JP7013344B2 - Welded part processing method for collective conductors and welded part processing equipment - Google Patents

Description

The present invention relates to a method for treating a welded portion of a collective lead wire for removing an insulating resin from a welded portion of the collective lead wire, and a welded portion processing device.

Collective conductors may be used as conductors for electrical equipment. The collective conductor is formed by bundling a plurality of conductors coated with an insulating resin. Collective conductors should have minimal insulation resin interposition between conductors, preferably at a thin non-conductor coating level, so as not to reduce the space factor of the conductors when mounted.

By the way, when the collective conductor is used as, for example, a segment coil of a motor stator (a coil in which a plurality of segment conductors are connected to each other), a load is applied from the outside in a state where the plurality of conductors are bundled to form a substantially V shape. It is necessary to bend and form (hairpin-like). At this time, if a plurality of conductors of the collective conductors are not fixed to each other, the conductors will be separated when a bending load is applied to the collective conductors, and handling will be difficult. Specifically, when a bending load is applied to the collective conductor in a state where the conductors are not firmly fixed to each other, the cross section of the entire collective conductor collapses in an attempt to displace each conductor at the shortest position, and further, when bending, bending is performed. The insulating resin located on the outermost side from the center is stretched, and the insulating resin is thinned. In order to deal with this concern, when the collective conductors are used for the segment coil of the motor stator or the like, the conductors of the collective conductors are fixed to each other by the insulating resin.

In the above-mentioned collective conductors, the bundled conductors are fixed by a relatively voluminous insulating resin. Therefore, for example, when the ends of different collective conductors are welded to each other, the conductors are preceded by welding. It is necessary to remove the insulating resin that covers the end of the.

As a method for treating a welded portion of this type of collective conductor, a method of removing the insulating resin at the end of the collective conductor with a stripping solution is known (see, for example, Patent Document 1).

Patent Document 1 describes that the ends of the collective conductors are kept in a constant posture and immersed in a peeling solution for a predetermined time, and the insulating resin of each conductor is removed by the peeling solution. When the insulating resin is removed from the end of the collective lead by this method, the end of the collective lead is washed with water and then dried.

Japanese Unexamined Patent Publication No. 2013-27071

However, in the method for treating the welded portion of the collective conductor described in Patent Document 1, it is necessary to remove the insulating resin of each conductor with a peeling solution, and then perform post-treatment such as washing with water or drying. Therefore, the work for removing the insulating resin from each conductor is complicated, and it takes a long time to complete the removal.

Further, in the case of the method for treating the welded portion of the collective conductor described in Patent Document 1, after the insulating resin at the end of the collective lead is removed by the stripping solution, a gap is formed between the adjacent conductors at the end. Therefore, after removing the insulating resin with the stripping solution, it is necessary to separately perform the work of filling the gap between the conductors. At this time, if the work of filling the gap between the conductors is not performed, there is a high possibility of causing a connection failure when welding the ends of different collective conductors.

Therefore, in the present invention, the insulating resin can be easily removed from the welded portion of the collective conductor in a short time, and the gap between the conductors from which the insulating resin has been removed can be filled. It is intended to provide a method and a welded portion processing device.

In order to solve the above-mentioned problems, the method for treating the welded portion of the collective conductor according to the present invention adopts the following configuration.
That is, in the method for treating a welded portion of a collective lead wire according to the present invention, a plurality of lead wires (for example, the lead wire 32 of the embodiment) coated with an insulating resin (for example, the insulating resins 31a and 31b of the embodiment) are bundled and assembled. The insulating resin is removed from the welded portion (eg, the welded portion 24a-1 of the embodiment) in which the lead wire (for example, the segment conductor 24 of the embodiment) is configured and welded to another member of the collective lead wire. A method for treating a welded portion of an aggregate lead wire, wherein the welded portion is heated to a temperature equal to or higher than the melting temperature of the insulating resin to melt the insulating resin, and after the first step, the above. The welded portion was pressed by a mold (for example, the upper mold 44U and the lower mold 44L of the embodiment) to plastically deform the metal of the welded portion and melted in the first step to obtain fluidity. The mold used in the second step has a second step of discharging the insulating resin from the welded portion, from one end side to the other end side in a direction substantially along the axial direction of the welded portion. It is characterized in that the opening cross section of the pressurizing portion is formed so as to gradually increase toward it .

In the welded portion treatment method according to the present invention, the insulating resin at the welded portion is melted by heating, and then pressure is applied by a mold to remove the insulating resin stagnant at the welded portion and to press-weld the conductors at the welded portion. conduct. Therefore, the insulating resin can be easily removed from the welded portion in a short time as compared with the case where the insulating resin at the welded portion is removed by using the peeling solution. Further, in this welded portion treatment method, the insulating resin stagnant in the welded portion is removed by pressurizing with a mold after heating, and the conductors of the welded portion are pressed against each other. The energization performance can be stabilized.
Further, in this case, when the mold is fastened, the insulating resin is easily discharged from one end side having a small opening area of the pressurized portion toward the other end side having a large opening area of the pressurized portion.

