot group 22a. It is interposed between the two protruding leg portions 16 on the outer peripheral edge side and the two leg portions 16 on the inner peripheral edge side.

Next, the switch 42 constituting the current supply unit 48 is switched to ON, and the inner side electromagnetic coil 70 is energized. As a result, an induced current is applied to the inner peripheral portion of the inner magnetic flux concentrator 72, the outer peripheral portion of the inner magnetic flux concentrator 72 (inner annular protrusion 74), and the innermost leg 16 facing the inner annular protrusion 74. Are generated respectively. At the same time, a strong magnetic field is formed in the vicinity of the innermost leg portion 16.

Due to this strong magnetic field and the induced current generated in the innermost leg 16, a large electromagnetic force F2 from the inner peripheral side to the outer peripheral side of the stator core 12a is generated according to Fleming's left-hand rule, as shown in FIG. Occur. Due to this electromagnetic force F2, the innermost leg portion 16 bends so as to approach the leg portion 16 on the outer peripheral side adjacent to the leg portion 16. At the time of this approach, the leg portion 16 is guided to the long side portion of the block body 54a that sandwiches the leg portion 16.

As a result, the outer peripheral side wall of the innermost leg portion 16 abuts on the inner peripheral side wall of the outer peripheral side leg portion 16 at supersonic speed, and the outer peripheral side wall of the innermost leg portion 16 and the outer peripheral side leg portion 16 The oxide film scatters from the inner peripheral side wall and the atoms diffuse toward each other. At this time, the support portion 52 of the block body 54a supports the outer peripheral wall side of the leg portion 16 on the outer peripheral side. That is, the support portion 52 supports the inner peripheral side wall opposite to the inner peripheral side wall where the innermost leg portion 16 approaches and abuts on the outer peripheral side leg portion 16. Therefore, the legs 16 on the outer peripheral side maintain their original positions before and after the contact.

Further, since the induced current is generated in the innermost leg portion 16, Joule heat and thermal energy are generated at the contact points between the leg portions 16. Due to the scattering of the oxide film, the diffusion of atoms, and the Joule heat and thermal energy, the legs 16 are metallurgically bonded to each other at substantially the same time as the contact. Similar to the above, the bending of the innermost leg 16 and the contact and joining of the two legs 16 are completed in 1 second or less, typically 0.5 seconds or less.

Of course, the above phenomenon proceeds simultaneously in all of the 24 sets of slot groups 22a. That is, according to the second embodiment, all the innermost leg portions 16 and all the adjacent leg portions 16 on the outer peripheral side thereof can be joined at the same time in one operation. Moreover, it is avoided that the quality differs greatly for each joint. That is, the production efficiency of the stator can be improved, and the joining work can be simplified.

Next, the joining device 14c according to the third embodiment shown in FIG. 9 will be described. The joining device 14c is composed of a support base 24c that accommodates and supports the stator core 12a, an outer side electromagnetic coil 26 and an inner side electromagnetic coil 70 that form a joining mechanism, and the outer side electromagnetic coil 26 and an inner side electromagnetic coil 70. It has an outer side magnetic flux concentrator 28 and an inner side magnetic flux concentrator 72 that generate an electromagnetic force.

A housing hole 30 is formed in the support base 24c, and a stator step portion 32 is formed in the vicinity of the inner bottom surface of the housing hole 30. Similar to the first embodiment, the step between the stator step portion 32 and the inner bottom surface of the accommodating hole 30 is set to be slightly larger than the protruding height of the turn portion 18. Therefore, it is avoided that the turn portion 18 comes into contact with the inner bottom surface.

At the center of the accommodating hole 30, an inner coil step portion 76 extending from the inner bottom surface is provided. The inner side electromagnetic coil 70 is supported by the inner side coil step portion 76. Further, an outer coil step portion 34 for supporting the outer electromagnetic coil 26 is formed in the vicinity of the opening of the accommodating hole 30.

