JP5474424B2 - Ultrasonic welding method and ultrasonic welding apparatus - Google Patents

Description

The present invention relates to an ultrasonic welding method and an ultrasonic welding apparatus, and more particularly to an ultrasonic welding method and an ultrasonic welding apparatus for ultrasonic welding a core wire composed of a plurality of strands to a terminal fitting. It is.

  Various electronic devices are mounted on an automobile as a moving body. In the automobile, a wire harness is routed to transmit power from a power source such as a battery or a control signal from a control device to the electronic device. The wire harness described above includes a plurality of electric wires and terminal fittings attached to the ends of the electric wires.

  Each of the electric wires includes a core wire obtained by twisting a plurality of conductive strands and an insulating covering portion that covers the core wire. The core wire exposed by removing the covering portion of the end of the electric wire is welded to the terminal fitting. The welding between the core wire and the terminal fitting is performed using a known ultrasonic welding apparatus.

  As the ultrasonic welding apparatus 1, for example, the one shown in FIG. 9 is known. As shown in the figure, the ultrasonic welding apparatus 1 includes an anvil 10 as a first mold on which a terminal fitting 3 having a core wire 21 superimposed on a bottom wall portion 32 a is mounted, and a second facing the anvil 10. And a horn 11 as a mold. The horn 11 is given ultrasonic vibration by a vibrator (not shown). The ultrasonic welding apparatus 1 inserts the horn 11 between a pair of standing wall portions 32b provided on the terminal fitting 3 and moves the horn 11 toward the anvil 10 as indicated by an arrow. As a result, the core wire 21 and the bottom wall portion 32a of the terminal fitting 3 are sandwiched between the horn 11 and the anvil 10, and ultrasonic energy is applied in a state where the core wire 21 and the terminal fitting 3 are pressed in a direction approaching each other. The core wire 21 and the terminal fitting 3 are welded.

  When the core wire 21 is welded in a shape (for example, a straight stretched state) different from the twisted rod, a force to return to the original spiral state works, and as a result, the strands are scattered and the core wire 21 and the terminal There exists a possibility that the welding strength with the metal fitting 3 may fall. Therefore, by removing the covering portion of the terminal and exposing the core wire 21, each element wire is overlapped and welded on the terminal fitting 3 in a state of being twisted spirally according to its own twisted rod, An ultrasonic welding method that suppresses variations in the strands has also been proposed (Patent Document 1).

  However, the conventional ultrasonic welding apparatus 1 is provided such that the width W4 of the horn 11 is shorter than the width W5 between the pair of standing wall portions 32b. For this reason, when the horn 11 is inserted between the pair of standing wall portions 32b and is moving toward the anvil 10, there is a gap between the horn 11 and the standing wall portion 32b, and the strands are removed from the gap and the core wire is removed. There has been a problem that welding leakage occurs between the terminal 21 and the terminal fitting 3.

JP-A-2005-340106

The present invention, ultrasonic welding method without welding leakage between the core wire and the terminal fitting, and, it is an object to provide an ultrasonic welding equipment.

The invention according to claim 1, which has been made to solve the above-described problems, mounts a terminal wall provided with a bottom wall portion and a pair of standing wall portions erected from both ends of the bottom wall portion on the first mold. A first step, a second step of superimposing a core wire composed of a plurality of strands on the bottom wall portion of the terminal fitting, and a second die inserted between the pair of standing wall portions toward the first die. By moving the core wire and the terminal fitting between the first die and the second die, ultrasonic energy is applied in a state where the core wire and the terminal fitting are pressed in a direction approaching each other. and a third step of welding the said and the core wire terminal fitting, in the ultrasonic welding method for performing, while widening in the third direction and the second mold in the process away from each other said pair of vertical wall portions Moving the second mold toward the first mold. It resides in the ultrasonic welding method to the symptoms.

  According to a second aspect of the present invention, the second mold is provided so that the width in the direction in which the pair of standing wall portions face each other increases as the distance from the end face facing the first mold increases. It exists in the ultrasonic welding method of Claim 1.

  Invention of Claim 3 is provided so that the width | variety between a pair of standing wall part may become wide as the pair of standing wall part leaves | separates from the said bottom wall part, It is characterized by the above-mentioned. Exist in the ultrasonic welding method.

