JP2004220933A - Ultrasonic welding device and ultrasonic welding method for electric wire - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an ultrasonic welding device capable of improving welding strength and tensile strength of a welding part. <P>SOLUTION: The ultrasonic welding device for electric wires forms a welding part by laying a plurality of electric wires between a horn chip part 4 of an ultrasonic horn and an anvil 3 and fusing them by applying compression force and ultrasonic vibration. A welding strength maintaining face 6 on which an indentation 10 is formed, a tensile force maintaining face 7 arranged adjacent to the welding strength maintaining face 6 moving back from the welding strength maintaining face 6 toward an opposite side of the wire compressing direction, and an electric wire diameter restoring face 8 gradually moving back from the tensile force maintaining face 7 toward the opposite side of the wire compressing direction are formed on respective electric wire compressing faces 4a, 3a of both the horn chip part 4 and the anvil 3. <P>COPYRIGHT: (C)2004,JPO&NCIPI

Description

[0001]
TECHNICAL FIELD OF THE INVENTION
TECHNICAL FIELD The present invention relates to an ultrasonic welding apparatus and an ultrasonic welding method for an electric wire for connecting a plurality of electric wires by ultrasonic welding.
[0002]
[Prior art]
A technique for electrically connecting conductive members by ultrasonic welding has been proposed, for example, as disclosed in Japanese Patent Application Laid-Open No. 2002-217229 (Patent Document 1). The welding target of the ultrasonic welding disclosed in Japanese Patent Application Laid-Open No. 2002-217229 (Patent Document 1) is a wire and a semiconductor chip, but the ultrasonic welding is also used to electrically connect a plurality of electric wires. I have. Such a conventional ultrasonic welding apparatus will be described with reference to FIGS.
[0003]
As shown in FIG. 10, the ultrasonic welding apparatus 100 includes an ultrasonic horn 101 and an anvil 102, and a horn tip portion 103 is fixed to a tip of the ultrasonic horn 101. Opposing surfaces of the horn tip portion 103 and the anvil 102 are formed as wire compression surfaces 103a and 102a. Irregularities 104 for effectively transmitting ultrasonic vibrations to the electric wires are formed on the entire surfaces of the electric wire compression surfaces 103a and 102a.
[0004]
Next, the procedure of ultrasonic welding will be described. The plurality of electric wires W to be connected are peeled off from the insulating sheath 110 at the connection point, and the core wire 111 is exposed to be disposed between the horn tip portion 103 and the anvil 102. It is sandwiched between the part 103 and the anvil 102. Then, compressive force F and ultrasonic vibration (V direction) are applied to the core wires 111 of the plurality of electric wires W by the horn tip portion 103 and the anvil 102. At this time, the core wire 111 of the electric wire W is melted by the ultrasonic energy, and a welded portion 105 (shown in FIGS. 11 to 13) is formed at that portion.
[0005]
FIG. 11A shows a state before welding each end of six electric wires W in which two electric wires W are arranged from four electric wires W in opposite directions, and FIG. It is a perspective view showing welding part 105 of electric wire W formed by the method. FIG. 12A shows a state before exposing a part of the core wire 111 of the electric wire W and welding the two electric wires W to the exposed portion, and FIG. 12B shows a state formed by the above-described method. It is a perspective view which shows the welding part of the electric wire W which was made. FIG. 13A shows a state before welding each end of the four wires W, and FIG. 13B is a perspective view showing a welded portion of the wires W formed by the above-described method.
[0006]
Incidentally, the welded portion 105 formed by ultrasonic welding is required to have welding strength and tensile strength that are not less than predetermined values. As shown in FIGS. 14 (a), (b) and (c), the tensile strength is usually achieved by fixing one electric wire W and pulling the other electric wire W with a predetermined tensile force f.
[0007]
[Patent Document 1]
JP-A-2002-217229
[0008]
[Problems to be solved by the invention]
However, the above-described conventional ultrasonic welding apparatus 100 and its method cannot satisfy both the welding strength and the tensile strength of the welding portion 105.
[0009]
That is, if the welding conditions (compression force, amplitude of vibration, vibration time, etc.) are strengthened, the welding state becomes strong and the welding strength can be increased. However, since the projections of the irregularities 104 of the wire compression surfaces 103a and 102a compress the core wire with a very strong force as compared with other portions, the surface of the welding portion 105 has the wire compression surface 103a as shown in FIG. , 102a is formed with a groove 112 which is pierced by the protrusion of the unevenness 104. Due to the formation of the groove 112, the core wire 111 is degraded (U-shaped plastic deformation of the core wire 111, diameter reduction of the core wire 111, etc.), and the tensile strength is reduced. Particularly, when the diameter of the strand 111a constituting the core wire 111 is small, the influence of the biting of the convex portion is large, and the tensile strength is likely to be reduced.