Although not shown for simplification of the drawing and easy understanding, a current supply in which a capacitor 40, a switch 42, a resistor 44, and an inductance 46 are connected in series to the outer side electromagnetic coil 26 and the inner side electromagnetic coil 70. The unit 48 is electrically connected. The current supply unit 48 may be common to the outer side electromagnetic coil 26 and the inner side electromagnetic coil 70, or may be separate.

In this case, the concentrator holder 56c is located on the inner peripheral side of the first annular wall portion 80 for holding the outer magnetic flux concentrator 28 and the inner peripheral side magnetic flux concentrator 72. It has a second ring wall portion 82 to be held. The outer annular protrusion 50 of the outer magnetic flux concentrator 28 held by the first annular wall 80 and the inner annular protrusion 74 of the inner magnetic flux concentrator 72 held by the second annular wall 82. Are located at approximately the same height.

Further, in this case, the block body 54a is arranged between the first annular wall portion 80 and the second annular wall portion 82. Although two block bodies 54a are shown in FIG. 9, 24 block bodies 54a are actually arranged on the same circumference as described above.

Since the block body 54a and the disk-shaped holder 58 are the same as those in the first embodiment and the second embodiment, detailed description thereof will be omitted.

The joining device 14c according to the third embodiment is basically configured as described above, and the effects thereof will be described next.

Similar to the first embodiment, after inserting the leg portions 16 of a predetermined number of segments 10 into each slot 20, the turn portion 18 is in a downward position and the leg portion 16 is in an upward position, as shown in FIG. As described above, the stator core 12a is inserted into the accommodating hole 30 and supported by the stator step portion 32. As a result, the stator core 12a is positioned to cover the accommodating hole 30. As described above, the turn portion 18 does not come into contact with the inner bottom surface of the accommodating hole 30. After or before the stator core 12a is accommodated in the accommodating hole 30 in this way, the outer side electromagnetic coil 26 and the inner side electromagnetic coil 70 are supported by the inner side coil step portion 76 and the outer side electromagnetic coil 26, respectively.

Next, the hydraulic cylinder is urged and the elevating rod is advanced. As a result, the centralizer holder 56c, the outer magnetic flux concentrator 28, the inner magnetic flux concentrator 72, and the block body 54a are lowered integrally with the disk-shaped holder 58. As the disk-shaped holder 58 descends to the bottom dead center, the outer-side magnetic flux concentrator 26 surrounds the outer-side magnetic flux concentrator 28, and the inner-side magnetic flux concentrator 72 surrounds the inner-side electromagnetic coil 70. That is, as shown in FIGS. 10 and 11, the outer side magnetic flux concentrator 28 enters the inside of the outer side electromagnetic coil 26, and the inner side electromagnetic coil 70 enters the inside of the inner side magnetic flux concentrator 72.

Further, the guide portion of the block body 54a sandwiches the four legs 16 protruding from one set of slot groups 22a (four slots 20), and the support portion 52 protrudes from the same slot group 22a. It is interposed between the two legs 16 on the side and the two legs 16 on the inner peripheral edge side.

Next, the switch 42 constituting the current supply unit 48 is switched to ON, and the outer side electromagnetic coil 26 and the inner side electromagnetic coil 70 are energized. As a result, an induced current is applied to the outer peripheral portion of the outer magnetic flux concentrator 28, the inner peripheral portion of the outer magnetic flux concentrator 28 (outer annular protrusion 50), and the outermost leg portion 16 facing the outer annular protrusion 50. Are generated respectively. At the same time, an induced current is also applied to the inner peripheral portion of the inner magnetic flux concentrator 72, the outer peripheral portion of the inner magnetic flux concentrator 72 (inner annular protrusion 74), and the innermost leg 16 facing the inner annular protrusion 74. Are generated respectively. On the other hand, a strong magnetic field is formed in the vicinity of the outermost leg 16 and the innermost leg 16, respectively.