  According to a fourth aspect of the present invention, there is provided a first wall on which a terminal wall provided with a bottom wall portion in which core wires composed of a plurality of strands are overlapped and a pair of standing wall portions standing from both ends of the bottom wall portion is mounted. A mold and a second mold opposite to the first mold, the second mold being inserted between a pair of standing wall portions and moved toward the first mold to move the first mold The core wire and the terminal fitting are sandwiched between the die and the second die, and ultrasonic energy is applied in a state where the core wire and the terminal fitting are pressed in a direction approaching each other, and the core wire and the terminal In the ultrasonic welding apparatus for welding the metal fitting, the second mold is provided so that the width in the direction in which the pair of standing wall portions face each other increases as the distance from the end surface facing the first mold increases. It exists in the ultrasonic welding apparatus characterized by this.

  As described above, according to the first and fourth aspects of the invention, the second mold moves while expanding the pair of standing wall portions of the terminal fitting. Therefore, there is no gap between the second mold and the pair of standing wall portions, and even if the core wire is frayed, the core wire can be removed from between the terminal fitting and the second mold as long as it is between the pair of standing wall portions. In addition, it is possible to eliminate welding leakage between the core wire and the terminal fitting.

  According to the second aspect of the present invention, the second mold can be simply provided by simply providing the second mold so that the width in the direction in which the pair of standing wall portions face each other increases as the distance from the end face facing the first mold increases. The mold can be moved while expanding the pair of standing wall portions of the terminal fitting.

  According to the third aspect of the present invention, the second mold can be simply provided with the pair of standing walls of the terminal fitting by simply providing the pair of standing walls so that the width between the pair of standing walls increases as the distance from the bottom wall increases. You can move while expanding the part.

It is a perspective view which shows the ultrasonic welding apparatus of this invention in the state which mounted the core wire and terminal metal fitting on a 1st electrode before welding. It is the X section enlarged view of FIG. It is a perspective view which shows the ultrasonic welding apparatus shown in FIG. 1 in the state which pinched | interposed the core wire and the terminal metal fitting with the 1st electrode and the 2nd electrode. FIG. 3 is an enlarged view of a Y part in FIG. 2. It is a perspective view which shows the ultrasonic welding apparatus shown in FIG. 1 in the state which separated the 2nd electrode from the 1st electrode after ultrasonically welding a core wire and a terminal metal fitting. It is the Z section enlarged view of FIG. It is a perspective view which shows the core wire and terminal metal fitting before welding. It is a perspective view which shows the core wire and terminal metal fitting after welding. It is a figure which shows an example of the conventional ultrasonic welding apparatus.

  Hereinafter, embodiments of the present invention will be described with reference to FIGS. The ultrasonic welding apparatus 1 shown in FIGS. 1-6 is used in order to electrically connect the core wire 21 and the terminal metal fitting 3 of the electric wire 2 mutually. As shown in FIG. 7, the electric wire 2 has a round cross section. The electric wire 2 includes a core wire 21 composed of a plurality of conductive wires and an insulating covering portion 22. The core wire 21 is made of a conductive metal such as copper or a copper alloy. The covering portion 22 is made of an insulating synthetic resin and covers the core wire 21.

  The terminal fitting 3 is formed by bending a metal plate material punched into a predetermined shape, and includes an electrical connection portion 31 provided with a connection hole 31a electrically connected to an electronic device and the like, and a core wire to which the core wire 21 is welded. A welding portion 32 is provided along the longitudinal direction. The core wire welded portion 32 is provided with a bottom wall portion 32a on which the core wire 21 is overlapped, and a pair of standing wall portions 32b erected from both ends in the width direction of the bottom wall portion 32a. The pair of standing wall portions 32b are provided so that the width between the pair of standing wall portions 32b increases as the distance from the bottom wall portion 32a increases.

  The ultrasonic welding apparatus 1 superimposes the core wire 21 on the bottom wall portion 32a of the terminal fitting 3, pressurizes the core wire 21 and the terminal fitting 3 in a direction approaching each other, and applies ultrasonic vibration energy, thereby providing the core wire 21. And the terminal fitting 3 are welded. 1 to 6, the ultrasonic welding apparatus 1 includes a first electrode 5 as a first mold, a second electrode 6 as a second mold, a pressing jig 7, and a pair of A jig 8 and a base 9 are provided.

