JP6675885B2 - Terminal, cable joined body having the terminal, joining method - Google Patents

Description

The present invention relates to a terminal, a cable joined body having the terminal, and a joining method .

  BACKGROUND ART Conventionally, there is known an ultrasonic bonding method in which a conductor portion of an electric wire and a terminal are sandwiched between a horn and an anvil and vibrated while applying a load to join the conductor portion of the electric wire and the terminal. reference.).

JP 2012-192413 A

  However, in ultrasonic bonding, the conductor and the terminal of the electric wire were sandwiched between the horn and the anvil and vibrated while applying a load, so that these parts were joined. If so, the vibration energy oscillated from the horn is dispersed, and the joining efficiency is poor.

  The present invention provides a terminal having improved joining efficiency and a cable joined body having the terminal.

In order to solve the above object, the present invention has the following configuration.
That is, the present invention according to claim 1 is a terminal having a plate-shaped joint portion that is ultrasonically joined to a cable with a coating, and an electric contact portion to which a mating terminal is connected, and the electric contact portion and the electric contact portion. An intervening portion provided between the joining portion and the connecting portion to make them continuous, wherein the joining portion is provided with a plurality of minute protrusions on an opposing surface facing the cable, and the intervening portion has A terminal that is provided with a locking portion that is locked to an anvil mounted when ultrasonic bonding is performed, and is positioned for positioning the anvil in a longitudinal direction .

Invention described in claim 2 is the invention according to claim 1, before Kikan portion, notch portion is provided to suppress heat transfer from the junction to the electrical contact portion It is characterized by having been done.

According to a third aspect of the present invention, there is provided a cable with a coating, and the terminal according to the first or second aspect , wherein the small projection pierces a coating portion of the cable with the coating, and the cable is provided with the coating. A cable joined body which is solid-phase joined to a cable conductor.

According to a fourth aspect of the present invention, there is provided a joining method for ultrasonically joining the terminal according to the first or second aspect to a cable with a coating by using an anvil having a tip and a locking receiving portion. A joining method in which a locking portion is locked to the locking receiving portion, and the terminal is positioned in a longitudinal direction of the anvil .

  According to the first aspect of the present invention, a plurality of minute projections are provided on the joint surface of the terminal that is ultrasonically joined to the coated cable on the facing surface facing the cable. The covered cable and the terminal are provided with the covered cable superimposed on the opposing surface of the terminal and, in a state where these are pressurized, vibrated in an orthogonal direction orthogonal to the overlapping direction, but provided on the opposing surface of the terminal. Since the plurality of minute projections abut on the covering portion of the covered cable, the covering portion is efficiently removed. Furthermore, in the process of ultrasonically joining the terminal after the coating is removed and the conductor of the cable with the coating, since the minute projections of the terminal are in contact with the conductor of the cable with the coating, the ultrasonic bonding is performed. The stress exerted by the vibration energy is intensively transmitted to the minute projections. Therefore, the joining efficiency can be improved.

Further , the joining portion is provided with an engaging portion which is engaged with an anvil mounted when ultrasonic joining is performed. Therefore, by locking the locking portion provided at the joint portion of the terminal to the anvil, relative movement between the terminal and the anvil due to vibration during ultrasonic bonding is suppressed, and the vibration is covered. It is efficiently transmitted to cables and terminals. Therefore, the joining efficiency can be further improved.

According to the invention as set forth in claim 2 , an electric contact portion connected to the counterpart terminal, and an interposition portion provided between the electric contact portion and the joining portion to connect them are provided, Is provided with a notch for suppressing heat transfer from the joint to the electrical contact. That is, since the notch is provided in the space, escape of heat generated at the joint is suppressed, and heat required for metal bonding during ultrasonic bonding is secured. As described above, the escape of the heat amount from the joining portion is suppressed, so that a decrease in the joining efficiency can be suppressed even in the configuration having the electric contact portion.