After that, as in the first embodiment and the second embodiment, according to Fleming's left-hand rule, a large electromagnetic force F1 from the outer peripheral side to the inner peripheral side of the stator core 12a and a large electromagnetic force from the inner peripheral side to the outer peripheral side F2 and F2 occur at the same time. Due to these electromagnetic forces F1 and F2, as shown in FIG. 12, the outermost leg portion 16 bends toward the inner peripheral side leg portion 16 adjacent to the leg portion 16 and is bent toward the innermost leg portion 16. The leg portion 16 of the above bends so as to approach the leg portion 16 on the outer peripheral side adjacent to the leg portion 16. At the time of this approach, the leg portion 16 is guided to the long side portion of the block body 54a that sandwiches the leg portion 16.

As a result, the inner peripheral side wall of the outermost leg portion 16 abuts on the outer peripheral side wall of the inner peripheral side leg portion 16 at supersonic speed, and the outer peripheral side wall of the innermost leg portion 16 is brought into contact with the outer peripheral side wall of the outer peripheral side leg portion 16. It abuts at supersonic speed on the inner peripheral side wall of the. At this time, the support portion 52 supports the leg portions 16 adjacent to the inner peripheral side of the outermost leg portion 16 and the leg portions 16 adjacent to the outer peripheral side of the innermost leg portion 16. Therefore, these two legs 16 maintain their original positions before and after the contact.

Further, since induced currents are generated in the outermost leg 16 and the innermost leg 16, Joule heat and thermal energy are generated at the contact points between the legs 16. Due to the scattering of the oxide film and the diffusion of atoms due to the contact at supersonic speed, and the Joule heat and thermal energy, the two adjacent legs 16 are metallically bonded to each other at substantially the same time as the contact. Similar to the above, the bending of the outermost leg 16 and the innermost leg 16 and the contact and joining of the two adjacent legs 16 are 1 second or less, typically 0.5 seconds or less. It ends with.

Of course, the above phenomenon proceeds simultaneously in all of the 24 sets of slot groups 22a. That is, according to the third embodiment, all the outermost leg portions 16 and all the leg portions 16 adjacent to each other on the inner peripheral side thereof, and all the innermost leg portions 16 and the adjacent leg portions 16 on the outer peripheral side thereof. All can be joined at the same time in one operation. Moreover, it is avoided that the quality differs greatly for each joint. That is, the production efficiency of the stator can be further improved, and the joining work can be further simplified.

The number of turns of the outer side electromagnetic coil 26 and the inner side electromagnetic coil 70 is the impact at the time of contact acting on the outermost leg 16 and the impact at the time of contact acting on the adjacent legs 16 on the inner peripheral side thereof. Is set to be offset. Therefore, the load on the equipment due to the impact is reduced.

Next, a joining device having a movable member will be described as a fourth embodiment.

FIG. 13 is a schematic horizontal sectional view of a main part showing the stator core 12b through which the segment 10 is passed and the joining device 14d according to the fourth embodiment, and FIG. 14 is an enlarged front view of the main part. is there. In this case, the stator core 12b has an annular shape (see FIG. 13), and there is a slight phase difference between the inner peripheral side edge portion, the inner peripheral side edge portion and the outer peripheral side edge portion, and the outer peripheral side edge portion. Two slots 20 are formed so as to have. In the fourth embodiment, these six are used as a set of slot groups 22b. That is, in these cases, 18 sets of slot groups 22b are arranged radially.

The legs 16 of the six segments 10 are individually inserted into the six slots 20 forming the set of slot groups 22b, and project upward in FIG. 14 (front side of the paper in FIG. 13). Therefore, even in this case, the segment 10 is held by the stator core 12b with the turn portion 18 downward and the leg portion 16 upward.

The joining device 14d includes a support base 24a (see FIG. 1) that accommodates and supports the stator core 12b, an outer-side electromagnetic coil 26 that constitutes the joining mechanism, and an outer-side magnetic flux that produces electromagnetic force by the outer-side electromagnetic coil 26. It has a concentrator 28 and. Since these components, the centralizer holder 56a, and the disk-shaped holder 58 are the same as those in the first embodiment, detailed description thereof will be omitted.