[0010]
Conversely, when the welding conditions (compression force, vibration amplitude, vibration time, etc.) are weakened, the force for compressing the core wire is not so strong even at the convex portions of the irregularities 104 of the electric wire compression surfaces 103a, 102a. The groove 112 is hardly formed due to the bite of the portion, and the tensile strength is maintained. However, there is a possibility that the welding state of the welded portion 105 does not become strong and the welding strength becomes weak.
[0011]
Then, this invention was made in order to solve the said subject, and provides the ultrasonic welding apparatus and the ultrasonic welding method of the electric wire which can improve both the welding strength and the tensile strength of a welding part. With the goal.
[0012]
[Means for Solving the Problems]
According to the first aspect of the present invention, a plurality of electric wires are arranged between a horn tip portion of an ultrasonic horn and an anvil, and a plurality of the electric wires are welded by applying a compressive force and ultrasonic vibration to the plurality of electric wires. An ultrasonic welding apparatus for an electric wire forming a portion, wherein the horn tip portion and the electric wire compression surface of any one of the anvil are provided with a welding strength maintaining surface having irregularities formed thereon and adjacent to the welding strength maintaining surface. An ultrasonic welding apparatus for an electric wire, further comprising: a tensile strength maintaining surface that retreats from the welding strength maintaining surface on a side opposite to the electric wire compression direction.
[0013]
In this ultrasonic welding apparatus for electric wires, the area of the electric wire compressed on the welding strength maintaining surface receives a strong compressive force, so that the welding state is strengthened, and the area of the electric wire compressed on the tensile strength maintaining surface is welded. Since the compressive force is weaker than the corresponding area of the strength maintaining surface, the welding strength is lower than the welding strength maintaining surface, but the wire hardly deteriorates and the tensile strength is maintained. Therefore, a portion having high welding strength and a portion having high tensile strength are formed in the welded portion.
[0014]
The invention according to claim 2 is the ultrasonic welding apparatus for electric wires according to claim 1, wherein the tensile strength maintaining surface is a flat surface.
[0015]
In the ultrasonic welding apparatus for an electric wire, in addition to the effect of the first aspect of the present invention, in the area of the electric wire compressed on the surface where the tensile strength is maintained, the deformation of the electric wire due to the indentation of the projections of the unevenness does not occur.
[0016]
The invention according to claim 3 is the ultrasonic welding apparatus for an electric wire according to claim 1 or 2, wherein the welding strength maintaining surface and the welding strength maintaining surface are provided on the electric wire compression surfaces of both the horn tip portion and the anvil. An ultrasonic welding apparatus for an electric wire, wherein a tensile strength maintaining surface is provided.
[0017]
In the ultrasonic welding apparatus for an electric wire, in addition to the operation of the first or second aspect of the invention, a welded portion is formed more efficiently.
[0018]
The invention according to claim 4 is the ultrasonic welding apparatus for an electric wire according to any one of claims 1 to 3, wherein the tensile strength maintaining surface is an electric wire from a side adjacent to the welding strength maintaining surface. An ultrasonic welding apparatus for an electric wire, characterized in that it has a tapered shape that gradually retreats to the opposite side of the compression direction.
[0019]
In the ultrasonic welding apparatus for an electric wire, in addition to the effects of the first to third aspects, the compressive force is gradually reduced from the area corresponding to the welding strength maintaining surface to the area corresponding to the tensile strength maintaining surface. I do.
[0020]
According to a fifth aspect of the present invention, in the ultrasonic welding apparatus for an electric wire according to any one of the first to third aspects, the tensile strength maintaining surface is opposite to the electric wire compression direction than the welding strength maintaining surface. An ultrasonic welding apparatus for an electric wire, wherein the ultrasonic welding apparatus has a straight shape that retreats one step to a side.
[0021]
In this ultrasonic welding apparatus for electric wires, in addition to the same operation as the first to third aspects of the present invention, not only the tensile strength of the tensile strength maintaining surface but also the welding strength is maintained.
[0022]
According to a sixth aspect of the present invention, in the ultrasonic welding apparatus for an electric wire according to any one of the first to fifth aspects, the tensile strength maintaining surface is disposed closer to the wire drawing side than the welding strength maintaining surface. An ultrasonic welding apparatus for electric wires, characterized in that:
[0023]
In the ultrasonic welding apparatus for an electric wire, in addition to the effects of the inventions of the first to fifth aspects, in the welded portion, the area where the welding state is strong in the wire drawing direction, the welding state is weak, and the tensile strength is maintained. They are arranged in the order of the areas.
[0024]
The invention according to claim 7 is the ultrasonic welding apparatus for an electric wire according to claim 6, wherein the electric wire compression surface is located at a position closer to the electric wire drawing side than the tensile strength maintaining surface, and the electric wire is more than the tensile strength maintaining surface. An ultrasonic welding apparatus for an electric wire, wherein an electric wire diameter return surface that gradually retreats is provided on the opposite side of the electric wire compression direction.