In the second step, it is desirable that the peripheral region of the cross section intersecting the axial direction of the collective conductor is pressurized by the mold.
In this case, in the second step, when the welded portion of the collective conductor is pressed by the mold, the peripheral region of the cross section intersecting the axial direction of the welded portion is pressed by the mold, so that the insulating resin existing in the welded portion is pressed. Is likely to be discharged to the outside along the axial direction of the welded portion. Therefore, when this configuration is adopted, the insulating resin is less likely to remain in the welded portion, and the energization performance at the connected portion is improved.

In at least one of the first step and the second step, vibration may be applied to the welded portion.
In this case, if vibration is applied to the molten insulating resin in the first step or the second step, the insulating resin is easily removed from the welded portion.

The welded portion processing apparatus for the collective conductor according to the present invention adopts the following configuration in order to solve the above problems.
That is, in the welded portion processing device for the collective lead wire according to the present invention, a plurality of lead wires (for example, the lead wire 32 of the embodiment) coated with the insulating resin (for example, the insulating resins 31a and 31b of the embodiment) are bundled and assembled. The insulating resin is removed from the welded portion (eg, the welded portion 24a-1 of the embodiment) in which the lead wire (for example, the segment conductor 24 of the embodiment) is configured and welded to another member of the collective lead wire. A heater (for example, heaters 41U, 41L of the embodiment) that heats and melts the insulating resin at the welded portion in a welded portion processing device for the collective lead wire, and the heater heats the insulating resin to a temperature higher than the melting temperature of the insulating resin. The welded portion is pressed by a mold (for example, the upper mold 44U and the lower mold 44L of the embodiment) to plastically deform the metal of the welded portion, and the insulating resin melted by heating the heater is used. A pressurizing device (for example, the pressurizing device 42 of the embodiment) for discharging from the welded portion is provided , and the mold is applied from one end side to the other end side in a direction substantially along the axial direction of the welded portion. It is characterized in that the opening cross section of the compression portion is formed so as to gradually increase .

With the above configuration, when removing the insulating resin from the welded part of the collective lead wire, the insulating resin of the welded part is melted by the heater, and then the pressure is applied by the pressurizing device to pressurize between the welded parts of the welded part. Discharge the insulating resin.
Further, in this case, when the mold is fastened, the insulating resin is easily discharged from one end side having a small opening area of the pressurized portion toward the other end side having a large opening area of the pressurized portion.

It is desirable that the mold pressurizes the peripheral region of the cross section that intersects the axial direction of the welded portion.
In this case, when the welded portion of the collective conductor is pressurized, the peripheral region of the cross section intersecting the axial direction of the welded portion is pressurized by the mold, so that the insulating resin existing in the welded portion is along the axial direction of the welded portion. And is smoothly discharged to the outside. Therefore, when this configuration is adopted, the insulating resin is less likely to remain in the welded portion, and the energization performance in the welded portion is improved.

The molds are a first mold (for example, the upper mold 44U or the lower mold 44L of the embodiment) and a second mold (for example, the lower mold 44L or the upper mold 44U of the embodiment) that pressurize the welded portion. ), And at least one of the first mold and the second mold has the welded portion in the direction intersecting the mold clamping direction in the cross section intersecting the axial direction of the welded portion at the time of molding. It may be configured to have a regulation wall for regulating displacement (for example, the regulation walls 44U-b, 44L-b of the embodiment).
In this case, when the first mold and the second mold are molded, the welded portion is pressurized in the mold clamping direction, and the displacement of the welded portion in the direction intersecting the mold clamping direction is regulated by the regulation wall. Weld. As a result, the insulating resin existing in the welded portion is easily discharged to the outside along the axial direction of the welded portion. In the case of this configuration, the structure of the mold can be simplified, so that the processing equipment can be made compact and the equipment cost can be reduced.

A vibration applying device (for example, the vibration generating device 47 of the embodiment and the ultrasonic transmitter 48) that applies vibration to the welded portion may be further provided.
In this case, when vibration is applied to the molten insulating resin from the vibration applying device, the insulating resin is easily removed from the welded portion.

According to the method for treating a welded portion of a collective lead wire of the present invention, the insulating resin at the welded portion is melted by heating, and then pressure is applied by a mold to press-weld the conductors at the welded portion and to insulate the welded portion. Since the resin is discharged, the insulating resin can be easily removed from the welded portion of the collective lead wire in a short time, and the gap between the lead wires from which the insulating resin has been removed can be filled.

Further, according to the welded portion processing device of the collective lead wire of the present invention, the insulating resin of the welded portion is melted by the heater, and then the pressure welding by the pressurizing device causes pressure welding between the lead wires of the welded portion and discharge of the insulating resin. It can be carried out. Therefore, according to the welded portion processing apparatus for the collective lead wire of the present invention, the insulating resin can be easily removed from the welded portion of the collective lead wire in a short time and easily, and the gap between the lead wires from which the insulating resin has been removed can be easily removed. Can be filled.