The joining device 14d has an annular guide plate (not shown) provided in the vicinity of the outer annular protrusion 50 of the outer magnetic flux concentrator 28. A plurality of wall portions are formed radially on the annular guide plate, whereby 18 guide portions are separately formed on the annular guide plate. On the inner peripheral side of the guide portion, a retaining wall portion is provided to prevent the focusing member 90 from falling off from the guide portion.

In particular, the focusing member 90 shown in FIG. 14 is slidably housed in each guide portion. On the inner peripheral side of the focusing member 90, a first pressing bar 92, a second pressing bar 94, and a third pressing bar 96 having a substantially T-shape in a plan view are provided. That is, the focusing member 90 collectively supports the first pressing bar 92, the second pressing bar 94, and the third pressing bar 96. The focusing member 90, the first pressing bar 92, the second pressing bar 94, and the third pressing bar 96 are made of a material capable of generating an induced current.

The first pressing bar 92 is the shortest, and its tip faces the outermost leg 16 in the set of slot groups 22b. Further, the tip of the longest third pressing bar 96 faces the fifth leg 16 from the outermost side (second from the innermost side) in the same slot group 22b. The tip of the second pressing bar 94, which has an intermediate length between the first pressing bar 92 and the third pressing bar 96, is the third leg (fourth from the innermost) from the outermost in the same slot group 22b. Facing the unit 16. The tips of the first pressing bar 92, the second pressing bar 94, and the third pressing bar 96 project from the opening formed in the retaining wall portion.

The lower end portion of the block body 54b is set in a shape such that the lengths from the inner peripheral side to the outer peripheral side are gradually different. Specifically, the block body 54b is the first stepped support portion 98a facing the second (fifth from the innermost) leg 16 from the outermost in the same slot group 22b, and the fourth from the outermost (fifth). It has a second stepped support 98b facing the innermost leg 16 and a third stepped support 98c facing the innermost leg 16.

Next, a method of joining the segment 10 using the joining device 14d according to the fourth embodiment will be described.

According to the first embodiment, after inserting the leg portions 16 of a predetermined number of segments 10 into the plurality of slots 20 provided in the stator core 12b, the turn portion 18 is lowered and the legs are as shown in FIG. The stator core 12b is inserted into the accommodating hole 30 of the support base 24a and supported by the stator step portion 32 so that the portion 16 faces upward. It goes without saying that the outer side electromagnetic coil 26 is supported by the outer side coil step portion 34 after or before the stator core 12b is accommodated in the accommodating hole 30.

Further, in order to lower the disc-shaped holder 58, the elevating rod connected to the disc-shaped holder 58 is advanced by urging the hydraulic cylinder. As a result, the centralizer holder 56a, the outer magnetic flux concentrator 28, the annular guide plate, and the block body 54b are lowered integrally with the disk-shaped holder 58. When the disk-shaped holder 58 descends to the bottom dead center, the outer magnetic flux concentrator 28 enters the inside of the outer electromagnetic coil 26. That is, as shown in FIG. 13, the outer magnetic flux concentrator 28 is surrounded by the outer electromagnetic coil 26.

Further, the first-stage support portion 98a, the second-stage support portion 98b, and the third-stage support portion 98c of the block body 54b are the second from the outermost (from the innermost) in the set of slot groups 22b, respectively. It faces the (fifth) leg 16, the fourth (third from the innermost) leg 16 from the outermost, and the innermost leg 16. Further, the tips of the first pressing bar 92, the second pressing bar 94, and the third pressing bar 96 are the outermost leg 16 in the same slot group 22b, the third from the outermost (fourth from the innermost). The leg 16 faces the fifth leg 16 from the outermost (second from the innermost).

After all, the first stepped support portion 98a and the first pressing bar 92 face each other with the outermost leg portion 16 and the leg portions 16 adjacent to each other on the inner peripheral side. Further, the second stepped support portion 98b and the second pressing bar 94 face each other with the third leg portion 16 from the outermost side and the leg portions 16 adjacent to each other on the inner peripheral side sandwiching the third leg portion 16 from the outermost side. The support portion 98c and the third pressing bar 96 face each other with the fifth leg portion 16 from the outermost side and the leg portion 16 adjacent to the support portion 16 (innermost leg portion 16) on the inner peripheral side.

