JP2772329B2 - Welding structure of electrical connection by laser - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a welded structure of an electrical connection portion by a laser in which a thin coated single wire or the like is firmly welded to a terminal or a bus bar using a laser.

[0002]

2. Description of the Related Art FIG. 17 shows a conventional laser welding structure of an electrical connection portion. In this structure, a conductor (wire bundle) 82 of a covered electric wire 81 is placed on the surface of a conductive metal plate 80 such as a terminal or a bus bar, and the conductor 82 is irradiated with a laser 83 vertically from above. , The conductor portion 82
And the conductive metal plate 80 by welding. Further, as shown in FIG. 18, the thin polyurethane coating single line 8
When connecting 6, the coating 91 was directly irradiated with the laser 87 without peeling the coating 91, and was welded to the conductive metal plate 88.

However, in these conventional structures, the welded portions 84, 89 of the electric wires 81, 86 are greatly recessed (85, 90), and the strength of the electric wires 81, 86 in the pulling and peeling directions is significantly reduced. There was a problem that would.
Also, as shown in FIG. 18 , when the coating single wire 86 is directly welded, the vapor of the coating 91 melted by the laser 87 is mixed into the welding portion 89 to generate a large number of voids (bubbles) 92, which are again welded. This was a major cause of the decrease in strength.

[0004]

[0008] In view of the above facts, eliminating the occurrence of dents and void welds, electrical connections by laser capable of firmly welding the wire to the terminal and the bus bar or the like An object is to provide a welding structure.

[0005]

In order to achieve the above object, according to the first aspect of the present invention, a folded portion is provided facing a conductive metal plate, and an electric wire is provided between the conductive metal plate and the folded portion. In a welding structure of an electrical connection portion by a laser that irradiates a laser in a direction connecting the folded portion, the electric wire, and the conductive metal plate, and welds the folded portion, the electric wire, and the conductive metal plate. A rising portion is extended from the conductive metal plate, an inclined portion is extended from the rising portion toward the conductive metal plate, the folded portion is extended from the inclined portion, and the folded portion is extended by the inclined portion. Characterized in that a biasing force in the direction of clamping the electric wire is applied to the wire. A positioning piece for the electric wire may be formed upright on the conductive metal plate (claim 2). According to a third aspect of the present invention, a folded portion is provided so as to face the conductive metal plate, an electric wire is positioned between the conductive metal plate and the folded portion, and the folded portion, the electric wire, and the conductive metal plate are provided. In a welding structure of an electrical connection portion by a laser for irradiating a laser in a direction connecting the folded portion, the electric wire and the conductive metal plate, a rising portion is extended from the conductive metal plate, The folded portion is formed so as to be inclined in a tapered shape from a raised portion, and a tip end portion of the electric wire is inserted between the folded portion and the conductive metal plate so as to be nipped. According to a fourth aspect of the present invention, an electric wire is positioned between two opposing conductive metal plates, and a laser is irradiated in a direction connecting one conductive metal plate and the electric wire to the other conductive metal plate. In a welding structure of an electric connection portion by a laser for welding a metal plate and the electric wire, a locking claw is protruded from the one conductive metal plate and an insulating base having an engagement hole for the locking claw is provided. On the base, a mounting groove for the other conductive metal plate is provided, and the locking claw is engaged with the engagement hole,
The electric wire is sandwiched between both conductive metal plates. A positioning groove for the electric wire may be provided in the other conductive metal plate (claim 5). According to a sixth aspect of the present invention, a core element of an electric wire is positioned between two conductive metal plates, and a laser is irradiated from above one of the conductive metal plates toward the core element, and the two conductive metal plates are irradiated with a laser. In the welding structure of the electrical connection portion by a laser for welding the core element and the core element wire, the one conductive metal plate is bent into an inverted concave cross section to form a conductive metal cover, and the other conductive metal plate is placed on an insulating base. A plate is vertically implanted, and on both sides of the other conductive metal plate, the base is provided with engagement grooves for bent portions on both sides of the conductive metal cover, and the engagement between the conductive metal cover and the other conductive metal plate is provided. The core element wires are arranged separately in gaps having an inverted concave cross section therebetween. According to a seventh aspect of the present invention, an electric wire is positioned between two opposing conductive metal plates, and a laser is irradiated in a direction connecting one of the conductive metal plates and the electric wire to the other conductive metal plate. In a welding structure of an electrical connection portion by a laser for welding a metal plate and the electric wire, the one conductive metal plate is a metal chip, the other conductive metal plate is a bottom plate portion of a terminal, and a through hole for beam irradiation is provided. The metal chip is set on an insulating base board having a base plate, the bottom plate portion is set on an insulating terminal board having an accommodation recess for the base board, the base board is fitted into the accommodation recess, and the base The metal chip and the bottom plate portion are pressed by the board and the terminal board in the direction of clamping the electric wire.