It is a schematic sectional drawing of the rotary electric machine of embodiment of this invention. It is a perspective view which shows a part of the stator of the rotary electric machine of embodiment of this invention. It is a perspective view which shows the end part of the segment conductor of 1st Embodiment of this invention. It is a perspective view which shows the state of the weld | weld part process of the segment conductor of 1st Embodiment of this invention. It is a schematic block diagram of the weld part processing apparatus of 1st Embodiment of this invention. It is a graph which shows the relationship between the heating temperature of a conducting wire, tensile strength, proof stress, and elongation. It is a vertical sectional view of the mold part of the welded part processing apparatus of 1st Embodiment of this invention. FIG. 3 is a cross-sectional view taken along the line VIII-VIII of FIG. 7B of the welded portion processing apparatus according to the first embodiment of the present invention. It is a vertical sectional view of the mold part of the welded part processing apparatus of the 2nd Embodiment of this invention. It is a vertical sectional view of the mold part of the welded part processing apparatus of the 3rd Embodiment of this invention.

Hereinafter, an embodiment of the present invention will be described with reference to the drawings.
FIG. 1 is a schematic cross-sectional view of a rotary electric machine 1 mounted on a vehicle.
The rotary electric machine 1 is a traveling motor mounted on a vehicle such as a hybrid vehicle, an electric vehicle, or a fuel cell vehicle. However, the rotary electric machine 1 is not limited to the above example, and can be applied to, for example, a motor for power generation mounted on a vehicle.

The rotary electric machine 1 includes a housing 3, an output shaft 9 rotatably supported by the housing 3, a rotor 7 attached to the output shaft 9 and rotating integrally with the output shaft 9 inside the housing 3, and a housing 3. It is installed inside and includes a stator 5 that generates a rotating magnetic field when energized. The rotor 7 includes a permanent magnet (not shown) and rotates by receiving a rotating magnetic field of the stator 5. Further, at the time of power generation, the generated power is output in the stator 5 by the rotation of the rotor 7 through the output shaft 9.
In the following description, with respect to the rotary electric machine 1, the direction along the axis C of the output shaft 9 is referred to as "axial direction".

FIG. 2 is a perspective view of the stator 5 removed from the housing 3 as viewed from one end side in the axial direction.
The stator 5 includes a stator core 11 and a coil 13 mounted on the stator core 11. The stator core 11 has a substantially cylindrical back yoke portion 19 attached to the inner peripheral portion of the housing 3, and a plurality of teeth portions 21 protruding radially inward from the inner peripheral surface of the back yoke portion 19. .. A plurality of teeth portions 21 are provided at equal intervals along the inner peripheral surface of the back yoke portion 19. Between the tooth portions 21 adjacent to each other in the circumferential direction, there is a slot 23 in which the coil 13 is mounted. The slot 23 penetrates the stator core 11 in the axial direction.

The coil 13 is a U-phase, V-phase, and W-phase three-phase coil. The coil 13 of each phase of the present embodiment is composed of a segment coil. The segment coil is formed by joining a plurality of segment conductors 24 by welding. Each segment conductor 24 has a substantially V-shaped bending connection portion 24c (see FIG. 4) that connects a pair of slot insertion portions 24b (see FIG. 4) inserted into different slots 23 and a pair of slot insertion portions 24b. And a connecting portion 24a projecting outward from each slot 23 on one end side in the axial direction of the stator core 11. The bent connection portion 24c is bent in a substantially V shape on the other end side of the stator core 11 in the axial direction. In the segment conductor 24 of each corresponding phase, the ends of the connecting portions 24a are connected to each other by TIG welding, laser welding, or the like on one end side in the axial direction of the stator core 11. In the stator 5 of the present embodiment, the coils 13 of each phase composed of the plurality of segment conductors 24 are mounted on the stator core 11 by distributed winding. Further, each segment conductor 24 is composed of square lines having a substantially rectangular cross section.

Further, the terminal portion of the coil 13 of each of the U-phase, V-phase, and W-phase (one end side in the axial direction of some segment conductors 24) is pulled out from one location on the radial outer side of the stator 5. In a terminal block (not shown), it is connected to an external electric circuit (not shown) such as a drive circuit. A metal terminal 30 for connecting to an external electric circuit is connected to the terminal portion of the coil 13 (segment conductor 24) of each phase. In the case of the present embodiment, the ends of the two segment conductors 24 located at the terminal portion of the coil 13 are overlapped and connected to the substantially cylindrical caulked portion 30a of one metal terminal 30.

