CN104937788A - Ultrasonic Bonding Device - Google Patents

Abstract

There is provided an anvil (10) comprising an upper surface (11a) for placing a wire engaging portion (3) of a terminal (1) having a mating terminal connection portion (2) at the front, and It has a wire joint part (3) at its rear; an ultrasonic horn (20) placed above said anvil; and a terminal pressing part (50), which abuts against the upper surface of the anvil when ultrasonic vibration is provided Press down on the wire junction. A heater (60) is disposed in the terminal pressing part (50).

Description

Ultrasonic Bonding Device

technical field

The present invention relates to an ultrasonic bonding device for bonding a terminal and an electric wire by ultrasonic bonding.

Background technique

Generally, when a terminal is bonded to an electric wire using ultrasonic bonding, an ultrasonic bonding device including an anvil on which the terminal is placed on an upper surface and a horn arranged oppositely above the anvil is used, and the terminal and the electric wire are sandwiched between Between the anvil and the horn, so as to provide ultrasonic vibration to the core wire of the wire in the clamped state.

When a terminal is bonded to an electric wire using this type of ultrasonic bonding device, the terminal 301 is placed on the upper surface 311 of the anvil 310 as shown in FIG. 9( a ). In this case, the terminal 301 generally has a mating terminal connection portion 302 at the front for connection to a mating terminal, and a wire joint portion 303 at the rear thereof for joining to an electric wire. Only the wire engagement portion 303 rests on the upper surface 311 of the anvil 310 . Then, the core wire Wa exposed by removing the insulating coating Wb at the end in the electric wire W is placed on the wire joint 303 placed on the anvil 310 .

Then, as shown in FIG. 9(b), the core wire Wa on the wire joint portion 303 is pressed by the pressing surface 321 on the lower surface of the horn 320, and the core wire Wa and the wire joint portion 303 are sandwiched on the anvil. Ultrasonic vibrations are supplied from the horn 320 while between the horn 310 and the horn 320 . In this way, the ultrasonic vibration generates frictional heat between the element wires constituting the core wire Wa or on the contact surface between the core wire Wa and the wire joint portion 303 . Therefore, all the element wires are finally deformed due to thermal softening, so that the core wire Wa and the electric wire joint portion 303 are joined to each other while integrating the core wire Wa.

Incidentally, if the terminal 301 on the anvil 310 vibrates to follow the core wire Wa during ultrasonic bonding, bonding energy becomes weak, thereby creating a possibility of unsatisfactory bonding.

As shown in FIG. 10 , in order to limit this possibility, a method is considered in which the width of the wire engaging portion 303 placed on the anvil 310 is pressed against the anvil 310 by using the pressing step portion 354 of the terminal pressing member 350 The two ends in the direction, so that the ultrasonic horn 320 provides ultrasonic vibrations to the two ends in the above state. In this case, the mutually opposing inner walls 356 of the terminal pressing member 350 are adapted to function as restrictive walls that prevent the core wire Wa from protruding when the core wire Wa is deformed on the wire joint portion 303 having a flat plate shape.

For example, Patent Document 1 discloses a similar example in the case of performing ultrasonic bonding while using the terminal pressing member.

reference list

patent documents

[Patent Document 1] JP-A-2006-114343

Contents of the invention

technical problem

Incidentally, while studying to increase the fastening force between terminals and core wires bonded to each other by ultrasonic bonding, the present inventors have found that the difference in ambient temperature around the joint causes the fastening force between the terminals and core wires to increase. difference. As an example, an experiment was conducted on whether there is a difference in fastening force when the ambient temperature is 10°C and when the ambient temperature is 30°C. Ten samples were compared with each other under the condition that the input energy of the ultrasonic vibration was equal. As a result, as shown in FIG. 11 , the present inventors found that the fastening force increased more when ultrasonic bonding was performed at an ambient temperature of 30° C. than when ultrasonic bonding was performed at an ambient temperature of 10° C.

For example, the results lead to the understanding that if the ambient temperature is raised to 30°C and the temperature of the elements of the ultrasonic bonding apparatus is raised, favorable records can be obtained even when the temperature condition in the space where the ultrasonic bonding apparatus is installed is 10°C. However, considerable costs are unavoidable in order to maintain the elevated temperature in the entire space in which the ultrasonic bonding device is installed. Therefore, it is not practical.