According to a third aspect of the present invention, there is provided a cable with a coating, comprising the cable with a coating and the terminal according to the first or second aspect , wherein the minute projections penetrate the coating of the cable with the coating. Solid-phase bonded to a conductor. In such a cable joined body, at the time of ultrasonic joining, since the minute projections break through the covering and are solid-phase joined to the conductor of the covered cable, the operation of removing the covering portion in advance is unnecessary. Thereby, it is possible to improve the working efficiency when manufacturing the cable joined body.

It is a perspective view showing a terminal concerning one embodiment of the present invention, and a cable joined body having the terminal. 2A and 2B are diagrams illustrating the terminal illustrated in FIG. 1, wherein FIG. 1A is a perspective view, FIG. 1B is a top view, and FIG. 1C is a side view. FIG. 2 is a perspective view illustrating a state in which the cable joined body illustrated in FIG. 1 is manufactured. FIG. 4 is a diagram showing a side view of FIG. 3. It is a side view which shows the state in which the terminal and the cable with coating were installed in the ultrasonic bonding apparatus. (A) is a figure which shows a mode that the horn which comprises an ultrasonic bonding apparatus approaches an anvil, (B) is a figure which shows the state in which operation | movement advanced further than (A), (C) is FIG. 9 is a diagram showing a state in which the operation is further advanced than in FIG. FIG. 2 is a perspective view showing a partial cross section of the cable joined body shown in FIG. 1.

  Hereinafter, a terminal according to an embodiment of the present invention will be described with reference to FIGS. In the ultrasonic bonding apparatus 30 shown in FIGS. 3 and 4, the conductor 20 and the terminal fitting 1 of a flexible flat cable (hereinafter, referred to as FFC) 2 as a covered cable are electrically and mechanically connected. Is manufactured. That is, the cable joined body 10 has the FFC 2 and the terminal fitting 1, and these are ultrasonically joined and electrically and mechanically connected.

  The FFC 2 is configured to have a plurality of strip-shaped conductor portions 20A, as shown in FIGS. Each conductor portion 20A is connected to each terminal fitting 1. Each conductor portion 20 </ b> A includes a conductor 20 and a covering portion 21 that covers the conductor 20. Each conductor 20 is made of a metal that is more easily plastically deformed than the terminal fitting 1. The covering portion 21 is configured to have a pair of insulating sheets 21A and 21B, and each of the insulating sheets 21A and 21B is made of an insulating synthetic resin and formed in a strip shape. The pair of insulating sheets 21A and 21B are configured with each conductor 20 interposed therebetween.

  As shown in FIG. 1 and FIG. 2, the terminal fitting 1 has a plate-shaped FFC connection portion 11 (joining portion) to which each conductor 20 of the FFC 2 is connected and an electric contact connected to a mating terminal (not shown). It has a portion 12 and an interposition portion 13 provided between the FFC connection portion 11 and the electric contact portion 12 to make them continuous. Such terminal fittings 1 are provided side by side on a straight line in the order of the FFC connection part 11, the space part 13, and the electrical contact part 12. The FFC connection part 11 is formed in a substantially plate shape, and the facing surface 11a facing the FFC 2 is formed in a rectangular shape.

  In the following, the direction in which the FFC connection portion 11, the space portion 13, and the electrical contact portion 12 are arranged, and the direction along the arranged direction among the opposing surfaces 11a of the FFC connection portion 11, is referred to as "longitudinal direction Y". Of the opposing surfaces 11a of the FFC connection portion 11, a direction perpendicular to the longitudinal direction Y may be referred to as "width direction X", and a direction perpendicular to the longitudinal direction Y and the width direction X may be referred to as "height direction Z". is there.

  As shown in FIG. 2, the terminal fitting 1 is formed such that the width dimensions of the FFC connection portion 11, the space portion 13, and the electrical contact portion 12 are substantially constant. The FFC connection portion 11 and the space portion 13 are formed to have substantially the same plate thickness dimension (dimension in the height direction Z) from one end to the other end in the longitudinal direction Y.

  The FFC connection portion 11 has a plurality of minute projections 14 on an opposing surface 11a opposing the FFC 2. Each of the minute projections 14 is obtained by performing press working on the facing surface 11a facing the FFC 2. Such a minute projection 14 is solid-phase bonded to the conductor 20 of the FFC 2 in a state where the FFC 2 and the terminal fitting 1 are ultrasonically bonded to form the cable bonded body 10.