[0025]
In this ultrasonic welding apparatus for electric wires, in addition to the effect of the invention of claim 6, the welded portion is formed in the order of the area where the welding state is strong, the area where the welding state is weak, and the area where the welding state is very weak in the wire drawing direction. Are arranged. That is, it is possible to gradually return to the normal core wire diameter from the welded portion.
[0026]
The invention according to claim 8 is that a plurality of electric wires are arranged between the horn tip portion of the ultrasonic horn and the anvil, and a compressive force and ultrasonic vibration are applied to the plurality of electric wires to weld the plurality of electric wires by melting. An ultrasonic welding method of an electric wire forming a portion, wherein a compressive force is applied to a plurality of the electric wires arranged between the horn tip portion and the anvil by dividing the electric wire into a strong compression area and a weak compression area. An ultrasonic welding method for electric wires, characterized in that:
[0027]
In this method of ultrasonic welding of electric wires, a portion having a high welding strength and a portion having a high tensile strength are formed at the welded portion.
[0028]
The invention according to claim 9 is the ultrasonic welding method for electric wires according to claim 8, wherein a side farther from the wire drawing side is a strong compression area, and a side closer to the wire drawing side is a weak compression area. This is an ultrasonic welding method for electric wires.
[0029]
In this ultrasonic welding method for electric wires, in addition to the effect of the invention of claim 8, the welded portions are arranged in the order of the area where the welding state is strong and the area where the welding state is weak in the wire drawing direction.
[0030]
According to a tenth aspect of the present invention, there is provided the ultrasonic welding method of the electric wire according to the ninth aspect, wherein the electric wire is further pulled out from the weakly compressed area with a smaller compressive force than the weakly compressed area and further away from the weakly compressed area. The present invention provides an ultrasonic welding method for electric wires, characterized by gradually applying a weak compressive force in accordance with the following.
[0031]
In this ultrasonic welding method for electric wires, in addition to the effect of the ninth aspect of the present invention, the welded portions are arranged in the order of the area where the welding state is strong, the area where the welding state is normal, and the area where the welding state is weak in the wire drawing direction. Is done. That is, it is possible to gradually return to the normal core wire diameter from the welded portion.
[0032]
BEST MODE FOR CARRYING OUT THE INVENTION
Hereinafter, embodiments of the present invention will be described with reference to the drawings.
[0033]
<First embodiment>
1 to 5 show a first embodiment of the present invention. FIG. 1 is a perspective view of a main part of an ultrasonic welding apparatus 1, and FIG. 2 is an enlarged view of a horn tip portion 4 and electric wire compression surfaces 4 a and 3 a vicinity of an anvil 3. FIG. 3 is a side view, FIG. 3 is a perspective view showing a welded portion 13 of the electric wire W created by ultrasonic welding, FIG. 4 is a schematic cross-sectional view taken along line AA of FIG. 3, and FIG. FIG. 5B is a schematic cross-sectional view taken along line B2-B2 in FIG. 4, and FIG. 5C is a schematic cross-sectional view taken along line B3-B3 in FIG.
[0034]
As shown in FIG. 1, the ultrasonic welding device 1 includes an ultrasonic horn 2 disposed above and an anvil 3 disposed below the ultrasonic horn 2. The ultrasonic horn 2 has a horn tip portion 4 at the tip thereof, and the horn tip portion 4 is provided so as to be movable between a welding position where it is pressed against the anvil 3 and a standby position where it is separated above the anvil 3. Have been. At the welding position, it can be pressed against the anvil 3 with a predetermined compression force F. The vibration direction of the ultrasonic waves by the ultrasonic horn 2 is set in the axial direction of the electric wire W sandwiched between the horn tip portion 4 and the anvil 3 (the direction of the arrow V in FIG. 1).
[0035]
The anvil 3 has an upper surface surrounded by left and right side wall portions 5, and the upper surface and the lower surface of the horn tip portion 4 are arranged to face each other. The opposing lower surface of the horn tip portion 4 and the upper surface of the anvil 3 are formed as wire compression surfaces 4a, 3a.
[0036]
As shown in detail in FIG. 2, the electric wire compression surfaces 4 a and 3 a are respectively weld strength maintaining surfaces 6, are adjacent to the weld strength maintenance surfaces 6, and are opposite to the welding strength maintenance surfaces 6 in the wire compression direction (horns). A tensile strength maintaining surface 7 that retreats to the upper side on the wire compressing surface 4a of the tip portion 4 and a lower side on the electric wire compressing surface 3a of the anvil 3), and is adjacent to the tensile strength maintaining surface 7 and at the same time. And the wire diameter return surface 8 formed continuously from the adjacent side. The welding strength maintaining surface 6, the tensile strength maintaining surface 7, and the wire diameter returning surface 8 are arranged in this order in the wire drawing direction S.