Therefore, the present inventors found the following results upon further intensive research. That is, ultrasonic bonding uses frictional heat generated by input ultrasonic waves between the joining target members to join the joining target members to each other. However, in such a stage that the temperature is low in peripheral parts involved in joining, frictional heat generated by ultrasonic vibration between joining target parts is dissipated to the surroundings in many cases. The dissipation of frictional heat reduces the likelihood that input energy can contribute to engagement. It can be appreciated that the fastening force is thus reduced.

Incidentally, this type of ultrasonic bonding apparatus is used to produce a terminal-incorporated electric wire through a series of processes of performing ultrasonic bonding on core wires to join respective terminals connected to each other in a chain. At this time, during the period from the first product after starting the production of the electric wire incorporating the terminal until the processing of the tenth or more products is completed, the anvil on which the terminal is placed and the anvil for abutting against the anvil The terminal pressing parts of the holder pressing terminals are cooled, thereby causing heat to dissipate to these parts. Then, in the case of processing a tenth product or more, the cooled part gradually warms up to now. Therefore, it is considered that the fastening force increases.

However, while the temperature of the element is gradually increasing in this way, when the terminal is pressed against the anvil by using the terminal pressing member, if a temperature change of the anvil and the terminal pressing member is observed, it is understood as more heat Escaping to the terminal pressing parts. FIG. 12 shows observation results of how the temperatures in the anvil and the terminal pressing member change from the stage immediately after the start of production.

It can be understood from this result that the temperature of the anvil increases in a short time (lower frequency from the start of production of the electric wire incorporating the terminal). In contrast, an increase in the temperature of the terminal pressing member is delayed. Therefore, it was observed that the frictional heat contributing to the joining was dissipated to the terminal pressing member having a low temperature. The reason why the temperature changes between the anvil and the terminal pressing member differ from each other in this way is that the temperature changes mainly depend on the difference in their volumes. As described above, more frictional heat contributing to engagement is dissipated to the terminal pressing member. It can be understood that the above reasons lead to a phenomenon in which the fastening force between the terminal and the core wire becomes weak at the initial stage of production.

The present invention has been made in view of the above circumstances, and an object of the present invention is to provide an ultrasonic bonding device capable of effectively preventing dissipation of frictional heat contributing to bonding by raising the temperature of a terminal pressing member, and which can thereby Improve the fastening force between the terminal and the core wire from the initial stage of production.

solution to the problem

In order to achieve the above object, the ultrasonic bonding apparatus according to the present invention has the following configurations (1) and (2).

(1) An ultrasonic bonding device, comprising:

An anvil comprising an upper surface for placing a wire engaging portion of a terminal including a mating terminal connecting portion at a front portion for connecting to a mating terminal and having a core at a rear portion thereof for engaging to an end portion of an electric wire the wire splice portion of the wire, the wire splice portion;

an ultrasonic horn placed above the anvil and configured to press the core wire placed on the wire joint portion placed on the upper surface of the anvil from above while pressing, engaging the wire joint portion and the core wire with each other by applying ultrasonic vibration to the core wire and a connection portion between the core wire and the wire joint portion;

a terminal pressing member configured to press the wire joint portion against the upper surface of the anvil when the ultrasonic vibration is provided by the ultrasonic horn; and

a heater that heats the terminal pressing member.

(2) In the ultrasonic bonding apparatus having the above configuration (1), the heater is disposed in the terminal pressing member.

According to the ultrasonic bonding apparatus having the above configurations (1) and (2), it is possible to effectively prevent frictional heat from escaping to the terminal pressing member by heating the terminal pressing member in the initial stage when producing an electric wire incorporating a terminal. As a result, the fastening force between the terminal and the core wire can be improved, and the yield of the electric wire incorporating the terminal can be improved.

Beneficial Effects of the Invention

According to the present invention, it is possible to effectively prevent frictional heat contributing to joining from being dissipated by increasing the temperature of the terminal pressing member. As a result, it is possible to increase the fastening force between the terminal and the core wire from the initial stage of starting production.

So far, the present invention has been briefly described. Furthermore, details of the present invention will become clearer if the following embodiments for embodying the present invention (hereinafter, referred to as “embodiments”) are read through with reference to the accompanying drawings.

Description of drawings

Fig. 1 is a perspective view showing a schematic configuration of a main part of an ultrasonic bonding apparatus according to an aspect of the present invention.

2 is a perspective view showing the configuration of a terminal pressing member as a constituent member in the ultrasonic bonding apparatus according to the embodiment of the present invention.

3(a) to 3(c) are views showing the configuration of a terminal pressing member as a constituent member in the ultrasonic bonding apparatus according to the embodiment of the present invention. 3( a ) is a front view, FIG. 3( b ) is a side view of a part shown in section, and FIG. 3( c ) is an enlarged view taken along the arrow in FIG. 3( a ).