  As shown in FIG. 4, each microprojection 14 has a cross-sectional shape that does not have a corner (marked with R) and that has a cross-sectional shape whose cross-sectional area gradually decreases toward the top 14 a. It is formed to have a shape. Further, it is desirable that each minute projection 14 is provided at a position facing the knurl projection 34 of the horn 31 constituting the ultrasonic bonding apparatus 30. That is, as shown in FIG. 4, in the cross section in the longitudinal direction Y (the vibration direction of the horn 31), the dimension L between the tops 14a of the adjacent minute projections 14 and the dimension between the centers P of the adjacent knurl projections 34. L is formed so as to be substantially equal.

  Here, if the groove depth between the minute protrusions 14 adjacent in the longitudinal direction Y is larger than a predetermined dimension, the FFC 2 curves and cuts into the groove between the minute protrusions 14 during ultrasonic bonding, and There is a concern that the projection 14 may hinder the movement of the horn 31. For this reason, each minute projection 14 is formed so as to have a protruding dimension that does not hinder the movement of the horn 31.

  In the present embodiment, the plurality of microprojections 14 are formed so as to have a mountain shape in which the cross-sectional area gradually decreases toward the top 14a, but the cross-sectional area from the opposing surface 11a to the tip end is small. It may be formed so as to have a substantially columnar or prismatic shape.

  As shown in FIG. 2, the electric contact portion 12 is formed in a hollow prismatic shape into which a counterpart terminal can be inserted.

  As shown in FIG. 2, the gap 13 is provided with a pair of cutouts 15 at both ends in the width direction X. The pair of cutouts 15 are formed by cutting both ends of the space 13 in the width direction X into a rectangular shape. By forming the notch 15 in the space 13 in this manner, the cross-sectional area of a portion continuous from the FFC connection portion 11 to the electric contact portion 12 is reduced, so that the amount of heat generated in the FFC connection portion 11 is released. Is suppressed, the amount of heat required for metal bonding at the time of ultrasonic bonding is secured, and a reduction in bonding efficiency is suppressed.

  In addition, the locking portion 16 that locks to the anvil 33 of the ultrasonic bonding device 30 is provided in the gap 13. The locking portion 16 is formed so as to have a convex shape protruding toward the anvil 33 from a surface of the FFC connection portion 11 opposite to the facing surface 11a. In the present embodiment, the locking portion 16 is formed by press working.

  Next, an ultrasonic bonding apparatus 30 for ultrasonically bonding the FFC 2 and the terminal fitting 1 will be described. As shown in FIGS. 3 to 5, the ultrasonic bonding apparatus 30 has a horn 31 on which a piezoelectric vibrator (not shown) as a drive source is mounted, a chip 32 mounted on the horn 31, and a chip 32. Anvil 33 (one of a pair of molds). The piezoelectric vibrator vibrates ultrasonically when supplied with AC power. A chip 32 is attached to the horn 31 to which the piezoelectric vibrator is attached. Therefore, the piezoelectric vibrator causes the chip 32 to vibrate via the horn 31 or the like. At this time, the vibration direction (longitudinal direction Y) of the tip 32 is orthogonal to the approaching / separating direction (height direction Z) in which the tip 32 and the anvil 33 approach / separate (relative) to each other.

  The tip 32 has a plurality of knurl protrusions 34 protruding toward the anvil 33. The knurl protrusion 34 is provided in a truncated quadrangular pyramid shape. The plurality of knurl protrusions 34 are arranged in a grid along the longitudinal direction Y (vibration direction) and the width direction X of the FFC connection portion 11. The plurality of knurl protrusions 34 are all provided in the same size and the same shape. In the present embodiment, two knurl protrusions 34 are arranged side by side in the width direction X.