The metal terminal 30 is abbreviated from the flat plate-shaped base portion 30b screwed to a terminal block (not shown), the caulking portion 30a connected to the segment conductor 24 of the terminal portion of the coil 13, and the end portion of the base portion 30b. It has a connecting portion 30c that is bent at a right angle to connect the base portion 30b and the caulking portion 30a.
The metal terminal 30 is made of, for example, a tin-plated copper alloy or the like.

<First Embodiment>
FIG. 3 is a perspective view showing an end portion of one segment conductor 24 welded to an adjacent segment conductor 24 on one end side in the axial direction of the stator core 11 (see FIG. 2). FIG. 4 is a perspective view showing how the end portion of one segment conductor 24 is pretreated by the welded portion processing device 40.
The end portion of the segment conductor 24 is subjected to pre-welding treatment such as removal of the insulating resins 31a and 31b by the welding portion processing device 40 described later. In the following, the portion of the connection portion 24a of the segment conductor 24 (collective conductor) to be welded is referred to as a welded portion 24a-1.

FIG. 7 is a cross-sectional view showing a schematic configuration of a main part of the welded portion processing device 40.
FIG. 7A shows the initial state of the start of the pretreatment by the welded portion processing device 40, and FIG. 7B shows the later state of the pretreatment by the welded portion processing device 40. In FIGS. 7 (A) and 7 (B), the welded portion 24a-1 of the segment conductor 24 is shown as a cross section.
As shown in the cross section of FIG. 7A, the segment conductor 24 is composed of a collective lead wire in which a plurality of lead wires 32 coated with the insulating resin 31a are bundled. In the present embodiment, the outer periphery of each conductor 32 is coated with a thermoplastic insulating resin 31a, and the insulating resin 31a on the outer periphery is melted and fused to each other in a state where a predetermined number of conductors 32 are bundled. There is. The outer peripheral portion of a predetermined number of conductors 32 fused to each other is covered with yet another insulating resin 31b. The insulating resin 31b is made of a thermoplastic resin. The insulating resin 31a covering each of the conductors 32 mainly prevents the conductors 32 from being separated from each other when the conductors 32 are fixed to each other and the segment conductor 24 is bent or the like.

The segment conductor 24 of the present embodiment is formed by pressing a predetermined number of conductors 32 covered with insulating resins 31a and 31b into a substantially rectangular cross-sectional shape. The segment conductor 24 is configured as a square wire by forming the collective conductor wire into a substantially rectangular cross-sectional shape. Therefore, the coil 13 to which the segment conductor 24 is connected is configured as a square wire coil.

In general, a square wire coil has the advantage of having a high space factor when wound around a core, but on the other hand, it causes problems such as an increase in the skin effect of the coil caused by a large cross-sectional area and an increase in eddy current loss. The square wire coil (coil 13) used in the present embodiment can alleviate the above-mentioned inconvenience by adopting a collective lead wire.

Insulating resins 31a and 31b are removed from the welded portion 24a-1 at the end of each segment conductor 24 by the welded portion processing device 40, and the adjacent conducting wires 32 are crimped to each other in that state. The pretreatment for the welded portion 24a-1 of the segment conductor 24 can be performed, for example, after the entire segment conductor 24 is bent and molded into a predetermined shape as shown in FIG.

FIG. 5 is a diagram showing an overall schematic configuration of the welded portion processing device 40.
The welded portion processing device 40 includes a pair of heaters 41U and 41L that heat and melt the welded portion 24a-1 of the segment conductor 24, and a pressurizing device 42 that pressurizes the welded portion 24a-1. The pressurizing device 42 raises and lowers the lower mold 44L fixed to the installation base 43, the upper mold 44U held by the movable base 45 and moves up and down together with the movable base 45, and the upper mold 44U, and pressurizes the upper mold 44U. The pressure actuator 46 is provided. In the present embodiment, one of the upper mold 44U and the lower mold 44L constitutes the first mold, and the other constitutes the second mold.

Guide stays 39 are projected from the four corners of the installation base 43 of the welded portion processing device 40, and a support table 38 for supporting the pressure actuator 46 is attached to the upper end of the guide stay 39. The movable base 45 is guided up and down by the guide stay 39. The pressurizing actuator 46 is composed of, for example, a hydraulic cylinder or the like. The rod portion 46a that moves the pressure actuator 46 forward and backward is connected to the movable base 45.

A vibration generating device 47 is interposed between the movable base 45 and the upper die 44U. The vibration generating device 47 is connected to the ultrasonic transmitter 48. The vibration generating device 47 receives the ultrasonic waves emitted by the ultrasonic transmitter 48 and causes the upper die 44U to vibrate minutely. In the present embodiment, the ultrasonic transmitter 48 and the vibration generating device 47 constitute a vibration applying device.
Further, the heaters 41U and 41L for heating the welded portion 24a-1 are installed inside each of the upper die 44U and the lower die 44L.

