JP6973055B2 - Conductor joining method - Google Patents

Description

The present disclosure relates to a conductor joining method for joining a coil wound around a stator core and a power line connected to a terminal.

Conventionally, as a welding device for welding the ends of electric conductors inserted into a stator core, a jig including a jig for supporting the stator, a welding torch, and a clamp jig is known (for example, Patent Document 1). reference). The clamp jig of this welding device clamps four sets of ends of electric conductors paired with each other from both sides in the circumferential direction of the stator core, and the welding device is a clamp of the electric conductor sandwiched by the clamping jig. Weld the ends in sequence. As a result, the coil is wound around the stator core, and the end of the power line connected to the terminal is electrically joined to the end of the coil. Then, the terminal of the power line is generally fixed to a terminal block installed in the housing of the electric motor including the stator, and is connected to another electric device via the terminal block.

International Publication No. 2017/159865

However, even if the welding device as described above is used, when the coil and the power line are joined, the end of the power line may be welded in an inclined state with respect to the end of the coil. In such a case, when assembling the stator to the housing of the motor, the position of the terminal connected to the power line shifts from the terminal block to be fixed, and the fixing work of the terminal to the terminal block is easy. Can't be executed. Further, if the position of the terminal is forcibly corrected and the terminal is fixed to the terminal block, the strength of the welded portion between the end of the power line and the end of the coil is adversely affected due to deformation of the power line or the like. There is a risk.

Therefore, it is a main object of the present disclosure to join the end of the power line so as not to cause the position of the terminal of the power line to be displaced at the end of the coil wound around the stator core.

The conductor joining method of the present disclosure is a conductor joining method in which an end of a coil formed of an insulating coated conductor and wound around a stator core is joined to the end of a power line connected to a terminal. Therefore, the portion of the coil from which the insulating coating has not been peeled off and the power line are clamped so that the end of the coil from which the insulating coating has been peeled off and the end of the power line are adjacent to each other. , The end of the coil and the end of the power line are clamped and welded to each other.

In this method, before the end of the power line is welded to the end of the coil from which the insulating coating has been peeled off, the portion of the coil from which the insulating coating has not been peeled off and the power line are clamped. As a result, it is possible to prevent the end of the power line from being welded to the end of the coil in a state of being inclined with respect to the end of the coil with the end of the insulating coating of the coil as a fulcrum. As a result, it is possible to join the end of the power line to the end of the coil so as not to cause the positional deviation of the terminal due to the inclination of the power line with respect to the end of the coil.

Further, when clamping the portion of the coil where the insulating coating is not peeled off and the power line, the coil may be pulled toward the power line side. As a result, since the end of the power line can be joined to the end of the coil with reference to the positions of the power line and the terminal, it is possible to better suppress the occurrence of the positional deviation of the terminal.

Further, the clamping force when clamping the end portion of the coil and the end portion of the power line is a clamping force when clamping the portion of the coil where the insulating coating is not peeled off and the power line. May be set smaller than. As a result, when the end of the coil and the end of the power line are clamped, it is possible to prevent the power line from inclining with respect to the end of the coil with the end of the insulating coating of the coil as a fulcrum. It will be possible.

It is a schematic block diagram which shows the stator for a motor manufactured by using the conductor joining method of this disclosure. It is a top view which shows the stator for a motor of FIG. It is explanatory drawing which shows an example of the procedure of joining the end of a coil wound around a stator core, and the end of a power line connected to a terminal. It is an enlarged view of the main part for demonstrating the conductor joining method of this disclosure. (A) and (b) are schematic views for explaining the conductor joining method of this disclosure. It is an enlarged view of the main part for demonstrating the conductor joining method of this disclosure. It is explanatory drawing which shows the main part of the stator for a motor manufactured by using the conductor joining method of this disclosure.