  The anvil 33 is provided with a rectangular installation surface 33 a on which the terminal fitting 1 is installed, at a position facing the chip 32. The installation surface 33a is formed such that the FFC connection portion 11, the interval portion 13, and a part of the electrical contact portion 12 of the terminal fitting 1 can be installed. The installation surface 33 a is provided with a concave portion 35 as a lock receiving portion into which the locking portion 16 of the terminal fitting 1 fits, and a groove-shaped portion 36 for suppressing movement of the terminal fitting 1. As shown in FIG. 5, the concave portion 35 is provided at a position facing the locking portion 16 when the FFC connection portion 11 is installed at a predetermined position on the installation surface 33 a, and the groove-shaped portion 36 is provided on the terminal fitting 1. It is provided at a position where the FFC connection unit 11 is installed. Thus, in a state where the FFC connection portion 11 is installed at a predetermined position on the installation surface 33 a, the engagement portion 16 of the terminal fitting 1 is fitted into the concave portion 35 of the anvil 33, so that the terminal fitting 1 is engaged with the anvil 33. You. As described above, when the ultrasonic bonding is performed, the locking portion 16 provided on the FFC connection portion 11 of the terminal fitting 1 is locked to the anvil 33 so that the terminal 1 can be connected to the anvil 33 in the longitudinal direction Y. The terminal 1 is positioned on the anvil 33 so that the top portion 14a of the minute projection 14 is positioned so as to face the center P of the knurl projection 34 in the direction of contact and separation (height direction Z) between the chip 32 and the anvil 33. Will be installed. Furthermore, the relative movement between the terminal fitting 1 and the anvil 33 due to vibration during ultrasonic bonding is suppressed by locking to the anvil 33, and the vibration is efficiently transmitted to the FFC 2 and the terminal fitting 1. .

  The groove-shaped portion 36 is formed by a plurality of grooves formed in the width direction X and arranged in the vibration direction (longitudinal direction Y). Each groove is formed so as to be concave from the installation surface 33a. That is, the bottom of each groove is formed so as to be located farther from the chip 32 in the contacting / separating direction (the height direction Z) than the installation surface 33a.

  Next, an ultrasonic bonding method using the ultrasonic bonding apparatus 30 having the above-described configuration will be described. First, as shown in FIG. 6A, the locking portion 16 of the terminal fitting 1 is brought closer to the concave portion 35 of the anvil 33. The locking portion 16 is locked in the concave portion 35, and the FFC connection portion 11 is set on the setting surface 33 a of the anvil 33. At this time, the knurl protrusion 34 of the chip 32 is located at a position aligned with the minute protrusion 14 of the FFC connection portion 11 in the contact / separation direction (height direction Z).

  As described above, by locking the locking portion 16 of the terminal fitting 1 to the concave portion 35 of the anvil 33, when the terminal fitting 1 and the FFC 2 are ultrasonically bonded, the terminal due to the vibration at the time of ultrasonic bonding. The relative movement between the fitting 1 and the anvil 33 is suppressed, and the vibration is efficiently transmitted to the FFC 2 and the terminal fitting 1. In FIGS. 6A, 6B, and 6C, the groove portion 36 is omitted.

  The terminal fitting 1 is installed such that the longitudinal direction Y of the FFC connection portion 11 is along the vibration direction. Thus, the terminal fitting 1 is installed on the anvil 33 so as not to be movable.

  Next, the conductor portion 20A of the FFC 2 is overlapped on the opposing surface 11a where the minute protrusion 14 is present in the FFC connection portion 11, and the FFC 2 and the terminal fitting 1 are positioned between the chip 32 and the anvil 33.

  Thereafter, as shown in FIG. 6B, the chip 32 is moved closer to the anvil 33 and comes into contact with the upper coating 21A of the conductor 20A. Further, the chip 32 is further approached, and the conductor portion 20A is pressed against the FFC connection portion 11. In this state, the piezoelectric vibrator is vibrated. The vibration is transmitted to the tip 32 via the horn 31. When the chip 32 vibrates, the vibration vibrates the chip 32 and the conductor portion 20A. At this time, since the minute protrusion 14 of the terminal 1 is in contact with the lower coating 21B of the conductor portion 20A, the movement of the chip 32 due to vibration between the lower coating 21B and the fine projection 14 is suppressed. The vibration is transmitted to the upper coating 21A in a concentrated manner. Thus, the upper coating 21A is melted by the vibration energy and frictional heat generated between the upper coating 21A and the chip 32. Since the chip 32 is pressed against the conductor portion 20A, the molten upper coating 21A is removed from between the conductor 20 and the FFC connection portion 11 sandwiched between the chip 32 and the anvil 33, and the knurl protrusion of the chip 32 is formed. A point-like mark 23 (shown in FIG. 7) having substantially the same shape as 34 is formed, and the tip 32 is brought closer to the anvil 33.