4( a ) to 4 ( d ) are views for illustrating a process when a terminal and an electric wire are bonded to each other using the ultrasonic bonding device according to the embodiment of the present invention. 4( a ) is a view showing a state in which the wire engaging portion of the terminal is placed on the anvil, and FIG. 4( b ) is a view showing a state in which the terminal pressing member presses the wire engaging portion of the terminal against the anvil, and FIG. 4(c) is a view showing a state where the core wire of the end portion of the electric wire is placed on the wire joint part, and FIG. A view of a state in which the ultrasonic horn is lowered to provide ultrasonic vibrations.

5( a ) and FIG. 5( b ) are views showing states during the processing shown in FIG. 4( b ). 5( a ) is a plan view of a portion pressed by a terminal pressing member for identifying a terminal, and FIG. 5( b ) is a front view showing a state in which the terminal pressing member presses the terminal.

6( a ) and 6 ( b ) are views showing a product (joining structure) in which a terminal and an electric wire are joined to each other using an ultrasonic joining device according to an embodiment of the present invention. Fig. 6(a) is a perspective view, and Fig. 6(b) is a plan view when viewed from above.

FIG. 7 is a graph for illustrating the advantageous effects of the ultrasonic bonding device according to the embodiment of the present invention. This table shows that when the terminal and the core wire are joined to each other while heating the terminal fixing member in an environment of 10° C., the fastening force increases in the same manner as when the terminal and the core wire are joined to each other in an environment of 40° C.

8(a) to 8(c) are views for illustrating another embodiment of the present invention. Fig. 8(a) is a perspective view showing a product (joining structure) in which a terminal and an electric wire are joined to each other by using the device according to the present invention. 8(b) and 8(c) are views for illustrating processing in producing a product. FIG. 8( b ) is a front front view showing a state where the terminal pressing member is to be lowered in order to press the terminal placed on the anvil against the anvil, and FIG. 8( c ) is a view showing that the terminal pressing member presses the terminal. Front view of the state.

9(a) and 9(b) are views for illustrating examples in the related art. Fig. 9(a) is a perspective view showing a state in which a terminal and a core wire are sandwiched between an anvil and an ultrasonic horn, and Fig. 9(b) is a state showing a state in which ultrasonic bonding is performed in the sandwiched state perspective view.

10 is a sectional view when viewed from the front showing a state in which the terminal pressing member presses the wire bonding portion of the terminal against the anvil during ultrasonic bonding.

Fig. 11 is a graph showing changes in fastening force between a terminal and a core wire according to ambient temperature.

FIG. 12 is a graph showing differences in temperature changes of an anvil and a terminal pressing member according to the number of processing processes when a terminal and a core wire are bonded to each other by ultrasonic bonding.

List of Reference Marks

1 terminal

2 Mating terminal connection part

3 wire junction

10 Anvil

11 upper surface

20 ultrasonic horn

21 Press surface

50 terminal press parts

60 heater

101 terminal

102 Mating terminal connection part

103 Wire junction

W wire

Wa core wire

Detailed ways

Hereinafter, embodiments of the present invention will be described with reference to the drawings.

FIG. 1 is a perspective view showing a schematic configuration of a main part of an ultrasonic bonding apparatus according to an embodiment of the present invention. 2 is a perspective view showing the configuration of a terminal pressing member as a constituent member in the ultrasonic bonding apparatus, and FIG. 3 is a view showing the configuration of the terminal pressing member. 3( a ) is a front view, FIG. 3( b ) is a side view of a part shown using a cross section, and FIG. 3( c ) is an enlarged view taken along arrow IIIc in FIG. 3( a ). 4( a ) to 4 ( d ) are views for illustrating a process when terminals and electric wires are bonded to each other using an ultrasonic bonding device. 5( a ) is a plan view for identifying a portion of a terminal pressed by a terminal pressing member, and FIG. 5( b ) is a front view showing a state in which the terminal pressing member presses the terminal.

As shown in FIG. 1, the ultrasonic bonding apparatus according to the present embodiment has: an anvil 10 fixed at a predetermined position; an ultrasonic horn 20 installed above the anvil 10 so as to be vertically movable; and a terminal pressing The part 50, which has such a shape as to avoid interference with the ultrasonic horn 20, and is separately and independently installed from the ultrasonic horn 20 so as to be able to move vertically. The anvil 10, the ultrasonic horn 20, and the terminal pressing member 50 are all members made of metal.