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

FIG. 1 is a schematic configuration diagram showing a motor stator 1 manufactured by using the conductor joining method of the present disclosure, and FIG. 2 is a plan view showing a motor stator 1. The motor stator 1 shown in these drawings, together with a rotor (not shown), constitutes a three-phase AC motor used as a traveling drive source or a generator of, for example, an electric vehicle or a hybrid vehicle. The motor stator 1 of the present embodiment includes a stator core 2 and a plurality of stator coils 3.

The stator core 2 is formed by laminating a plurality of electromagnetic steel sheets 21 (see FIG. 2) formed in an annular shape by, for example, pressing, and exhibits an annular shape as a whole. The stator core 2 has a plurality of core slots (not shown) formed between a plurality of teeth portions (not shown) protruding inward in the radial direction at intervals from the outer peripheral portion of the annular shape and adjacent teeth portions, respectively (not shown). And include. The stator core 2 may be integrally formed, for example, by pressure-molding and sintering ferromagnetic powder.

The plurality of stator coils 3 include a U-phase coil, a V-phase coil, and a W-phase coil, and each stator coil 3 is formed by electrically joining a plurality of segment coils 4. The segment coil 4 is an electric conductor formed by bending a flat wire having an insulating film having an insulating film having a thickness of about 0.2 to 0.3 mm formed on the surface thereof into a substantially U shape. It has two tips from which the insulating coating has been removed. The two legs of each segment coil 4 are inserted into the corresponding core slots of the stator core 2, respectively, and the portion protruding from one end surface (upper end surface in FIG. 1) of the stator core 2 of each segment coil 4 is bent (not shown). Bending using a processing device is performed.

The tip of each segment coil 4 after bending extends in the axial direction of the stator core 2 and is electrically joined to the tip of another corresponding segment coil 4 by welding (TIG welding in this embodiment). NS. As a result, a plurality of stator coils 3 are wound around the stator core 2, and each stator coil 3 has two annular coil end portions 3a and 3b protruding outward from the end face of the stator core 2 in the axial direction. Further, an insulator (insulating paper) (not shown) is arranged in each core slot of the stator core 2.

Of the large number of segment coils 4 inserted into the core slots of the stator core 2, one end of the three segment coils 4u, 4v, 4w is not joined to the other segment coils 4, and is shown in FIGS. 1 and 2. As shown, it is bent toward the outer periphery of the stator core 2 by a bending device (not shown), and is bent upward in FIG. 1. Hereinafter, one end of the three segment coils 4u, 4v, 4w drawn out to the outer peripheral side of the stator core 2 in this way is referred to as a leader wire (first conductor) 40u, 40v, 40w. The leader wire 40u is included in the U-phase coil, the leader wire 40v is included in the V-phase coil, and the leader wire 40w is included in the W-phase coil.

The tip portion 41 (first tip portion: portion where the insulating coating is peeled off) of the leader wire 40u extends in the axial direction of the stator core 2 as shown in FIG. 1, and is a U-phase terminal as shown in FIG. By welding (in this embodiment, TIG welding) to the tip portion 51 (second tip portion: portion where the insulating coating is peeled off, see FIG. 3) of the power line (second conductor) 50u electrically joined to 5u. It is electrically joined. Further, the tip portion 41 of the leader wire 40v also extends in the axial direction of the stator core 2 and is welded to the tip portion 51 of the power line (second conductor) 50v electrically joined to the V-phase terminal 5v (this implementation). In the form, it is electrically joined by TIG welding). The tip 41 of the leader wire 40w also extends in the axial direction of the stator core 2 and is welded to the tip 51 of the power line (second conductor) 50w electrically joined to the W phase terminal 5w (in the present embodiment). , TIG welding) to be electrically joined. The power lines 50u, 50v, and 50w are formed of, for example, round wires (electrical conductors) having an insulating film formed on their surfaces, and are fixed to the resin holding member 6, respectively. The terminals 5u-5w are fixed to a terminal block (not shown) installed (fixed) in the housing of the motor (not shown) when the motor stator 1 is assembled to the housing.