  The said 1st electrode 5 is provided in the box shape, and the bottom wall part 32a of the terminal metal fitting 3 is mounted on the end surface facing the 2nd electrode 6 mentioned later. The second electrode 6 is provided in a substantially box shape, and is provided such that the width in the direction Y <b> 1 in which the pair of standing wall portions 32 b face each other increases as the distance from the end surface facing the first electrode 5 increases. Further, as shown in FIG. 2, in the second electrode 6, the width W1 of the end portion on the first electrode 5 side is wider than the width W2 between the pair of standing wall portions 32b on the bottom wall portion 32a side. Is provided. Further, the width W1 of the end portion on the first electrode 5 side in the second electrode 6 is provided to be the same as or slightly smaller than the width W3 between the pair of standing wall portions 32b farthest from the bottom wall portion 32a.

  A vibrator (not shown) is attached to each of the first electrode 5 and the second electrode 6 described above. This vibrator (not shown) vibrates in the axial direction Y2 of the core wire 21 by an oscillator (not shown), and applies ultrasonic vibration in the axial direction Y2 to the first electrode 5 and the second electrode 6. The first electrode 5 and the second electrode 6 are spaced apart in the vertical direction in the figure. The first electrode 5 and the second electrode 6 can sandwich the bottom wall portion 32a of the terminal fitting 3 in which the core wire 21 is overlapped between the end faces facing each other.

  The second electrode 6 is fixed to a pressing jig 7, and is provided so as to be movable in the vertical direction in the figure by the pressing jig 7. The pressing jig 7 is constituted by a piston of a hydraulic cylinder (not shown), for example. The second electrode 6 moves along the vertical direction in the figure when receiving a force from the press jig 7.

  The pair of jigs 8 described above is provided so as to sandwich a direction Y1 in which the pair of standing wall portions 32b of the first electrode 5 face each other. The pair of jigs 8 are provided so as to protrude from the first electrode 5 toward the second electrode 6. Further, the opposing surfaces of the pair of jigs 8 that protrude from the first electrode 5 are tapered such that they face each other as the distance from the first electrode 5 increases. The base 9 is provided in a box shape, and is mounted with the first electrode 5 and the pair of jigs 8 described above.

  A procedure for welding the core wire 21 and the terminal fitting 3 using the ultrasonic welding apparatus 1 having the above-described configuration will be described below. In the initial state of the ultrasonic welding apparatus 1, the first electrode 5 and the second electrode 6 are sufficiently separated. First, the covering portion 22 of the end of the electric wire 2 is peeled off to expose the core wire 21. Next, the bottom wall portion 32a of the terminal fitting 3 is placed on the end surface of the first electrode 5 facing the second electrode 6, and the exposed core wire 21 is overlaid on the bottom wall portion 32a. Thereafter, a vibrator (not shown) is vibrated to apply ultrasonic vibration to the first electrode 5 and the second electrode 6. Further, the press jig 7 is moved from top to bottom, and the second electrode 6 fixed to the press jig 7 is inserted between the pair of standing wall portions 32b as shown in FIGS. As described above, the width W1 of the second electrode 6 is set to be the same as or slightly smaller than the width W3 between the pair of standing wall portions 32b farthest from the bottom wall portion 32a. Therefore, the second electrode 6 is easily inserted between the pair of standing wall portions 32b.

  Further, when the pressing jig 7 is moved downward, the second electrode 6 fixed to the pressing jig 7 moves toward the first electrode 5. As described above, the width between the pair of standing wall portions 32b becomes narrower as it approaches the bottom wall portion 32a. Moreover, the width of the second electrode 6 increases as the distance from the end on the first electrode 5 side increases. Therefore, the second electrode 6 moves toward the first electrode 5 while spreading the pair of standing wall portions 32b away from each other, as indicated by arrows in FIG.

  Further, when the second electrode 6 is moved toward the first electrode 5, as shown in FIGS. 3 and 4, the core wire 21 and the terminal fitting 3 are sandwiched between the first electrode 5 and the second electrode 6, The core wire 21 and the terminal fitting 3 are pressurized in a direction approaching each other. In this state, ultrasonic vibrations of the first electrode 5 and the second electrode 6 are transmitted, and ultrasonic energy is applied to the core wire 21 and the terminal fitting 3. Then, the core wire 21 and the terminal fitting 3 are ultrasonically welded.