In this state, the outer electromagnetic coil 26 is then energized. That is, the switch 42 (see FIG. 4) is switched ON, and at this time, the electric charge accumulated in the capacitor 40 moves, so that the current is supplied from the current supply unit 48 to the outer electromagnetic coil 26. That is, the outer electromagnetic coil 26 is energized.

As a result, the outer peripheral portion of the outer magnetic flux concentrator 28, the inner peripheral portion of the outer side electromagnetic coil 26 (the annular protrusion 50 for the outer), the focusing member 90, the first pressing bar 92, the second pressing bar 94, and the outer peripheral portion. An induced current is generated in the third pressing bar 96. A strong magnetic field is formed in the vicinity of each of the outermost, third from outermost, and fifth outermost leg portions 16. As a result, an electromagnetic force F1 that pushes the focusing member 90 toward the inner circumference is generated according to Fleming's left-hand rule.

By this electromagnetic force F1, the focusing member 90 moves inward in the radial direction of the stator core 12b while being guided by the guide portion. Along with this, the first pressing bar 92, the second pressing bar 94, and the third pressing bar 96 supported by the focusing member 90 are integrally displaced in the same direction as the focusing member 90. That is, the first pressing bar 92, the second pressing bar 94, and the third pressing bar 96 move inward in the radial direction of the stator core 12b. As can be understood from this, the focusing member 90, the first pressing bar 92, the second pressing bar 94 and the third pressing bar 96 are movable members.

As a result, the outermost leg 16, the third leg 16 from the outermost, and the fifth leg 16 from the outermost are formed by the first pressing bar 92, the second pressing bar 94, and the third pressing bar 96, respectively. Pressed and each inner peripheral side wall is placed on the outer circumference of adjacent legs 16 (second outermost leg 16, fourth outermost leg 16, innermost leg 16) on each inner peripheral side. It bends toward the side wall and abuts at supersonic speed. At this time, the oxide film is scattered from the contact portion, and the exposed base metal diffuses the atoms to each other. At this time, the first step support portion 98a, the second step support portion 98b, and the third step support portion 98c of the block body 54b are the second leg portion 16 from the outermost side and the fourth step portion from the outermost side. The leg 16 and the innermost leg 16 support the inner peripheral wall side of the leg 16 on the inner peripheral side. That is, also in the fourth embodiment, the outer peripheral side leg portion 16 is brought closer by the first stepped support portion 98a, the second stepped support portion 98b, and the third stepped support portion 98c, and the inner peripheral side leg portion 16 is approached. Supports the inner peripheral side wall opposite to the outer peripheral side wall that abuts on. Therefore, the legs 16 on the inner peripheral side maintain their original positions before and after the contact.

Further, since an induced current is generated in the legs 16 bent by pressing, Joule heat and thermal energy are generated at the contact points between the legs 16. For the above reasons, the legs 16 are metallurgically joined to each other substantially at the same time as the contact. Similar to the first to third embodiments, the time required for bending, contacting and joining is 1 second or less, typically 0.5 seconds or less.

The above phenomenon proceeds simultaneously in all 18 sets of slot groups 22b. That is, according to the fourth embodiment, even when the number of slots 20 constituting one set of slot group 22b exceeds four, all the legs 16 located on the outer peripheral side and the inner peripheral side thereof. All of the adjacent legs 16 can be joined at the same time in one operation. Therefore, the time required to obtain the stator is remarkably shortened, so that the production efficiency of the stator can be improved.

Moreover, since the induced currents are generated substantially the same throughout, it is possible to avoid a large difference in quality for each joint. Therefore, no repair is required, and the joining work is simplified. That is, even when the number of slots 20 constituting one set of slot groups 22b exceeds four, the same effects as those of the first to third embodiments can be obtained.

The present invention is not particularly limited to the above-described first to fourth embodiments, and various modifications can be made without departing from the gist of the present invention.