Here, when joining the tip portion 41 of the leader line 40u-40w and the tip portion 51 of the power line 50u-50w, the tip portion 51 of the power line 50u-50w is attached to the tip portion 41 of the leader line 40u-40w. It may be welded in an inclined state. That is, as shown in FIG. 3, the tip portion 41 of the leader wire 40u-40w from which the insulating coating 45 has been peeled off and the tip portion 51 of the power line 50u-50w are clamped by a clamp 200 that functions as a welding electrode (cathode). When both are TIG welded, the tip portion 51 may be slightly inclined with respect to the tip portion 41 with the end portion 45e of the insulating coating 45 of the leader wire 40u-40w as a fulcrum.

In such a case, even if the inclination of the tip 51 with respect to the tip 41 is slight, as shown in FIG. 3, the terminal 5u-5w of the power line 50u-50w whose inclination is separated from the tip 51 The effect on the position and posture cannot be ignored. Therefore, when the tip portion 51 of the power line 50u-50w is welded to the tip portion 41 of the leader wire 40u-40w in an inclined state, the position of the terminal 5u-5w is displaced from the terminal block to be fixed. Therefore, the work of fixing the terminal 5u-5w to the terminal block cannot be easily performed. Further, when the position of the terminal 5u-5w is displaced, the position of the terminal 5u-5w is forcibly corrected and the terminal 5u-5w is fixed to the terminal block. There is a possibility that the strength of the welded portion between the portion 51 and the tip portion 41 of the leader wire 40u-40w may be adversely affected.

Based on this, when manufacturing the stator 1 for a motor, the tip portion 41 of the leader wire 40u-40w and the tip portion 51 of the power line 50u-50w are joined by a procedure as described below. As shown in FIG. 4, for example, when joining the tip portion 41 of the leader wire 40u and the tip portion 51 of the power line 50u, first, the portion where the insulating film of the leader wire 40u is not peeled off and the insulating film of the power line 50u are joined. The portion where is not peeled off is clamped by the clamp 100. As shown in FIGS. 5A and 5B, the clamp 100 includes a pressing member 101, a pulling member 102 having a claw portion 102a, and a driving device (not shown). The pressing member 101 and the pulling member 102 are made of a material (for example, iron) having a lower conductivity than the material (for example, copper) forming the clamp 200 that functions as a welding electrode.

The clamp 100 is in a state where the pressing member 101 is pressed against one of the leader line 40u (40v, 40w) and the power line 50u (50v, 50w) (see FIG. 5A), and the leader line 40u (see FIG. 40v, 40w) and the other of the power lines 50u (50v, 50w) are pulled to one side to clamp both (see FIG. 5B). Then, in the present embodiment, as shown in the figure, the leader wire 40u (40v, 40w) is attracted to the power line 50u (50v, 50w) side to clamp the portions where the insulating coatings of both are not peeled off.

Next, as shown in FIG. 6, the tip portion 41 of the leader wire 40u and the tip portion 51 of the power line 50u-50v are clamped by the clamp 200 functioning as a welding electrode. In the present embodiment, the clamping force of the clamp 200 that clamps the tip portions 41 and 51 is the clamping force of the clamp 100 that clamps the portions of the leader wire 40u and the power wire 50u where the insulating coating is not peeled off (for example, about 200N). ) Is smaller (for example, about 150N). Then, while the inert gas is blown from the welding torch 201 including the tungsten electrode (anode) (not shown) to the tip portions 41 and 51, both are melted and joined by the arc from the welding torch 201.

As a result, the tip 51 of the power line 50u-50v is inclined to the tip 41 with respect to the tip 41 of the leader 40u-40w with the end 45e of the insulating coating 45 of the leader 40u-40w as a fulcrum. It is possible to prevent welding from being welded. As a result, as shown in FIG. 7, the leader line 40u-40w is prevented from being displaced from the terminal 5u-5w due to the inclination of the power line 50u-50v with respect to the tip portion 41 of the leader line 40u-40w. It is possible to join the tip portion 51 of the power line 50u-50v to the tip portion 41 of the above.