[0037]
Irregularities 10 are formed on each welding strength maintaining surface 6 by cutting serration grooves. The convex portions (particularly, without reference numerals) and the concave portions (particularly, without reference numerals) formed by the serration grooves are alternately arranged along the axial direction of the electric wire W, and each of the alternately arranged ones is formed. The convex portion and each concave portion extend in a direction orthogonal to the axial direction of the electric wire W, respectively. The unevenness 10 may be formed by forming a knurl groove or the like.
[0038]
Each of the tensile strength maintaining surfaces 7 is a flat surface on which no irregularities are formed, and is formed as a straight tapered surface that gradually retreats from the welding strength maintaining surface 6 to the opposite side in the wire compression direction.
[0039]
Each wire diameter return surface 8 is a flat surface on which no irregularities are formed, and is formed as a curved tapered surface that gradually retreats from the tensile strength maintaining surface 7 to the opposite side in the wire compression direction.
[0040]
Next, the procedure of ultrasonic welding will be described. An example in which the respective ends of the four electric wires W are ultrasonically welded will be described.
[0041]
As shown in FIG. 1, first, the insulating sheaths 11 at the end portions of the four electric wires W are peeled off, and the core wires 12 are respectively exposed. The core wire 12 is an aggregate of many strands 12a. Then, the core wires 12 of the four electric wires W are placed on the electric wire compression surface 3a of the anvil 3 in a state of being collected. Next, the horn tip portion 4 of the ultrasonic horn 2 is shifted from the standby position to the welding position, and the horn tip portion 4 and the anvil 3 sandwich the core wires 12 of the four electric wires W. Next, a compressive force F and ultrasonic vibration (V direction) are applied to the core wire 12 held between the horn tip portion 4 and the anvil 3 for a predetermined time. At this time, ultrasonic waves are transmitted to the core wires 12 of the four electric wires W sandwiched between the horn tip portion 4 and the anvil 3, via the electric wire compression surfaces 4a, 3a, and ultrasonic energy is applied. The core energy 12 of the electric wire W is melted by the ultrasonic energy, and the welded portion 13 shown in FIG. 3 is formed by cooling the melted portion. Thereby, the four electric wires W are electrically connected.
[0042]
A strong compressive force acts on the area L1 of the core wire 12 compressed between the two welding strength maintaining surfaces 6, and high ultrasonic energy is applied since ultrasonic vibration is effectively transmitted by the unevenness 10. For this reason, as shown in FIG. 4 (range of L1) and FIG. 5A, this area L1 is an area where the welding state is strong and the welding strength is high. In addition, a groove 15 is formed on the surface of the area L1 corresponding to the welding strength maintaining surface 6, as shown in FIGS.
[0043]
On the other hand, since weak compressive force acts on the area L2 of the core wire 12 compressed between the two tensile strength maintaining surfaces 7 as compared with the corresponding area of the welding strength maintaining surface 6, weak ultrasonic energy is applied. Can be Therefore, as shown in FIG. 4 (range of L2) and FIG. 5B, this area L2 is an area having a high tensile strength because the welding state is weak and the core wire 12 is less damaged.
[0044]
Further, an extremely weak ultrasonic energy is applied to the area L3 of the core wire 12 compressed between the two electric wire diameter return surfaces 8, since a weaker compressive force acts on the area L3 than the tensile strength maintaining surface 7. For this reason, in this area L3, as shown in FIG. 4 (range of L3) and FIG. 5C, the welding state is very weak, and the normal core wire diameter in which the shape of the wire 12a of the core wire 12 is almost maintained is maintained. It is in a state close to.
[0045]
As described above, since a portion having high welding strength and a portion having high tensile strength are formed in the welded portion 13, both the welding strength and the tensile strength of the welded portion 13 can be improved.
[0046]
As described above, in the above-described first embodiment, since the tensile strength maintaining surface 7 is a flat surface, the area L2 of the core wire 12 compressed by the tensile strength maintaining surface 7 has, as shown in FIG. Since the core wire 12 is not deformed due to the bite of the portion, the tensile strength is maintained. In particular, in the conventional example, the tensile strength could not be increased with respect to the wire 12a constituting the core wire 12 having a small diameter, but in the present invention, the tensile strength maintaining surface 7 has no bite by the convex portion, and Even when the diameter of 12a is small, the tensile strength can be effectively improved.
[0047]
In the first embodiment, the tensile strength maintaining surface 7 has a straight tapered shape that gradually retreats from the side adjacent to the welding strength maintaining surface 6 to the opposite side in the wire compression direction. Is gradually reduced from the area L1 corresponding to the area L2 to the area L2 corresponding to the tensile strength maintaining surface 7. Therefore, there is no place in the welded portion 13 where the welding state is extremely changed.