The heaters 41U and 41L, the pressurizing actuator 46, the ultrasonic transmitter 48 and the like are controlled by the control unit 49.
The upper die 44U and the lower die 44L are provided with temperature sensors 50U and 50L for detecting the temperature in the vicinity of the contact portion with the welded portion 24a-1. Further, some guide stays 39 are provided with a position sensor 51 for detecting the elevating height of the upper die 44U through the movable base 45. Further, a load sensor 52 for detecting a pressing load on the upper die 44U is installed on the rod portion 46a of the pressurizing actuator 46. These temperature sensors 50U and 50L, the position sensor 51, and the load sensor 52 are connected to the input side of the control unit 49. The control unit 49 controls the heaters 41U and 41L and the pressurizing actuator 46 in response to the detection signals of these sensors.

As shown in FIG. 7, the lower mold 44L has a lower pressure wall 44L-a that presses a pressure target (heating target) from below and one side of the lower pressure wall 44L-a (in the axial direction of the segment conductor 24). It has a regulation wall 44L-b protruding upward from one side in the horizontal direction on the surface intersecting with the above. The upper surface of the lower pressure wall 44L-a is flat and is inclined upward toward the other side (the other side in the horizontal direction in the plane intersecting the axial direction of the segment conductor 24). Further, the surface of the regulation wall 44L-b on the side facing the upper surface of the lower pressure wall 44L-a is inclined so as to form a substantially right angle with the upper surface of the lower pressure wall 44L-a.

Further, the upper die 44U is on a surface intersecting the upper pressurizing wall 44U-a that presses the pressurizing target (heating target) from above and the other side of the upper pressurizing wall 44U-a (the axial direction of the segment conductor 24). It has a regulation wall 44U-b protruding downward from the other side in the horizontal direction). The lower surface of the upper pressure wall 44U-a is flat and is inclined downward toward one side (one side in the horizontal direction in the plane intersecting the axial direction of the segment conductor 24). Further, the surface of the regulation wall 44U-b on the side facing the lower surface of the upper pressure wall 44U-a is inclined so as to form a substantially right angle with the lower surface of the upper pressure wall 44U-a.

The upper pressurizing wall 44U-a of the upper die 44U and the lower pressurizing wall 44L-a of the lower die 44L are formed so as to be parallel to each other. Similarly, the regulation wall 44U-b of the upper die 44U and the regulation wall 44L-b of the lower die 44L are formed so as to be parallel to each other. As shown in FIG. 7A, the welded portion 24a-1 having a rectangular cross section is placed on the lower mold 44L in an inclined state.

When the upper die 44U and the lower die 44L are molded (when the upper die 44U descends) with the welded portion 24a-1 placed on the lower die 44L, the upper pressurizing wall 44U- of the upper die 44U The lower surface of a abuts on the upper surface of the welded portion 24a-1. At this time, when the upper die 44U and the lower die 44L are heated to a predetermined temperature by the heaters 41U and 41L, the heat of the heaters 41U and 41L is transferred to the insulating resins 31a and 31b of the welded portion 24a-1 and the conducting wire 32. Will be done. At this time, when the welded portions 24a-1 are heated to a temperature higher than the melting temperature of the insulating resins 31a and 31b by the heat of the heaters 41U and 41L, the insulating resins 31a and 31b are melted.

Further, when the mold clamping is further advanced from the above state, the welded portion 24a-1 is pressurized from above and below by the upper pressurizing wall 44U-a and the lower pressurizing wall 44L-a, and the welded portion 24a-1 is pressed up and down. Displace to be crushed. At this time, the welded portion 24a-1 tries to be displaced to the outside in the width direction (left-right direction), but the displacement of the welded portion 24a-1 to the outside in the width direction is regulated by the regulation walls 44L-b and 44U-b. Will be done. As a result, a uniform pressure is applied to the welded portion 24a-1 from the peripheral region, and the insulating resins 31a and 31b adhering to the welded portion 24a-1 and stagnating are welded under the uniform pressure. It is extruded to the outside of the site 24a-1.

Here, the heating temperature of the heaters 41U and 41L with respect to the welded portion 24a-1 exceeds the melting point of the material of the insulating resins 31a and 31b in order to avoid carbonization of the insulating resins 31a and 31b at the welded portion 24a-1. Moreover, it is desirable to control the temperature to slightly exceed the thermal decomposition start temperature of the material. Specifically, for example, when the insulating resins 31a and 31b are PAI resins (polyamide-imide resin), the lower limit temperature is set to a temperature exceeding 300 ° C., and when the insulating resins 31a and 31b are PI resins (polyimide resin), the lower limit temperature is set. The temperature is set to exceed 490 ° C. The upper limit temperature (upper limit temperature detected by the temperature sensors 50U, 50L) is when the separation distance between the temperature sensors 50U, 50L for detecting the temperature in the vicinity of the heaters 41U, 41L and the inside of the welded portion 24a-1 is large. The temperature is set to be the temperature obtained by adding about 50 ° C. to the thermal decomposition start temperature of each resin material.