[0006]

According to the structure of the first aspect, the wire clamping force is applied to the folded portion by the elasticity of the inclined portion. Thereby, the electric wire is strongly clamped between the folded portion and the conductive metal plate. No gap is formed between the electric wire, the folded portion, and the conductive metal plate, and the electric wire comes into surface contact with the folded portion and the conductive metal plate, and receives an appropriate pressing force. This improves the weldability. According to the structure of the second aspect, the electric wire is reliably positioned by the positioning piece, and the positional accuracy of the electric wire with respect to the laser is improved. Also,
According to the structure of the third aspect, by inserting the electric wire between the folded portion and the conductive metal plate, the distal end portion of the electric wire is tightly held between the folded portion and the conductive metal plate, and the weldability is improved as described above. improves. Further, according to the structure of the fourth aspect, the electric wire is strongly clamped between the two conductive metal plates by engaging the locking claw pieces with the engagement holes. Thereby, the weldability is improved. Further, according to the structure of the fifth aspect, the electric wire is reliably positioned by the positioning groove, and the positional accuracy of the electric wire with respect to the laser is improved. Further, according to the structure of claim 6, each element wire comes into contact with the conductive metal cover and the conductive metal plate to improve the electrical contact property, and the molten conductive metal cover flows through the gap from top to bottom. Thus, the individual wires are uniformly welded to each other, and the gap is filled with the molten metal. According to the structure of the seventh aspect, by fitting the base board to the terminal board, the electric wire is strongly sandwiched between the base board and the terminal board.
Thereby, the weldability is improved.

[0007]

FIG. 1 shows the basic concept of a welding structure of an electric connection portion by a laser according to the present invention. In this structure, a thin coated single wire 1 (having a diameter of 1 mm or less) is sandwiched between two conductive metal plates 2 and 3 such as terminals or bus bars, and the upper conductive metal plate 2 A laser 4 is irradiated vertically from above to weld and connect the coated single wire 1 and the two conductive metal plates 2 and 3 to each other. The conductive metal plates 2 and 3 are formed of a material having compatibility with the coated single wire 1, for example, phosphor bronze or beryllium copper.

According to this structure, as shown in FIG. 2, the upper conductive metal plate 2 melts in a largely concave state, and at the same time, the coated single wire 1 located in the middle and the lower conductive metal plate 3 are both heated. The coated single wire 1 is firmly welded to the upper and lower conductive metal plates 2 and 3 without being dented (reduced in diameter).

As shown in Table 1, the average value of n = 10 as shown in the measurement results of the welding strength in the tensile direction of the electric wire 1 shows that the tensile strength of the electric wire itself is 3.1 kgf, whereas the conventional connection strength is 3.1 kgf. The structure is as low as 1.2 kgf, and the structure of the present invention is 2.9 kgf.
It has been greatly improved to f. The variation σ is 0.17 Kgf in the conventional structure, whereas it is 0.07 Kgf or less in the structure of the present invention, which means that the strength is stable.

[Table 1] The measurement method is shown in FIGS. 3 is a tensile test of the electric wire 1 itself, FIG. 4 is a tensile test of a conventional product, and FIG.
Is a tensile test of the product of the present invention.

Further, even if a force acts in the direction in which the coated single wire 1 is peeled off as shown by the arrow A in FIG.
Since the coated single wire 1 is bent with the edge portion 5 as a fulcrum and the peeling force is received at the bent portion 6, there is also a feature that the force is not directly applied to the welded portion 7 and the peeling strength is improved.

FIG. 6 shows, as a first embodiment of a welding structure of an electric connection portion by a laser according to the present invention, a structure in which a coated single wire is welded and connected to a bus bar. In this structure, a protruding bent portion 9 is formed upright at an intermediate portion of the bus bar 8, and a rising piece 11 coupled to an upper wall (conductive metal plate) 10 of the bent portion 9 is folded to provide a spring property. Is formed, the coated single wire 13 is held between the holding piece 12 and the upper wall 10, and a laser 14 is irradiated from above the holding piece 12 toward the coated single wire 13. Thus, the holding piece 12, the coated single wire 13, and the upper wall 10 are welded to each other. The holding piece 12 continues via a biasing inclined portion 75 inclined from the rising piece 11 toward the upper wall 10.