[0048]
Further, in the first embodiment, the electric wire compression surfaces 4a and 3a are arranged on the wire drawing side from the tensile strength maintaining surface 7 together with the welding strength maintaining surface 6 and the tensile strength maintaining surface 7, and the tensile strength maintaining surface 7 Since the wire diameter return surface 8 that gradually retreats on the opposite side in the wire compression direction is provided, in the welded portion 13, as shown in FIG. The weak area L2 and the area L3 where the welding state is very weak are arranged in this order. That is, it is possible to gradually return to the normal core wire diameter from the welded portion 13. Therefore, it is possible to prevent the core wire diameter at the boundary between the welded portion 13 and the portion not to be welded from being extremely changed.
[0049]
In the above-described first embodiment, the welding strength maintaining surface 6, the tensile strength maintaining surface 7, and the wire diameter returning surface 8 are provided on the wire compression surfaces 4a and 3a of both the horn tip portion 4 and the anvil 3, respectively. The welding strength maintaining surface 6, the tensile strength maintaining surface 7, and the wire diameter returning surface 8 may be provided only on one of the wire compression surfaces 4a, 3a.
[0050]
Further, the wire diameter return surface 8 is formed as a curved tapered surface that gradually retreats from the tensile strength maintaining surface 7 to the opposite side in the wire compression direction, but may be formed as a straight tapered surface.
[0051]
Next, a modified example of the above-described first embodiment will be described.
[0052]
FIG. 6 is a perspective view of a main part of the ultrasonic welding device 21, FIG. 7 is an enlarged side view of the horn tip portion 24 and the vicinity of the electric wire compression surfaces 24a and 23a of the anvil 23, and FIG. It is a perspective view which shows the welding part 33.
[0053]
In this modification, as shown in FIG. 6, the ultrasonic welding device 21 includes an ultrasonic horn 22 disposed above and an anvil 23 disposed below the ultrasonic horn 22. The ultrasonic horn 22 has a horn tip portion 24 at its tip, and the horn tip portion 24 is provided so as to be displaceable between a welding position where it is pressed against the anvil 23 and a standby position where it is separated above the anvil 23. ing. At the welding position, it can be pressed against the anvil 23 with a predetermined compression force F. The vibration direction of the ultrasonic waves by the ultrasonic horn 22 is set in the axial direction of the electric wire W sandwiched between the horn tip portion 24 and the anvil 23 (the direction of the arrow V in FIG. 1).
[0054]
The anvil 23 has an upper surface surrounded by left and right side wall portions 25, and the upper surface and the lower surface of the horn tip portion 24 are arranged to face each other. The lower surface of the horn tip portion 24 and the upper surface of the anvil 23 facing each other are formed as wire compression surfaces 24a, 23a.
[0055]
As shown in detail in FIG. 7, the electric wire compression surfaces 24a and 23a are formed adjacent to both sides of the welding strength maintaining surface 26 and the welding strength maintaining surface 26, respectively. (The upper side of the electric wire compression surface 24a of the horn tip portion 24 and the lower side of the electric wire compression surface 23a of the anvil 23), and the tensile strength maintaining surfaces 27, 27 are adjacent to the tensile strength maintaining surfaces 27, 27. And the tensile strength maintaining surfaces 27, 27 and the wire diameter returning surfaces 28, 28 formed continuously from the adjacent side. The welding strength maintaining surface 26, the tensile strength maintaining surfaces 27, 27, and the wire diameter returning surfaces 28, 28 are arranged so that the wire diameter returning surface 28, the tensile strength maintaining surface 27, The strength maintaining surface 26, the tensile strength maintaining surface 27, and the wire diameter returning surface 28 are arranged in this order.
[0056]
Irregularities 30 are formed on each welding strength maintaining surface 26 by cutting serration grooves. The convex portions (particularly, without reference numerals) and the concave portions (particularly, without reference numerals) formed by the serration grooves are alternately arranged along the axial direction of the electric wire W, and each of the alternately arranged ones is formed. The convex portion and each concave portion extend in a direction orthogonal to the axial direction of the electric wire W, respectively. In addition, the unevenness 30 may be formed by forming a knurl groove or the like.
[0057]
Each wire diameter return surface 28, 28 is a flat surface on which no irregularities are formed, and is formed as a curved tapered surface that gradually retreats from the tensile strength maintaining surfaces 27, 27 to the opposite side in the wire compression direction. Have been.
[0058]
Next, the procedure of ultrasonic welding will be described. The case where the respective ends of the five electric wires W are ultrasonically welded will be described as an example.