In addition, although not shown, the ultrasonic bonding device also has: a vertical movement mechanism of the ultrasonic horn 20; a vibration mechanism for providing ultrasonic vibration to the ultrasonic horn 20; a vertical movement mechanism of the terminal pressing member 50; the transmission mechanism of the terminal 1; and the transmission mechanism of the electric wire W. In addition, the terminal-incorporated electric wire manufacturing apparatus including the ultrasonic bonding apparatus has a mechanism for exposing the core wire Wa by peeling off the insulating coating Wb of the end portion of the electric wire W.

Here, as shown in FIG. 4( a ), the terminal 1 has a prismatic mating terminal connection portion 2 (also referred to as a “box portion” in the case of a general female terminal) at the front for connection to a mating terminal. , and has a core wire Wa wire joint portion for joining to the end of the electric wire W continuous with the mating terminal connection portion at the rear.

In this case, the wire engaging portion 3 is configured to have a single flat plate, and is not equivalent to a bottom plate in a cylindrical wire engaging portion having a U-shaped cross section to be described later. The mating terminal connecting portion (box portion) 2 is molded in an angular cylindrical shape by joining or welding the joined portions of bent plate materials. The mating terminal connection portion 2 is configured such that the mating terminal is elastically interposed between the elastic contact piece and the inner surface of the outer peripheral wall of the mating terminal connection portion 2 . In this way, the mating terminal connection portion 2 can make electrical contact with the mating terminal.

In addition, the electric wire W is obtained in such a manner that a core wire Wa constituted by twisting a plurality of element wires into a circular cross section is externally covered with an insulating coating Wb made of synthetic resin, and the core wire Wa is passed to be joined to a terminal 1 The insulating coating Wb of the terminal is peeled off to expose a predetermined length required.

As shown in FIG. 1 , the anvil 10 is a block member in which the flat upper surface 11 a of the convex portion 11 having a width corresponding to the lateral width dimension of the wire engaging portion 3 of the terminal 1 serves as a wire engaging portion for the terminal 1 Part 3 placement surface.

The ultrasonic horn 20 is placed above the anvil 10 so as to be able to move vertically. While pressing from above the core wire Wa of the electric wire W placed on the wire joint portion 3 placed on the upper surface 11 a of the anvil 10 , the ultrasonic horn 20 passes the core wire Wa and the core wire Wa to the wire joint portion. The contact portion between 3 provides ultrasonic vibration, and the wire bonding portion 3 and the core wire Wa are bonded to each other.

When the ultrasonic horn 20 provides ultrasonic vibrations to the core wire Wa, the terminal pressing member 50 presses the wire joint portion 3 of the terminal 1 against the upper surface 11 a of the anvil 10 . As shown in FIGS. 1 to 3( c ), the terminal pressing member 50 is configured to function as a thick plate-like member having an upright posture. The terminal pressing member 50 is installed therein so as to have a posture in which the plate thickness direction is directed to the longitudinal direction of the terminal 1 . The shape of the lower half when viewed in the plate thickness direction is a laterally symmetrical shape that narrows as the shape goes toward the lower end.

A wide slit portion 52 starting from a position slightly more downward than the upper end and extending to the lower end is disposed at the center in the lateral width direction of the terminal pressing member 50 . The vertically extending slit portion 52 divides the lower half of the terminal pressing member 50 into laterally disposed leg portions 51 . In addition, as shown in FIG. 1 , the ultrasonic horn 20 is adapted to be vertically movable so as not to touch the terminal pressing member 50 in the slit portion 52 .

The guide wall 53 moves vertically along the lateral side surface of the protrusion 11 of the anvil 10 and faces each other in parallel. The portions 54 are disposed on upper sides of the guide walls 53, respectively.

The pressing step portion 54 provided in the laterally disposed leg portion 51 is a portion corresponding to the first pressing portion which is placed against the anvil 10 when the terminal pressing member 50 is lowered. The two end portions 3a are pressed in the width direction (the transverse width direction perpendicular to the longitudinal direction of the terminal 1) of the wire engaging portion 3 of the terminal 1 on the upper surface 11a of the convex portion 11 of the terminal 1 (refer to FIGS. 4(a) to 5( b)). These pressing step portions 54 include pressing surfaces 54 a slightly suspended on the upper surfaces of both lateral end portions of the wire engaging portion 3 .