Further, it is desirable that the pressurized surfaces of the upper die 44U and the lower die 44L have smooth surfaces in order to prevent the welded portions 24a-1 from sticking at the time of mold release. Further, a coating agent having excellent peelability may be applied to the pressurized surfaces of the upper die 44U and the lower die 44L.

FIG. 8 is a view showing a cross section of the welded portion processing device 40 along the line VIII-VIII of FIG. 7 (B).
As shown in FIG. 8, the cross section of the pressurizing portion of the upper die 44U and the lower die 44L (the portion surrounded by the upper pressurizing wall 44U-a, the lower pressurizing wall 44L-a, the regulation wall 44U-b, 44L-b). In the cross section), the opening area gradually increases from one end side to the other end side in a direction substantially along the axial direction of the welded portion 24a-1. Therefore, in a state where the insulating resins 31a and 31b are melted, when the welded portion 24a-1 is pressed by the upper die 44U and the lower die 44L with a force equal to or higher than a predetermined pressure, the insulating resins 31a and 31b are molded (upper). It flows in the mold 44U and the lower mold 44L) from one end side having a small opening area toward the other end side having a large opening area. Therefore, by setting the welded portion 24a-1 in the mold so that the terminal portion of the welded portion 24a-1 is directed toward the other end side (the side having a large opening area) in the mold, the insulating resins 31a and 31b can be obtained. It can be smoothly discharged to the terminal portion side of the welded portion 24a-1.

FIG. 6 is a graph showing the temperature when oxygen-free copper is heated and the changes in each characteristic of elongation, tensile strength, and proof stress.
As shown in FIG. 6, oxygen-free copper has improved elongation characteristics of 10% or more when heated to 250 ° C. or higher, and tensile strength and proof stress are half or less, as compared with the case of normal temperature of 100 ° C. or lower. Will be. Therefore, when the conductor 32 of the segment conductor 24 is formed of oxygen-free copper, the heating temperature of the welded portion 24a-1 by the heaters 41U and 41L is set to 250 ° C. or higher, preferably 300 ° C. or higher for welding. The metal (conductor 32) in the portion 24a-1 can be easily plastically deformed.

Next, a specific pretreatment by the welded portion processing device 40 will be described.
At the start of processing, the welded portion processing device 40 preheats the upper die 44U and the lower die 44L to predetermined temperatures by the heaters 41U and 41L. From this state, the upper die 44U is lowered with respect to the work to be processed (welded portion 24a-1 of the segment conductor 24) placed on the lower die 44L.

When the upper die 44U descends to a predetermined height and comes into contact with the work, the upper die 44U and the lower die 44L are heated to a predetermined temperature by the heaters 41U and 41L. The predetermined temperature at this time is a temperature equal to or higher than the melting temperature of the insulating resins 31a and 31b of the welded portion 24a-1. At this time, a relatively low pressure is applied to the upper die 44U from the pressurizing actuator 46, and each surface of the upper die 44U and the lower die 44L is pressed against the welded portion 24a-1. In this state, the elapse of a predetermined time is waited, and the heat of the heaters 41U and 41L is transferred to the insulating resins 31a and 31b of the welded portion 24a-1 and the conducting wire 32 inside the same (first step). Further, at this time, ultrasonic vibration may be applied to the upper die 44U from the vibration generating device 47. At this time, depending on the pressing force applied to the upper mold 44U, the insulating resins 31a and 31b heated to a temperature equal to or higher than the melting temperature may be discharged in a small amount from the welded portion 24a-1.

After that, while the heating of the upper die 44U and the lower die 44L is continued by the heaters 41U and 41L, the pressing force of the upper die 44U and the lower die 44L is increased to a predetermined pressure by the pressurizing actuator 46. At this time, ultrasonic vibration may be applied to the upper die 44U from the vibration generating device 47.
As a result, the peripheral region of the welded portion 24a-1 is pressed by the upper die 44U and the lower die 44L at a predetermined pressure, and the metal (lead wire 32) of the welded portion 24a-1 is mutually as shown in FIG. 7 (B). It is plastically deformed so as to be in close contact with. At this time, the molten insulating resins 31a and 31b are discharged to the outside from the welded portion 24a-1 (second step). This completes the pretreatment of the welded portion 24a-1 by the welded portion processing device 40.

If the insulating resins 31a and 31b remain in a part of the welded portion 24a-1 when the pretreatment by the welded portion processing device 40 is completed, the remaining insulating resins 31a and 31b are peeled off. It is also conceivable to peel it off with a solvent. When the collective conductor is immersed in a peeling solvent, there is a possibility that the insulating resin at an unnecessary part may be peeled due to the capillary phenomenon due to the gap between the plurality of conductors. However, when the welded portion 24a-1 is pretreated by the welded portion processing device 40 of the present embodiment, the metal (lead wire 32) of the welded portion 24a-1 is compacted, so that the peeling solvent is released due to the capillary phenomenon. There is no problem of adhering to the insulating resins 31a and 31b at unnecessary parts.