[0059]
As shown in FIG. 6, first, the insulating outer sheaths 11 at the end portions of the five electric wires W are peeled off, and the core wires 12 are respectively exposed. The core wire 12 is an aggregate of many strands 12a. Then, the cores 12 of the four electric wires W are placed on the electric wire compression surface 23a of the anvil 23 in a collected state, and one electric wire W is placed from the opposite direction to the four electric wires W. Next, similarly to the first embodiment, the horn tip portion 24 of the ultrasonic horn 22 is shifted from the standby position to the welding position, and the horn tip portion 24 and the anvil 23 hold the core wires 12 of the five electric wires W. I do. Next, a compressive force F and ultrasonic vibration (V direction) are applied to the core wire 12 sandwiched between the horn tip portion 24 and the anvil 23 for a predetermined time. At this time, ultrasonic waves are transmitted to the core wires 12 of the five electric wires W sandwiched between the horn tip portion 24 and the anvil 23 via the electric wire compression surfaces 24a and 23a, and ultrasonic energy acts. The core energy 12 of the electric wire W is melted by the ultrasonic energy, and the welded portion 33 shown in FIG. 8 is formed by cooling the melted portion. Thereby, the five electric wires W are electrically connected.
[0060]
A strong compressive force acts on the area L1 of the core wire 12 compressed between the two welding strength maintaining surfaces 26, and high ultrasonic energy is applied since ultrasonic vibration is effectively transmitted by the unevenness 30. . For this reason, this area L1 has a strong welding state and is an area having high welding strength. As shown in FIG. 8, a groove 35 is formed on the surface of the area L <b> 1 corresponding to the welding strength maintaining surface 26, as a result of the protrusion of the unevenness 30 being cut into the groove 35.
[0061]
On the other hand, compared to the corresponding area of the welding strength maintaining surface 26, a weak compressive force is applied to the areas L2, L2 of the core wire 12 compressed between the two tensile strength maintaining surfaces 27, 27, so Sonic energy is applied. Therefore, these areas L2, L2 are areas having a high tensile strength because the welding state is weak and the core wire 12 is less damaged.
[0062]
Since weaker compressive force acts on the areas L3, L3 of the core wire 12 compressed between the wire return surfaces 28, 28 than the tensile strength maintaining surfaces 27, 27, the ultrasonic waves are very weak. Energy is added. Therefore, in the areas L3 and L3, the welding state is very weak, and the shape of the element wire 12a of the core wire 12 is almost the same as the normal core wire diameter.
[0063]
As described above, since a portion having high welding strength and a portion having high tensile strength are formed in the welded portion 33, both the welding strength and the tensile strength of the welded portion 33 can be improved.
[0064]
As described above, in the modified example of the above-described first embodiment, the same effect as that of the first embodiment can be obtained, and the tensile strength maintaining surface 27 and the electric wire are provided on the wire drawing side and the distal end side of the welding strength maintaining surface 26. Since the diameter return surface 28 is provided, the core wire diameter at the boundary between both sides of the formed welded portion 33 and the portion not to be welded is prevented from being extremely changed, and the welding state of the welded portion 33 is extremely switched. No spots occur. Also, even if the electric wire W is supplied from both directions of the electric wire drawing side and the electric wire tip side, the electric wire W can be effectively welded, and the degree of freedom of the welded portion is improved.
[0065]
In the modification of the first embodiment described above, the welding strength maintenance surface 26, the tensile strength maintenance surface 27, and the wire diameter return surface 28 are respectively provided on the wire compression surfaces 24a and 23a of both the horn tip portion 24 and the anvil 23. Although provided, the welding strength maintaining surface 26, the tensile strength maintaining surface 27, and the wire diameter returning surface 28 may be provided only on one of the electric wire compression surfaces 24a and 23a.
[0066]
The wire diameter return surface 28 is formed as a curved tapered surface that gradually retreats from the tensile strength maintaining surface 27 to the opposite side in the wire compression direction, but may be formed as a straight tapered surface.
[0067]
<Second embodiment>
FIG. 9 shows the second embodiment of the present invention, and is an enlarged side view of the horn tip portion 4 and the vicinity of the wire compression surfaces 4a, 3a of the anvil 3. Comparing the second embodiment with the first embodiment, the tensile strength maintaining surface 7a formed on the electric wire compression surfaces 4a, 3a has a straight shape that retreats one step from the welding strength maintenance surface 6 to the opposite side in the electric wire compression direction. It is provided in. The other configuration is the same as that of the first embodiment, and the description is omitted.
[0068]
Also in the second embodiment, substantially the same operation and effect as those in the first embodiment can be obtained, and the core wire diameter at the boundary between the formed welded portion and the unwelded portion is prevented from being extremely changed. In the welded portion, there is no place where the welding state is extremely changed. Further, when the wire diameter return surface 8 is formed on the wire compression surfaces 4a, 3a, even if the tensile strength maintaining surface 7a has a straight shape, the formed welded portion should maintain sufficient tensile strength. Can be. Further, since the tensile strength maintaining surface 7a has a straight shape, the welding strength is maintained as compared with the case where the tensile strength maintaining surface is formed in a tapered shape.