For example, for the segment 10 inserted into the slot 20 of the stator core 12b shown in FIGS. 13 and 14, a joining device having a configuration similar to that of the joining device 14b (see FIG. 5) or the joining device 14c (see FIG. 9) is used. May be used for joining.

Further, the I-shaped segment may be used instead of the substantially U-shaped segment 10.

Further, in the fourth embodiment, it is not particularly necessary that the materials of the first pressing bar 92, the second pressing bar 94, and the third pressing bar 96 generate an induced current in the leg portion 16, and the displaced first. The legs may only be pressed by the pressing bar 92, the second pressing bar 94, and the third pressing bar 96.

10 ... Segments 12a, 12b ... Stator cores 14a to 14d ... Joining device 16 ... Legs 18 ... Turns 20 ... Slots 22a, 22b ... Slots 26 ... Outer side electromagnetic coil 28 ... Outer side magnetic flux concentrator 32 ... Stator stage 34 ... Outer coil step 48 ... Current supply 50 ... Outer annular protrusion 52 ... Support 54a, 54b ... Block 70 ... Inner side electromagnetic coil 72 ... Inner side magnetic flux concentrator 74 ... Inner annular protrusion 74 ... Inner annular protrusion 76 ... Inner side coil step 90 ... Focusing member 92 ... 1st pressing bar 94 ... 2nd pressing bar 96 ... 3rd pressing bar 98a ... 1st step supporting 98b ... 2nd step supporting 98c ... 3rd Stepped support

Claims (7)

Two legs of an electric conductor (10) inserted into a plurality of slots (20) provided in the circumferential direction of a ring-shaped stator core (12a) protruding from the stator core (12a) and adjacent to each other in the radial direction. It is a method of joining an electric conductor (10) that joins parts (16) to each other.
A step of arranging the electromagnetic coils (26, 70) in a circumferential shape on at least one of the inner peripheral side and the outer peripheral side of the stator core (12a).
By energizing the electromagnetic coils (26, 70), the two adjacent legs (16) are brought into contact with each other, and the two abutted legs (16) are joined to each other. ,
A method for joining an electric conductor (10), which comprises. In the joining method according to claim 1, an induced current is generated in one of the two adjacent legs (16), and one of the two legs (16) is made to be the other by the electromagnetic force generated by the induced current. A method of joining an electric conductor (10), which comprises bringing the legs (16) into contact with each other. In the joining method according to claim 1 or 2, an electric conductor (10) is characterized in that electromagnetic coils (26, 70) are arranged in a circumferential shape on both the inner peripheral side and the outer peripheral side of the stator core (12a). ) Joining method. In the joining method according to claim 1, one of the two adjacent legs (16) is brought closer to the other by the movement of the movable member (90, 92, 94, 96) in which an electromagnetic force is generated, and the leg portion. (16) A method for joining electric conductors (10), which comprises bringing them into contact with each other. Two legs of an electric conductor (10) inserted into a plurality of slots (20) provided in the circumferential direction of a ring-shaped stator core (12a) protruding from the stator core (12a) and adjacent to each other in the radial direction. It is a joining device (14a) of an electric conductor (10) that joins parts (16) to each other.
Electromagnetic coils (26, 70) arranged on the circumference of at least one of the inner peripheral side and the outer peripheral side of the stator core (12a), and
A current supply unit (48) that supplies a current to the electromagnetic coils (26, 70) and
Support for supporting the other leg (16) from the side opposite to the point where the one leg (16) abuts when one of the two legs (16) approaches the other. Member (54a) and
The joining device (14a) of the electric conductor (10), which comprises. The joining device (14d) according to claim 5 further includes movable members (90, 92, 94, 96) arranged between the electromagnetic coil (26, 70) and the electric conductor (10). The joining device (14d) of the electric conductor (10). The joining device (14a) according to claim 5 has an inner side electromagnetic coil (70) arranged on the inner peripheral side of the stator core (12a) and an outer side electromagnetic coil (26) arranged on the outer peripheral side. A joining device (14a) for an electric conductor (10).

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