Here, the tip 15 of the holding piece 12 is bent upward to form a tapered guide for the coated single wire 13, and the upper wall 10 is formed by cutting and raising a positioning piece 16 for the coated single wire 13. I have.

FIG. 7 shows a contact terminal for welding and connecting a covered electric wire as a second embodiment. Contact terminal 1
Reference numeral 8 denotes a single conductive metal plate that is stamped and bent to form a forwardly inclined electric member facing the substrate portion 19 via a rising portion 76 at the tip of the substrate portion (conductive metal plate) 19. A contact top plate (returned portion) 20 is coupled, and an electric wire crimping piece 21 is provided upright on the rear end of the substrate portion 19. The conductor portion (strand bundle) of the covered electric wire 22 is provided. 23, and the tip of the conductor portion 23 is connected to the top plate portion 20 and the substrate portion 19.
And irradiate a laser 24 from above the top plate section 20 toward the conductor section 23 so that the top plate section 20 is sandwiched.
And the conductor portion 23 and the substrate portion 19 are welded to each other.

FIG. 8 shows, as a third embodiment, a fixing structure for welding an electric wire to a conductive metal plate. This structure uses a base 26 made of synthetic resin, ceramic, or the like.
The lower conductive metal plate 28 is set in the mounting groove 27, and the coated single wire 29 is placed on the conductive metal plate 28, and the through hole ( Aperture) 30, 3
The upper conductive metal plate 32 having a pair of locking pawls 31, 31 with respect to 0 is clamped and fixed by engaging the locking pawls 31 with the through holes 30.

Here, on the extension line for irradiating the laser 33 from the center of the mounting groove 27 of the base 26, that is, from above,
A void portion 34 is provided, and the lower conductive metal plate 28
Is formed with a positioning groove 35 for the coated single wire 29. In addition, it is also possible to place another covering single wire 36 orthogonal to the covering single wire 29 and to weld them together. In that case, it is preferable to form the positioning groove 37 in the upper conductive metal plate 32.

FIGS. 9 to 11 show, as a fourth embodiment, a structure in which a covered electric wire is welded to a vertical bus bar. In this structure, a vertical bus bar (conductive metal plate) 40 is planted on an insulating resin base 39 such as an electric connection box.
The conductor portion (core element wire) 44 of the covered electric wire 43 is loosened and uniformly arranged between the exposed upper end surface 41 and both side surfaces 42 of the "0", and an inverted concave conductive metal cover (conductive metal plate) 45 is placed thereon. The cover 47 is press-fitted and irradiated with a laser 47 from above the upper wall 46 of the conductive metal cover 45 toward the conductor 44 of the covered electric wire 43, and the conductive metal cover 45, the electric wire conductor 44, and the vertical busbar 40 Are welded to each other.

Here, the conductive metal cover 45 melted by the laser 47 flows downward along the vertical bus bar 40, and each element in the inverted concave gap 77 between the conductive metal cover 45 and the vertical bus bar 40 is formed. The wires 44 are uniformly welded. The conductive metal cover 45 is positioned by fitting the bent portion 49 into an engagement groove 48 provided in the insulating resin base 39.

FIG. 12 shows a fifth embodiment in which a flexible printed circuit (FPC) is used as an electric wire for welding. This structure corresponds to the flexible insulating resin sheet 51.
FPC 53 in which a plurality of circuit conductors 52 are juxtaposed on the surface of
Between the bus bar 54 and the board portion 56 of the press contact terminal 55, and irradiate a laser 57 from above the board portion 56 to each of the circuit conductors 52.
And the bus bar 54 are welded and connected.

Although the circuit conductor 52 of the FPC 53 is extremely thin, it is heated and melted together with the substrate portion 56 of the press contact terminal 55 melted by the laser 57, and
And the bus bar 54 are firmly connected. Also, FP
Even if a peeling force acts on the C53, the FPC 53 bends at the edge 58 of the substrate portion 56 of the press contact terminal 55 and receives the peeling force, similarly to the coated electric wire or the coated solid wire of the above-described embodiment. Does not act directly on the surface, and high peel strength can be imparted.

FIG. 13 shows, as a sixth embodiment, a structure in which thin bus bars are overlapped and welded to each other. In this structure, the tip of the upper bus bar 61 is folded back to make it double, and
To weld the upper bus bar 61 between the folded portion 62 and the lower bus bar 64.