As described above, according to the treatment method executed by the welded portion processing device 40 of the present embodiment, welding is performed as compared with the case where the insulating resins 31a and 31b of the welded portion 24a-1 are removed by using a peeling solution. The insulating resins 31a and 31b can be easily removed from the portions 24a-1 in a short time. Further, in the treatment method executed by the welded portion processing apparatus 40 of the present embodiment, the insulation staying in the welded portion 24a-1 is applied by the pressurization by the molds (upper mold 44U and lower mold 44L) after heating. Since the conductors 32 of the welded portion 24a-1 are pressed against each other together with the removal of the resins 31a and 31b, the energization performance of the welded portion 24a-1 can be stabilized in a series of processes. Therefore, TIG welding can be satisfactorily performed on the welded portion 24a-1 that has been pretreated. Further, when laser welding is performed on the welded portion 24a-1 that has been pretreated, the metal (conductor 32) of the welded portion 24a-1 is integrally solidified at the pretreatment stage, so that welding heat is transferred. Is smooth, and the entire end can be welded stably.

Further, the welded portion processing device 40 of the present embodiment includes an upper die 44U and a lower die 44L that pressurize the peripheral region of the cross section intersecting the axial direction of the welded portion 24a-1. Therefore, when the welded portion 24a-1 of the segment conductor 24 is pressurized, the peripheral region of the cross section intersecting the axial direction of the welded portion 24a-1 is pressurized by the upper die 44U and the lower die 44L, so that welding is performed. The insulating resins 31a and 31b stagnant at the portions 24a-1 can be smoothly discharged to the outside along the axial direction. Therefore, when the welded portion processing device 40 of the present embodiment is adopted, the insulating resins 31a and 31b are less likely to remain in the welded portion 24a-1, and the energization performance and heat transfer in the welded portion 24a-1 are improved. ..

In particular, in the welded portion processing device 40 of the present embodiment, there is a regulation that regulates the displacement of the welded portion 24a-1 in the direction intersecting the mold clamping direction in the cross section intersecting the axial direction of the welded portion 24a-1 at the time of mold clamping. The walls 44U-b and 44L-b are provided on the upper die 44U and the lower die 44L. Therefore, with a simple configuration, the gap between the conductors 32 of the welded portion 24a-1 can be efficiently eliminated, and the insulating resins 31a and 31b remaining in the welded portion 24a-1 can be reliably discharged to the outside. Therefore, when this configuration is adopted, the structure of the mold can be simplified, so that the processing equipment can be made compact and the equipment cost can be reduced.

Further, in the welded portion processing device 40 of the present embodiment, the opening area of the pressurized portion of the upper die 44U and the lower die 44L is from one end side to the other end side in a direction substantially along the axial direction of the welded portion 24a-1. It is set to gradually increase toward. Therefore, the insulating resins 31a and 31b can be smoothly discharged in a certain direction when the upper die 44U and the lower die 44L are molded.

Further, the welded portion processing device 40 of the present embodiment includes a vibration generating device 47 that applies vibration to the welded portion 24a-1 at the time of heating or pressurization. Therefore, by applying vibration from the vibration generating device 47 to the molten insulating resin during the pretreatment by the welded portion processing device 40, the insulating resins 31a and 31b can be efficiently removed from the welded portion 24a-1.

Further, the welded portion processing device 40 of the present embodiment includes the upper pressurizing wall 44U-a on the upper die 44U side, each pressurizing surface of the regulation wall 44U-b, and the lower pressurizing wall 44L-a on the lower die 44L side. Since each pressure surface of the regulation wall 44L-b is formed so as to be inclined with respect to the elevating direction of the upper die 44U, it is said that the mold releasability with respect to the work (welded portion 24a-1 of the segment conductor 24) is good. There are advantages.

<Second Embodiment>
FIG. 9 is a cross-sectional view showing a schematic configuration of a main part of the welded portion processing device 40 of the second embodiment. FIG. 9A shows the initial state of the start of the pretreatment by the welded portion processing device 40, and FIG. 9B shows the later state of the pretreatment by the welded portion processing device 40. In each of the embodiments described below, the same parts as those in the first embodiment are designated by a common reference numeral, and duplicate description will be omitted.

In the welded portion processing device 40 of the present embodiment, the pressure surface of the lower pressure wall 44L-a on the lower mold 44L side and the pressure surface of the upper pressure wall 44U-a on the upper mold 44U side are formed substantially horizontally. There is. Further, the pressure planes of the regulation wall 44L-b on the lower die 44L side and the regulation wall 44U-b on the upper die 44U side are relative to the pressurizing surfaces of the lower pressurizing wall 44L-a and the upper pressurizing wall 44U-a. , Formed at approximately right angles.