[0069]
As in the modification of the first embodiment described above, a tensile strength maintaining surface and a wire diameter returning surface may be provided on the wire drawing side of the welding strength maintaining surface 6 and on the distal end side of the wire.
[0070]
【The invention's effect】
As described above, according to the first aspect of the present invention, the area of the electric wire compressed on the welding strength maintaining surface receives a strong compressive force, so that the welding state becomes strong, and the area is compressed on the tensile strength maintaining surface. In the area of the electric wire, only a weak compressive force is applied as compared with the corresponding area of the welding strength maintaining surface, so that the welding strength is weak, and the electric wire hardly deteriorates. Therefore, since a portion having high welding strength and a portion having high tensile strength are formed in the welded portion, both the welding strength and the tensile strength of the welded portion can be improved.
[0071]
According to the invention of claim 2, in addition to the effect of the invention of claim 1, in the area of the electric wire compressed on the tensile strength maintaining surface, the deformation of the electric wire due to the indentation of the convex and concave portions does not occur, so that the tensile strength Is further improved.
[0072]
According to the third aspect of the invention, in addition to the same effect as the first or second aspect of the invention, a welded portion can be formed more efficiently.
[0073]
According to the fourth aspect of the present invention, in addition to the effects of the first to third aspects, the compressive force gradually decreases from the area corresponding to the welding strength maintaining surface to the area corresponding to the tensile strength maintaining surface. . Therefore, there is no place in the welded portion where the welding state is extremely switched.
[0074]
According to the fifth aspect of the present invention, in addition to the same effects as the first to third aspects of the present invention, since the tensile strength maintaining surface has a straight shape, not only the tensile strength of the tensile strength maintaining surface but also the welding strength is improved. Will be maintained.
[0075]
According to the invention of claim 6, in addition to the effects of the invention of claims 1 to 5, the welded portions are arranged in the order of the area where the welding state is strong and the area where the welding state is not strong in the wire drawing direction. . Therefore, it is possible to prevent the core wire diameter at the boundary between the welded portion and the portion not to be welded from being extremely changed.
[0076]
According to the invention of claim 7, in addition to the effect of the invention of claim 6, the welded portion is arranged in the order of the area where the welding state is strong, the area where the welding state is weak, and the area where the welding state is very weak in the wire drawing direction. Are arranged. That is, since the diameter of the core wire can be gradually returned from the welded portion to the normal core wire diameter, it is possible to effectively prevent the core wire diameter at the boundary with the portion not welded from the welded portion from changing.
[0077]
According to the invention of claim 8, since a portion having a high welding strength and a portion having a high tensile strength are formed in the welded portion, both the welding strength and the tensile strength of the welded portion can be improved.
[0078]
According to the ninth aspect of the invention, in addition to the effect of the eighth aspect, the welded portions are arranged in the order of the area where the welding state is strong and the area where the welding state is weak in the wire drawing direction. Therefore, it is possible to prevent the core wire diameter at the boundary between the welded portion and the portion not to be welded from being extremely changed.
[0079]
According to the tenth aspect, in addition to the effect of the ninth aspect, the welded portions are arranged in the order of the area where the welding state is strong, the area where the welding state is normal, and the area where the welding state is weak in the wire drawing direction. Is done. That is, since the diameter of the core wire can be gradually returned from the welded portion to the normal core wire diameter, it is possible to effectively prevent the core wire diameter at the boundary with the portion not welded from the welded portion from changing.
[Brief description of the drawings]
FIG. 1 shows a first embodiment of the present invention and is a perspective view of a main part of an ultrasonic welding apparatus.
FIG. 2 shows the first embodiment of the present invention, and is an enlarged side view near a wire compression surface of a horn tip portion and an anvil.
FIG. 3 is a perspective view showing the first embodiment of the present invention and showing a welded portion of an electric wire produced by ultrasonic welding.
FIG. 4 shows the first embodiment of the present invention, and is a schematic cross-sectional view taken along line AA of FIG. 3;
5A and 5B show a first embodiment of the present invention, in which FIG. 5A is a schematic sectional view taken along line B1-B1 of FIG. 4, FIG. 5B is a schematic sectional view taken along line B2-B2 of FIG. FIG. 5C is a schematic sectional view taken along line B3-B3 in FIG.
FIG. 6 shows a modification of the first embodiment of the present invention, and is a perspective view of a main part of an ultrasonic welding device.
FIG. 7 is an enlarged side view showing a modified example of the first embodiment of the present invention and showing the vicinity of a wire compression surface of a horn tip portion and an anvil.