Restricting walls 56 are respectively disposed on the upper sides of the pressing step wall portions 54 . The restriction wall 56 restricts the width of the wire joint portion 3 in the lateral width direction of the upper space to be narrower than the lateral width dimension of the wire joint portion 3, thereby restricting the core wire Wa so that when the core wire Wa is thermally softened by ultrasonic vibration And when deformed, the core wire Wa does not protrude beyond the width of the wire joint portion 3 . The restriction walls 56 vertically extend upward from the inner ends of the pressing surfaces 54 a of the pressing steps 54 , respectively.

In addition, these restricting walls 56 are wall surfaces that have a possibility that the core wire Wa closely adheres to the restricting walls 56 while the core wire Wa is pressed against the wall surface when deformed. Therefore, the wall surface of the restriction wall 56 has irregularities 56a even when the core wire Wa is attached thereto. The irregularity 56a extends to have a constant section in the vertical direction, and is adapted so that the core wire Wa is not caught by the irregularity 56a when the terminal pressing member 50 moves upward.

In addition, connecting bars 55 interconnecting the laterally disposed leg portions 51 are disposed at lower ends of the laterally disposed leg portions 51 . The connecting bar 55 is a portion corresponding to the second pressing portion, which is pressed against the anvil 10 and connected to the mat terminal connecting portion 2 on the side more forward than the portion for joining the core wire Wa to the wire coupling portion 3 part. The lower end surface 55 a of the connecting bar 55 pressed against the upper surface of the wire joint portion 3 is formed in a plane that is the same as that of the pressing surface 54 a of the pressing step portion 54 .

Therefore, as shown in FIGS. 5(a) and 5(b), when the terminal pressing member 50 moves downward, the pressing surface 54a and the connecting bar of the pressing step portion 54 disposed laterally are pressed against the upper surface of the wire engaging portion 3. There are three positions corresponding to each U-shaped side on the lower end surface 55 a of 55 , thereby pressing the wire engaging portion 3 against the anvil.

In addition, a heater 60 for heating the terminal pressing member 50 is incorporated into the terminal pressing member 50 . In this case, the feeder 60 is a rod-shaped cylinder, and is inserted into holes 61 drilled on both end surfaces in the lateral width direction of the terminal pressing member 50 . The position for disposing the heater 60 can be arbitrarily selected. The heater 60 may be arranged at any desired position of the terminal pressing member 50 , however, it is preferable to arrange the heater 60 at a position having a space for installation. The type of heater 60 may be selected arbitrarily. However, it is preferable to employ a type having a performance capable of rapidly increasing the temperature of the terminal pressing member 50 .

In addition to adding 60 thereof, a temperature sensor such as a thermocouple may be incorporated into the terminal pressing member 50 so that temperature control of the heater 60 is performed based on a measurement value of the temperature sensor. In addition, the heater 60 can be set to operate only in the initial stage when the plurality of terminals 1 and the electric wires E are engaged with each other.

Next, a process of bonding the terminal 1 and the electric wire W to each other by using the ultrasonic bonding apparatus having the above-mentioned configuration, and a bonding structure between the terminal 1 and the electric wire W obtained by this process will be described.

When the core wire Wa of the end portion of the electric wire W is bonded to the wire bonding portion 3 of the terminal 1 by using an ultrasonic bonding device, the wire bonding portion 3 of the terminal 1 is first placed on the anvil 10 as shown in FIG. on the upper surface 11a of the convex portion 11.

Thereafter, as shown in FIG. 4(b), the terminal pressing member 50 moves downward. Then, as indicated by arrow A, the pressing surface 54a of the pressing step portion (first pressing portion) 54 presses down both end portions 3a of the wire engaging portion 3 in the width direction, thereby pressing the wire engaging portion 3 against the anvil 10 . Simultaneously, the connection bar (second pressing portion) 55 presses down the portion connected to the mat terminal connection portion 2 on the side more forward than the portion for bonding the core wire Wa to the wire coupling portion 3, thereby abutting against the anvil. The seat 10 presses the wire joint portion 3 . In this state, the terminal 1 is detached from the carrier 9 (refer to FIG. 1 ) that connects the terminals 1 to each other in a linked shape.

At this time, as shown in FIG.

Thereafter, as shown in FIG. 4( c ), the core wire Wa of the end portion of the electric wire W is placed on the electric wire joint portion 3 . Then, in this state, as shown in FIG. 4( d ), as indicated by arrow B, the ultrasonic horn 20 moves downward and is located above the wire joint portion 3 . The core wire Wa placed on the wire joint portion 3 placed on the upper surface of the anvil 10 is pressed from above. While applying the pressing force, the ultrasonic horn 20 applies ultrasonic vibrations to the core wire Wa, and provides ultrasonic vibrations to the core wire Wa and the contact portion between the core wire Wa and the wire joint portion 3 . In this way, the wire joining portion 3 and the core wire Wa are joined to each other.