In the welded portion processing device 40 of the present embodiment, the welded portions 24a-1 of the two segment conductors 24 are vertically overlapped and arranged between the upper die 44U and the lower die 44L. In this state, the welded portion processing device 40 heats the first step and pressurizes the second step, so that the insulating resins 31a and 31b are applied to the welded portions 24a-1 of the two segment conductors 24. Since the welded portion processing device 40 of the present embodiment, which removes and crimps the conductors 32 to each other at the same time, has the same basic configuration as that of the first embodiment, obtains the same basic effects as those of the first embodiment. be able to.

<Third Embodiment>
FIG. 10 is a cross-sectional view showing a schematic configuration of a main part of the welded portion processing device 40 of the third embodiment. FIG. 10A shows the initial state of the start of the pretreatment by the welded portion processing device 40, and FIG. 10B shows the later state of the pretreatment by the welded portion processing device 40.
The welded portion processing device 40 of the present embodiment differs from that of the first embodiment only in the shapes of the lower die 44L and the upper die 44U. That is, the lower mold 44L has a lower pressure wall 44L-a in the center of the upper surface, and regulation walls 44L-b are projected on both left and right sides of the lower pressure wall 44L-a. On the other hand, the upper die 44U does not have a regulation wall and has an upper pressurizing wall 44U-a projecting downward. The upper pressure wall 44U-a is fitted between the pair of regulation walls 44L-b of the lower mold 44L, and is welded together with the lower pressure wall 44L-a on the lower mold 44L side and the pair of regulation walls 44L-b. It is configured to pressurize 24a-1.

Also in the case of the welded portion processing device 40 of the present embodiment, although the shape of the mold is different, the welded portions 24a-1 can be pressurized to discharge the insulating resins 31a and 31b and crimp the conducting wires 32 to each other in the same manner. ..

The present invention is not limited to the above embodiment, and various design changes can be made without departing from the gist thereof. For example, in each of the above embodiments, the treatment is performed by the welded portion processing device as it is without removing the outer insulating resin 31b from the welded portion 24a-1 of the segment conductor 24, but the treatment by the welded portion processing device is performed. Before this is done, the insulating resin 31b on the outside of the welded portion 24a-1 may be removed by another jig.

24 ... Segment conductor (aggregate conductor)
24a-1 ... Welded parts 31a, 31b ... Insulating resin 32 ... Conductor 40 ... Welded part processing device 41 ... Heaters 41U, 41L
42 ... Pressurizing device 44U ... Upper mold (mold, first mold, or second mold)
44L ... Lower mold (mold, second mold, or first mold)
44U-b, 44L-b ... Regulatory wall 47 ... Vibration generating device (vibration imparting device)
48 ... Ultrasonic transmitter (vibration imparting device)

Claims (7)

A method for treating a welded portion of a collective conductor that removes the insulating resin from a welded portion where a plurality of conductors coated with an insulating resin are bundled to form a collective conductor and is welded to another member of the collective conductor. There,
The first step of heating the welded portion to a temperature equal to or higher than the melting temperature of the insulating resin to melt the insulating resin,
After the first step, the welded portion is pressed by a mold to plastically deform the metal of the welded portion, and the insulating resin melted in the first step to obtain fluidity is obtained from the welded portion. With a second step of discharging ,
The mold used in the second step is characterized in that the opening cross section of the pressure portion is gradually increased from one end side to the other end side in a direction substantially along the axial direction of the welded portion. Welded part processing method of the collective lead wire. The welded portion processing method for a collective lead wire according to claim 1, wherein in the second step, the peripheral region of the cross section intersecting the axial direction of the collective lead wire is pressed by the mold. The method for treating a welded portion of an aggregated conductor according to claim 1 or 2, wherein in at least one of the first step and the second step, vibration is applied to the welded portion. A welded portion processing device for a collective conductor that removes the insulating resin from a welded portion where a plurality of conductors coated with an insulating resin are bundled to form a collective conductor and is welded to another member of the collective conductor. There,
A heater that heats and melts the insulating resin at the welded portion,
The welded portion heated to a temperature equal to or higher than the melting temperature of the insulating resin by the heater is pressed by a mold to plastically deform the metal of the welded portion, and the insulating resin melted by the heating of the heater is discharged from the welded portion. With a pressurizing device ,
The mold is formed so that the opening cross section of the pressure portion gradually increases from one end side to the other end side in a direction substantially along the axial direction of the welded portion. Processing equipment. The welded portion processing device for a collective conductor according to claim 4, wherein the mold pressurizes a peripheral region of a cross section intersecting the axial direction of the welded portion. The mold comprises a first mold and a second mold that pressurize the weld site.
At least one of the first mold and the second mold regulates the displacement of the welded portion in the direction intersecting the mold clamping direction in the cross section intersecting the axial direction of the welded portion at the time of molding. The welded portion processing apparatus for a collective lead wire according to claim 5, which has a regulating wall. The welded portion processing device for a collective conductor according to any one of claims 4 to 6 , further comprising a vibration applying device for applying vibration to the welded portion.

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