FIG. 8 is a perspective view showing a modification of the first embodiment of the present invention and showing a welded portion of an electric wire produced by ultrasonic welding.
FIG. 9 is an enlarged side view of the horn tip portion and the vicinity of a wire compression surface of the anvil according to the second embodiment of the present invention.
FIG. 10 shows a conventional example and is a perspective view of a main part of an ultrasonic welding apparatus.
11 (a) shows a conventional example, and FIG. 11 (a) shows a state before welding each end of six electric wires W in which two electric wires W are arranged from four electric wires W in opposite directions. FIG. 11B is a perspective view showing a welded portion of the electric wire W formed by ultrasonic welding.
FIG. 12A shows a conventional example, and FIG. 12A shows a state before exposing a part of the core wire of the electric wire W and welding two electric wires W to the exposed portion. () Is a perspective view showing a welded portion of the electric wire W formed by ultrasonic welding.
13A and 13B show a conventional example, in which FIG. 13A shows a state before welding each end of four wires W, and FIG. 13B shows a state of the wires W formed by ultrasonic welding. It is a perspective view which shows a welding part.
14 (a) to 14 (c) are perspective views showing a state of a tensile test of a welded portion of an electric wire in various welding modes.
FIG. 15 shows a conventional example and is a schematic sectional view of a welded portion.
[Explanation of symbols]
1 Ultrasonic welding equipment
2 Ultrasonic horn
3 Anvil
3a Wire compression surface
4 Horn tip
4a Wire compression surface
6 Weld strength maintaining surface
7, 7a Tensile strength maintaining surface
8 Wire diameter return surface
10 unevenness
13 Welds
W twisted electric wire (electric wire)

Claims (10)

A plurality of electric wires are arranged between a horn tip portion of the ultrasonic horn and the anvil, and a compressive force and ultrasonic vibration are applied to the plurality of electric wires to form a welded portion by melting the plurality of electric wires. Sonic welding equipment,
Either the horn tip portion or the wire compression surface of the anvil has an uneven welding strength maintaining surface and a surface adjacent to the welding strength maintaining surface and opposite to the wire compression direction from the welding strength maintaining surface. An ultrasonic welding apparatus for an electric wire, comprising a tensile strength maintaining surface that retreats on a side. The ultrasonic welding apparatus for an electric wire according to claim 1,
An ultrasonic welding apparatus for electric wires, wherein the tensile strength maintaining surface is a flat surface. An ultrasonic welding apparatus for an electric wire according to claim 1 or claim 2,
An ultrasonic welding apparatus for electric wires, wherein the welding strength maintaining surface and the tensile strength maintaining surface are provided on the electric wire compression surfaces of both the horn tip portion and the anvil. It is an ultrasonic welding apparatus of the electric wire according to any one of claims 1 to 3,
The ultrasonic welding apparatus for electric wires, wherein the tensile strength maintaining surface has a tapered shape that gradually retreats from a side adjacent to the welding strength maintaining surface to a side opposite to the electric wire compression direction. It is an ultrasonic welding apparatus of the electric wire according to any one of claims 1 to 3,
The ultrasonic welding apparatus for electric wires, wherein the tensile strength maintaining surface has a straight shape that retreats one step to a side opposite to the electric wire compression direction from the welding strength maintaining surface. An ultrasonic welding apparatus for an electric wire according to any one of claims 1 to 5,
The ultrasonic welding apparatus for an electric wire, wherein the tensile strength maintaining surface is disposed closer to the wire drawing side than the welding strength maintaining surface. An ultrasonic welding apparatus for an electric wire according to claim 6,
The electric wire compression surface is provided with an electric wire diameter return surface that is gradually retreated at a position on the electric wire drawing side from the tensile strength maintenance surface and on the opposite side of the electric wire compression direction from the tensile strength maintenance surface. Ultrasonic welding equipment for electric wires. A plurality of electric wires are arranged between a horn tip portion of the ultrasonic horn and the anvil, and a compressive force and ultrasonic vibration are applied to the plurality of electric wires to form a welded portion by melting the plurality of electric wires. A sonic welding method,
An ultrasonic welding method for an electric wire, wherein a compressive force is applied to a plurality of electric wires arranged between the horn tip portion and the anvil in a strong compression area and a weak compression area. An ultrasonic welding method for an electric wire according to claim 8,
An ultrasonic welding method for electric wires, characterized in that a side farther from the wire outlet side is a strong compression area and a side closer to the wire outlet side is a weak compression area. An ultrasonic welding method for an electric wire according to claim 9,
An ultrasonic welding method for an electric wire, further comprising applying a weaker compressive force to the wire drawing side than the weakly compressed area with a weaker compressive force than the weakly compressed area and gradually increasing the distance from the weakly compressed area. .

Images