After engagement, the ultrasonic horn 20 moves upward first, and then the terminal pressing member 50 moves upward. The electric wire W bonded to the terminal 1 is lifted from the anvil 10 and transferred to the discharge unit. The above-described processing enables the bonding processing between the terminal and the electric wire to be completed at one time. This joining process is performed sequentially and automatically for each set of terminals 1 and electric wires W.

When the above-described processing is performed, at the stage of ultrasonic bonding, the terminal pressing member 50 presses against the anvil 10 both ends in the width direction of the wire engaging portion 3 of the terminal 1 and the inside of the wire engaging portion 3 is connected to the mating terminal connecting portion 2 parts. Therefore, it is possible to minimize the vibration following the wire joint portion 3 as much as possible. In particular, the connecting bar (second pressing portion) 55 of the terminal pressing member 50 presses against the anvil 10 the portion inside the wire engaging portion 3 connected to the mating terminal connecting portion 2 . Therefore, the vibration spreading to the side of the mating terminal connection portion 2 can be suppressed as much as possible. Accordingly, adverse effects caused by resonance of the mating terminal connection portion 2 can be eliminated, and thus, enhanced yield and improved quality of bonded products can be obtained using ultrasonic bonding.

In addition, the connection bar 55 is arranged on the front side of the core wire Wa of the end portion of the electric wire W. As shown in FIG. Therefore, positioning can be performed on the leading end of the core wire Wa, and thus, stable quality of a bonded product can be obtained. In addition, the restricting wall 56 of the terminal pressing member 50 restricts the core wire Wa so that the core wire Wa does not protrude when the core wire Wa is deformed. Therefore, the quality improvement of the joined finished product can be aimed at. In particular, the irregularity 56 a is disposed on the wall surface of the restriction wall 56 . Therefore, even when the core wire Wa is closely attached to the restriction wall 56 after the core wire Wa is softened and deformed, the restriction wall 56 and the core wire Wa can be prevented from adhering to each other. Therefore, operations can be performed smoothly and gradually.

In addition, the terminal pressing member 50 is heated by the heater 60 in an initial stage when the terminal pressing member 50 is cooled and especially production is started. In this way, it is possible to effectively prevent frictional heat from escaping from the bonding target portion to the terminal pressing member 50 . As a result, the fastening force between the terminal 1 and the core wire Wa can be increased, and the yield of electric wires incorporated into the terminal can be improved.

7 is an experimental result showing the difference in fastening force between the terminal 1 and the core wire Wa when the production of 10 manufactured electric wires incorporating terminals is started in the following states: the ambient temperature is 10° C., the ambient temperature is 10° C. is 40° C. and the ambient temperature is 10° C. and the terminal pressing member 50 is heated by the heater 60 . It is considered that the fastening force is more stable when the electric wire incorporating the terminal is produced in a state where the ambient temperature is 40° C., compared to a state where the ambient temperature is 10° C. Therefore, compared to when the electric wire incorporating the terminal is produced in the state where the ambient temperature is 10°C and the terminal pressing member 50 is heated by the heater 60, it can be considered that when the electric wire is produced in the state where the ambient temperature is 40°C Approximately the same results can be obtained with wires that have been inserted into the terminal. As described above, increasing the temperature of the terminal pressing member 50 can contribute to increased fastening force between the terminal 1 and the core wire Wa.

In addition, as shown in FIGS. 6( a ) and 6 ( b ), this bonding can obtain a bonding structure between the terminal and the electric wire. This joining structure is such that both end portions in the width direction orthogonal to the longitudinal direction of the wire joining portion 3 of the terminal are connected on the side more forward than the portion Wx for joining the core wire Wa to the wire joining portion 3 To the portion of the terminal connection portion 2, pressing spaces S11, S12, and S13 of the pressing member for pressing the wire bonding portion 3 against the anvil can be secured when the ultrasonic horn and the anvil are used for ultrasonic bonding. Therefore, since these spaces S11 to S13 are ensured, when the ultrasonic horn and the anvil are used for ultrasonic bonding, the wire bonding portion 3 can be reliably pressed against the anvil. Therefore, it is possible to prevent the vibration from spreading to the mating terminal connection portion 2 . As a result, adverse effects caused by resonance of the mating terminal connection portion 2 can be improved.