  Next, the vibrator is controlled to stop the ultrasonic vibration and the press jig 7 is controlled to stop the pressurization to the core wire 21 and the terminal fitting 3. Thereafter, when the press jig 7 is controlled to move the press jig 7 upward as shown in FIGS. 5 and 6, the second electrode 6 fixed to the press jig 7 is moved from the first electrode 5. Leave. Then, after the first electrode 5 and the second electrode 6 are sufficiently separated, the terminal fitting 3 to which the core wire 21 is welded is taken out between the first electrode 5 and the second electrode 6.

  According to the above-described embodiment, the second electrode 6 moves while pushing the pair of standing wall portions 32 b of the terminal fitting 3. Therefore, there is no gap between the second electrode 6 and the pair of standing wall portions 32b, and the core wire 21 is between the terminal fitting 3 and the second electrode 6 as long as the core wire 21 is frayed as long as it is between the pair of standing wall portions 32b. The welding leakage between the core wire 21 and the terminal fitting 3 can be eliminated.

  Further, according to the above-described embodiment, the second electrode 6 is provided so that the width in the direction Y <b> 1 in which the pair of standing wall portions 32 b oppose as the distance from the end surface facing the first electrode 5 increases. In addition, the pair of standing wall portions 32b are provided such that the width between the pair of standing wall portions 32b increases as the distance from the bottom wall portion 32a increases. Thereby, the 2nd electrode 6 can be easily moved, expanding the pair of standing wall portions 32b of the terminal fitting 3.

  In addition, according to embodiment mentioned above, while providing the 2nd electrode 6 so that the width | variety of the direction Y1 which a pair of standing wall part 32b opposes may become large as it leaves | separates from the end surface facing the 1st electrode 5, a pair of standing wall The part 32b is provided so that the width between the pair of standing wall parts 32b increases as the distance from the bottom wall part 32a increases. However, the present invention is not limited to this. For example, if the second electrode 6 is provided so that the width in the direction Y1 in which the pair of standing wall portions 32b face each other as the distance from the end surface facing the first electrode 5 increases, the pair of standing wall portions 32b is as shown in FIG. As in the conventional case shown in FIG. 2, the width may always be constant along the vertical direction. Further, if the pair of standing wall portions 32b are provided so that the width between the pair of standing wall portions 32b increases as the distance from the bottom wall portion 32a increases, the second electrode 6 is the same as the conventional one as shown in FIG. Alternatively, a constant width may be provided along the vertical direction.

  Further, the above-described embodiments are merely representative forms of the present invention, and the present invention is not limited to the embodiments. That is, various modifications can be made without departing from the scope of the present invention.

3 Terminal fitting 5 First electrode (first type)
6 Second electrode (second type)
21 Core wire 32a Bottom wall part 32b Standing wall part

Claims (4)

A first step of mounting the bottom wall portion and a terminal fitting provided with a pair of standing wall portions standing from both ends of the bottom wall portion on the first mold; and a plurality of elements on the bottom wall portion of the terminal fitting. A second step of superimposing core wires composed of wires, and a second die inserted between the pair of standing wall portions and moved toward the first die to move the first die and the second die A third step of welding the core wire and the terminal fitting by applying ultrasonic energy in a state where the core wire and the terminal fitting are pressed in a direction approaching each other with the core wire and the terminal fitting interposed therebetween; In the ultrasonic welding method of performing,
The ultrasonic welding method, wherein in the third step, the second mold is moved toward the first mold while the second mold spreads the pair of standing wall portions away from each other. The said 2nd type | mold is provided so that the width | variety of the direction which a pair of standing wall part opposes may become large as it leaves | separates from the end surface facing the said 1st type | mold. Ultrasonic welding method. The ultrasonic welding method according to claim 1, wherein the pair of standing wall portions are provided such that a width between the pair of standing wall portions increases as the distance from the bottom wall portion increases. A first mold on which a terminal wall provided with a bottom wall portion on which core wires composed of a plurality of strands are stacked and a pair of standing wall portions standing from both ends of the bottom wall portion is mounted; and the first mold A second mold opposed to the first mold, and the second mold is inserted between a pair of standing wall portions and moved toward the first mold to move the first mold and the second mold. Ultrasonic welding is performed in which the core wire and the terminal fitting are welded to each other by applying ultrasonic energy in a state where the core wire and the terminal fitting are pressed in a direction in which the core wire and the terminal fitting are brought close to each other. In the apparatus, the second mold is provided so that a width in a direction in which the pair of standing wall portions face each other increases as the distance from the end face facing the first mold increases. .

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