Further, when the portion of the leader wire 40u-40w where the insulating coating 45 is not peeled off and the power line 50u-50v are clamped by the clamp 100, the leader wire 40u-40w is attracted to the power line 50u-50v side. The tip portions 41 and 51 can be joined with reference to the positions of the power line 50u-50v and the terminal 5u-5w. This makes it possible to better suppress the occurrence of the terminal 5u-5w positional deviation.

Further, in the above embodiment, the clamping force of the clamp 200 that clamps the tip portions 41 and 51 is set to be smaller than the clamping force of the clamp 100 that clamps the portions of the leader wire 40u and the power line 50u where the insulating coating is not peeled off. Be done. As a result, when the tip portions 41 and 51 are clamped by the clamp 200, the tip portion 51 of the power line 50u-50v is connected to the leader line 40u-40w with the end portion 45e of the insulating coating 45 of the leader line 40u-40w as a fulcrum. It is possible to suppress tilting with respect to the tip portion 41.

When the joining of the leader wire 40u-40w and the power line 50u-50v is completed, the stator core 2 has a coil end portion 3b in the lower part of the drawing from the coil end portion 3a side of each stator coil 3 exposed from the upper end surface in FIG. A resin such as varnish is applied toward the side. As a result, each segment coil 4 and an insulator (not shown) are fixed to the stator core 2 by the resin. Further, insulating powder is formed on exposed parts of the electric conductor such as the joint between the tips of the segment coil 4 and the joint between the tip 41 of the leader wire 40u-40w and the tip 51 of the power line 50u-50w. The body is applied.

As described above, according to the conductor joining method of the present disclosure, the occurrence of positional deviation of the terminal 5u-5w due to the inclination of the power line 50u-50v with respect to the tip portion 41 of the stator coil 3, that is, the leader wire 40u-40w. It is possible to join the tips 41 and 51 so as not to cause it. Although not shown, the clamps 100 and 200 may be configured to collectively clamp a plurality of sets of leader lines 40u-40w and power lines 50u-50v, or a plurality of sets of tip portions 41 and 51. good. Further, the tip portions 41 and 51 may be joined by welding other than TIG welding as long as they utilize a clamp that functions as a welding electrode.

It goes without saying that the invention of the present disclosure is not limited to the above-described embodiment, and various changes can be made within the scope of the extension of the present disclosure. Further, the above embodiment is merely a specific embodiment of the invention described in the column of the outline of the invention, and does not limit the elements of the invention described in the column of the outline of the invention.

The invention of the present disclosure can be used in the field of manufacturing electric motors and the like.

1 Motor stator, 2 stator core, 21 electrical steel sheet, 3 stator coil, 3a, 3b coil end, 4,4u, 4v, 4w segment coil, 40u, 40v, 40w leader wire, 41 tip, 45 insulation coating, 45e Termination part, 5u, 5v, 5w terminal, 50u, 50v, 50w power line, 51 tip part, 100 clamp, 101 holding member, 102 pulling member, 102a claw part, 200 clamp, 201 welding torch.

Claims (1)

Joins the end of a coil formed by an insulating coated conductor and wound around a stator core to the end of a power line formed by an insulating coated conductor and connected to a terminal. It is a conductor joining method,
The portion of the coil from which the insulating coating has not been peeled and the power line so that the end of the coil from which the insulating coating has been peeled off and the end of the power line from which the insulating coating has been peeled off are adjacent to each other. Clamp the part where the insulating coating is not peeled off,
Clamping when the end portion of the coil and the end portion of the power line are clamped between the portion of the coil where the insulating coating is not peeled off and the portion of the power line where the insulating coating is not peeled off. A conductor joining method in which clamps are clamped with a clamping force smaller than the force and the two are welded together.

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