The present invention is not limited to the above-described embodiments, and can be appropriately modified and improved. In addition, the material, shape, size, number, and arrangement position of each constituent element in the above-described embodiment may be arbitrarily adopted without being limited to the above-described embodiment as long as the present invention can be realized.

For example, in the above-described embodiments, the case has been described where the wire engaging portion 3 of the terminal 1 is configured to have a single plane. However, as shown in FIG. 8( a ), the present invention is also applicable to a case where the wire engaging portion 103 provided at the rear of the terminal 101 having the mating terminal connection portion 102 at the front is configured in a cylindrical shape with a U-shaped cross section. Another embodiment of the present invention will be described by referring to FIGS. 8( a ) to 8 ( c ). The same reference numerals are given to the same constituent elements as those of the foregoing embodiment, and descriptions thereof are omitted. Hereinafter, only points different from the previously described embodiments will be described.

As shown in FIG. 8( a ), in this case, the wire bonding portion 103 of the terminal 101 has a core wire bonding portion 104 and a coating crimping portion 105 . The core wire bonding portion 104 and the coating crimping portion 105 are respectively configured to have: a common bottom plate 106 continuously extending from the mating terminal connection portion 102 ; and sides formed to stand upright on both sides in the width direction of the bottom plate 106 plates 107 and 108.

The ultrasonic bonding apparatus according to the present embodiment for bonding the electric wire W to the terminal 101 including the electric wire bonding portion 103 having the above-described shape is configured to bond the core wire Wa of the electric wire W to the bottom plate of the core wire bonding portion 104 by using ultrasonic bonding. 106.

That is, as shown in FIG. 8( b), the terminal pressing member 150 has a guide wall 153 that moves along the lateral side surface of the protrusion 11 of the anvil 10 when the terminal pressing member 150 moves downward, and The guide walls 153 are opposed to each other in parallel at the lower ends of the laterally disposed legs 151 . The terminal pressing member 150 has: a pressing stepped portion (first pressing portion) 154 abutting against the upper end of the laterally disposed side plate 107 of the core wire engaging portion 104 (corresponding to the and the connecting bar (second pressing portion) 155, which connects the laterally disposed leg portions 151 to each other, and presses against the anvil 10 against the bottom plate 106 on the The part of the mating terminal connection part 102 is connected to the side further forward than the part for joining the core wire Wa to the wire joint part 3 .

The pressing step portion 154 protrudes inward from the guide wall 153 by a dimension hanging on the upper end of the side plate 107 of the core wire engaging portion 104 , and enables the downward pressing surface 154 a to press the upper end of the side plate 107 . In addition, the lower surface 155a of the connection bar 155 is arranged to press the lower surface 155a against the upper surface of the bottom plate 106 at the position where the side plate 107 of the core wire connecting portion 104 is cut in the middle.

A case where the terminal 101 and the electric wire W are bonded to each other by using the ultrasonic bonding device constructed in this way will be described. As shown in FIG. 8( b ), the core wire engaging portion 104 of the terminal 101 is first placed on the upper surface 11 a of the convex portion 11 of the anvil 10 .

Thereafter, as shown in FIG. 8(c), the terminal pressing member 150 moves downward. Then, the pressing surface 154 a of the pressing step portion (first pressing portion) 154 presses down the upper ends of the side plates 107 at both ends in the width direction of the core wire engaging portion 104 , thereby pressing the core wire engaging portion 104 against the anvil 10 . Simultaneously, the connection bar (second pressing portion) 155 presses against the anvil 10 to connect the mating terminal connection portion on the bottom plate 106 on the side more forward than the portion for bonding the core wire Wa to the wire joint portion 3 102, thereby pressing the core wire engaging portion 103 against the anvil 10.

Thereafter, the core wire Wa of the end portion of the electric wire W is placed on the bottom plate 106 of the core wire joint portion 104 . Then, in this state, the ultrasonic horn 20 moves downward and over the bottom plate 106, thereby pressing the core wire placed on the bottom plate 106 of the core wire joint portion 104 placed on the upper surface of the anvil 10 from above. Wa. Further, the ultrasonic horn 20 applies ultrasonic vibrations to the core wire Wa while applying a pressing force, and provides ultrasonic vibrations to the core wire Wa and a contact portion between the core wire Wa and the core wire bonding portion 104 . In this way, the core wire joining portion 104 and the core wire Wa are joined to each other.