FIGS. 14 to 16 show, as a seventh embodiment, a welded connection structure between a coated single wire and a press contact terminal in a relay board for a flat circuit body. In FIG. 14, reference numeral 66 denotes a terminal board on which a press contact terminal 67 is implanted, 68 denotes a coated single wire that is disposed to face a bottom plate (conductive metal plate) 69 of the press contact terminal 67, and 70 denotes a coated single wire 68. 7 shows a base board in which a disk-shaped conductive metal chip (conductive metal plate) 71 facing the above is disposed on a through hole 72. At the bottom of the terminal board 66, a housing recess 78 into which the base board 70 is fitted is formed.

FIG. 15 shows an assembled state where these are joined together.
FIG. 16 is a sectional view taken along line BB of FIG. Note that FIG.
In addition, a connector for external connection (not shown) is provided at the terminal portion 68a of the coated single wire 68, and an external electric wire (not shown) is provided at the press contact terminal 67.

As shown in FIG.
The coated single wire 68 is sandwiched between the bottom plate portion 69 of the press-contact terminal 67 and the conductive metal chip 71, and the conductive metal chip 71 is irradiated with the laser 73 from the through hole 72 of the base board 70 toward the coated single wire 68. The conductive metal chip 71, the covered electric wire 68 and the bottom plate 69 of the press contact terminal 67 are welded and connected to each other.
The feature is that it can be made thinner.

[0024]

As described above, according to the first aspect of the present invention, since the positive wire holding force is applied to the folded portion by the elasticity of the inclined portion, the electric wire is formed between the conductive metal plate and the folded portion. By inserting the wire between them, the wire is strongly clamped and receives an appropriate pressing force. Thereby, the electric wire is firmly welded to the conductive metal plate and the folded portion. According to the second aspect of the present invention, since the electric wire is accurately positioned by the positioning piece, the position accuracy of the electric wire with respect to the laser is improved. Also,
According to the third aspect of the present invention, by inserting the wire tip between the folded portion and the conductive metal plate, the wire tip is easily tightly held between the folded portion and the conductive metal plate. Similarly, it is firmly welded. According to the fourth aspect of the present invention, the electric wire is strongly sandwiched between the two conductive metal plates by engaging the locking claw pieces with the engagement holes, and is firmly welded in the same manner as described above. According to the fifth aspect of the present invention,
The electric wire is reliably positioned by the positioning groove, and the positional accuracy of the electric wire with respect to the laser is improved. According to the invention as set forth in claim 6, each of the wires comes into contact with the conductive metal cover and the conductive metal plate, and the molten conductive metal cover flows from the top to the bottom in the gap so that the wires are uniformly formed. Since the welding is performed and the gap is filled, the welding strength is increased and the reliability of the electrical connection is improved. According to the invention of claim 7, since the electric wire is strongly clamped between the base board and the terminal board by fitting the base board to the terminal board, the weldability is improved.

[Brief description of the drawings]

FIG. 1 is a perspective view showing a basic concept of a welding structure of an electric connection portion by a laser according to the present invention.

FIG. 2 is a longitudinal sectional view showing a welded state.

FIG. 3 is an explanatory view showing a tensile strength test method of an electric wire.

FIG. 4 is an explanatory view showing a tensile strength test method for a conventional product.

FIG. 5 is an explanatory view showing a tensile strength test method of the invention product.

FIG. 6 is a perspective view showing a first embodiment of the present invention.

FIG. 7 is a perspective view showing a second embodiment of the present invention.

FIG. 8 is a perspective view showing a third embodiment of the present invention.

FIG. 9 is a perspective view showing a fourth embodiment of the present invention.

FIG. 10 is a perspective view showing the assembled state.

11 is a sectional view taken along the line AA of FIG. 10;

FIG. 12 is a cutaway perspective view of a main part showing a fifth embodiment of the present invention.

FIG. 13 is a cutaway perspective view of a main part showing a sixth embodiment of the present invention.

FIG. 14 is an exploded perspective view showing a seventh embodiment of the present invention.

FIG. 15 is a perspective view showing the assembled state.

FIG. 16 is a sectional view taken along the line BB of FIG. 15 showing the electric wire welding state.

FIG. 17 is a cutaway perspective view of a main part showing a conventional structure for welding a covered electric wire by a laser.

FIG. 18 is a longitudinal sectional view showing a welded state of a coated single wire.