During the above process, the terminal pressing member 150 presses against the anvil 10 both end portions in the width direction of the wire engaging portion 103 of the terminal 101 , and a portion of the wire engaging portion 103 connected to the mating terminal connecting portion 102 on the bottom plate 106 . Therefore, it is possible to minimize the vibration following the wire joint portion 103 as much as possible. In particular, the connecting bar (second pressing portion) 155 of the terminal pressing member 150 presses against the anvil 10 the portion inside the wire engaging portion 103 connected to the mating terminal connecting portion 102 . Therefore, it is possible to prevent the vibration from spreading to the mating terminal connection portion 102 as much as possible. Accordingly, adverse effects caused by resonance of the mating terminal connection portion 102 can be eliminated, and thus, enhanced yield enhancement and improved quality of bonded products can be obtained using ultrasonic bonding.

In addition, the connection bar 55 is arranged on the front side of the core wire Wa of the end portion of the electric wire W. As shown in FIG. Therefore, positioning of the leading end of the core wire Wa can be performed, and thus, stable quality of a spliced product can be realized. In addition, in this case, the core wire bonding portion 104 of the terminal 101 has a side plate 107 that restricts the core wire Wa in advance so as not to protrude when the core wire Wa is deformed. Therefore, improved quality of the bonded product can be obtained.

In addition, the terminal pressing member 150 is heated by the heater 60 at an initial stage when the terminal pressing member 150 is cooled and in particular, production is started. In this way, it is possible to effectively prevent frictional heat from escaping from the bonding target portion to the terminal pressing member 150 . As a result, the fastening force between the terminal 101 and the core wire Wa can be increased, and the yield of the electric wire incorporating the terminal can be improved.

A heater may be incorporated into the anvil 10 in advance to heat the anvil 10 .

Here, the above-mentioned embodiments of the ultrasonic bonding device according to the present invention will be briefly summarized and respectively listed in the following [1] and [2].

[1] An ultrasonic bonding device comprising:

An anvil (10), (10) comprising an upper surface for placing a wire engaging portion (3) of a terminal (1) comprising a mating terminal connection portion (2) at the front for connection to a mating terminal ), and has at its rear a wire engaging portion for engaging the core wire (Wa) at the end of the electric wire (W), the wire engaging portion;

An ultrasonic horn (20) placed above the anvil and configured to pass through the core wire and the core wire while pressing the core wire placed on the wire joint portion placed on the upper surface of the anvil from above. The connection part with the wire joint part provides ultrasonic vibration, so that the wire joint part and the core wire are bonded to each other;

a terminal pressing member (150) configured to press the wire joint portion against the upper surface of the anvil when ultrasonic vibration is provided by the ultrasonic horn; and

The heater (60) heats the terminal pressing part.

[2] In the ultrasonic bonding apparatus according to the above [1], the heater is disposed in the terminal pressing member.

The present invention has been described in detail with reference to specific embodiments. However, it is obvious to those skilled in the art that the present invention can be changed or modified without departing from the spirit and scope of the present invention.

This application is based on and claims priority from Japanese Patent Application No. 2012-283568 filed on December 26, 2012, the entire contents of which are hereby incorporated by reference.

Industrial Applicability

According to the present invention, it is possible to effectively prevent frictional heat that contributes to bonding from escaping by increasing the temperature of the terminal pressing member. As a result, it is possible to increase the fastening force between the terminal and the core wire from the initial stage when production is started. The present invention provides these advantageous effects and is useful in the field of ultrasonic bonding in which terminals and electric wires are bonded using ultrasonic bonding.

Claims (2)

1. a ultrasonic bonding equipment, comprising:

Anvil block, comprises the upper surface of the wire joint portion for accommodating terminal, and this terminal comprises the coupling terminal connection part for being connected to coupling terminal in front portion, and has the wire joint portion of the heart yearn of the end for joining electric wire at its rear portion;

Ultrasonic variable amplitude bar, be placed in above described anvil block, and be configured to: while be placed on the described heart yearn on the described wire joint portion that the described upper surface of described anvil block is placed from top pressing, by providing ultrasonic vibration to described heart yearn and the connecting portion between described heart yearn and described wire joint portion, and described wire joint portion is engaged each other with described heart yearn;

Terminal pressing component, is configured to: when utilizing described ultrasonic variable amplitude bar to provide described ultrasonic vibration, and the described upper surface against described anvil block presses described wire joint portion; And

Heater, heats described terminal pressing component.

2. ultrasonic bonding equipment according to claim 1,

Wherein, described heater is placed in described terminal pressing component.