[Explanation of symbols]

DESCRIPTION OF SYMBOLS 10 Top wall (conductive metal plate) 11,76 Rising part 12 Nipping piece (return part) 16 Positioning piece 19 Substrate part (conductive metal plate) 20 Top plate part (return part) 26,39 Base 28,32 Conductive metal Plate 30 Through-hole (engagement hole) 31 Engagement claw piece 40 Vertical bus bar (conductive metal plate) 45 Conductive metal cover (conductive metal plate) 48 Engagement groove 49 Bend 55,67 Press-contact terminal 66 Terminal board 69 Bottom plate ( Conductive metal plate) 70 Base board 71 Conductive metal chip (conductive metal plate) 75 Inclined portion 78 Housing recess

Continued on the front page (72) Inventor Tetsuro Saimoto 2464-48 Yazuzu, Kosai-shi, Shizuoka Prefecture Inside Yazaki Parts Co., Ltd. Atsuyoshi 1500 Onjuku 1500, Susono City, Shizuoka Prefecture Yazaki Sogyo Co., Ltd. In-house (56) References JP-A-60-210383 (JP, A) JP-A-4-306817 (JP, A) JP-A-4-135086 (JP, A) JP-A-4-89190 (JP, A) JP-A-57-153419 (JP, A)

Claims (7)

(57) [Claims] 1. A folded portion is provided facing a conductive metal plate, an electric wire is positioned between the conductive metal plate and the folded portion, and a laser is provided in a direction connecting the folded portion, the electric wire, and the conductive metal plate. Irradiating the folded portion, the electric wire, and the conductive metal plate by a laser in a welding structure of an electrical connection portion, extending a rising portion from the conductive metal plate, and extending the conductive metal An electrical connection by a laser, wherein an inclined portion is extended toward the plate, the folded portion is extended from the inclined portion, and the biasing force is applied to the folded portion in the direction of pinching the wire by the inclined portion. Welding structure of the part. 2. The conductive metal plate according to claim 1, wherein a positioning piece for said electric wire is raised.
A welding structure of an electrical connection portion by the laser described in the above. 3. A folded portion is provided opposite to the conductive metal plate, an electric wire is positioned between the conductive metal plate and the folded portion, and a direction in which the folded portion is connected to the electric wire and the conductive metal plate. In a welding structure of an electric connection portion by a laser for irradiating a laser and welding the folded portion, the electric wire, and the conductive metal plate, a rising portion is extended from the conductive metal plate, and the folded portion is extended from the rising portion. A welding structure for an electrical connection portion by a laser, wherein a portion is formed so as to be inclined in a tapered shape, and a tip portion of the electric wire is inserted between the folded portion and the conductive metal plate so as to be sandwiched. 4. An electric wire is positioned between two opposing conductive metal plates, and a laser is irradiated in a direction connecting one of the conductive metal plates, the electric wire and the other conductive metal plate, and the two conductive metal plates and the electric wire are irradiated. In the welding structure of the electrical connection portion by laser welding, a locking claw is protruded from the one conductive metal plate, and the other is provided on an insulating base having an engagement hole for the locking claw. A mounting groove for a conductive metal plate, wherein the electric wire is clamped between the conductive metal plates by engaging the locking claw pieces with the engaging holes; . 5. The structure according to claim 4, wherein a positioning groove for the electric wire is provided in the other conductive metal plate. 6. A core wire of an electric wire is positioned between two conductive metal plates, and a laser is irradiated from above one of the conductive metal plates toward the core wire, and both the conductive metal plates and the core wire are radiated. In the welding structure of the electrical connection portion by a laser for welding, the one conductive metal plate is bent into an inverted concave cross section to form a conductive metal cover, and the other conductive metal plate is vertically implanted on an insulating base. Installed on the base on both sides of the other conductive metal plate,
An engaging groove is provided for a bent portion on both sides of the conductive metal cover, and the core element wires are arranged so as to be separated in a gap having an inverted concave cross section between the conductive metal cover and the other conductive metal plate. Welding structure of electrical connection by laser. 7. An electric wire is positioned between two opposing conductive metal plates, and a laser is irradiated in a direction connecting one of the conductive metal plates, the electric wire and the other conductive metal plate, and the both conductive metal plates and the electric wire are irradiated. In one embodiment, the one conductive metal plate is a metal chip, the other conductive metal plate is a bottom plate of the terminal, and an insulating material having a through hole for beam irradiation. The metal chip is set on the base board, the bottom plate portion is set on an insulating terminal board having an accommodation recess for the base board, the base board is fitted into the accommodation recess, and the base board and the terminal board are fitted. Wherein the metal chip and the bottom plate are pressed in the direction of clamping the electric wire.