  Thereafter, the chip 32 contacts the conductor 20 of the conductor portion 20A. Since the minute protrusion 14 of the terminal 1 is in contact with the lower coating 21B of the conductor portion 20A, the movement of the chip 32 caused by the vibration of the chip 32 between the lower coating 21B and the minute projection 14 is suppressed. The vibration is transmitted to the conductor 20 in a concentrated manner. Thus, the lower coating 21B is melted by the vibration energy and the frictional heat generated between the conductor 20 and the chip 32. Since the chip 32 is pressed against the conductor portion 20A, the molten lower coating 21B is removed from between the conductor 20 and the FFC connection portion 11 sandwiched between the chip 32 and the anvil 33.

  Thereafter, as shown in FIG. 6C, the conductor 20 is pressed against the FFC connection portion 11 of the terminal 1. At this time, since the micro projections 14 of the terminal 1 are in contact with the conductor 20 of the conductor portion 20A and the chip 32 is in contact with the conductor 20, stress due to vibration energy from the further chip 32 is concentrated on the micro projections 14. 7, the oxide film of the microprojections 14 and a part of the conductor 20 in contact with the microprojections 14 is destroyed, a new surface appears, and the microprojections 14 of the terminal fitting 1 and the conductor 20 are solid-phase bonded (solid-phase bonding portion 10a, shown in FIG. 7). ). In this way, as shown in FIG. 7, the cable joined body 10 in which the terminal fitting 1 and each conductor portion 20A of the FFC 2 are ultrasonically joined is completed.

  As shown in FIG. 7, in such a cable joined body 10, at a position facing the knurl protrusion 34 (a position where the solid-phase joint 10 a is formed), the covering portion 21 is removed, and the solid-phase joint 10 a Are joined together. Further, the covering portions 21 on both sides in the vibration direction (longitudinal direction Y) of the solid-phase bonded portion 10a are not removed. As described above, in the longitudinal direction Y of the terminal fitting 1, the covering portion 21 at the position where the solid-phase joining portion 10a is formed is removed, and the covering portions 21 on both sides in the longitudinal direction Y of the solid-phase joining portion 10a are removed. The absence state is expressed as “a state in which the minute projection 14 has broken through the covering portion 21 of the FFC 2”. Thus, as shown in the figure, the terminal fitting 1 is solid-phase bonded to the conductor 20 of the FFC 2 in a state where the minute projections 14 have pierced the covering portion 21 of the FFC 2.

  In the above-described embodiment, the locking portion 16 provided on the terminal fitting 1 and locked to the anvil 33 is formed by pressing, but the present invention is not limited to this. The locking portion 16 may be formed so as to have a convex shape by cutting and raising the space 13.

  Further, in the present embodiment, the pair of notches 15 are provided at both ends in the width direction X in the space 13, but the present invention is not limited to this. The pair of cutouts 15 may be cutout so as to reduce the thickness (height) of the space 13. That is, the pair of notches 15 only need to be formed so that the cross-sectional area of a portion continuous from the FFC connection portion 11 to the electric contact portion 12 is reduced, and the notch portions 15 need not be a pair.

  In the present embodiment, the terminal fitting 1 is described as an example of the terminal, but the present invention is not limited to this. The terminal may be a bus bar or a conductive sheet continuous with the pattern of the circuit board.

  Further, in the present embodiment, the FFC2 has been described as an example of the coated cable, but the present invention is not limited to this. An electric wire having a round cross section may be used as the covered cable.

  The above-described embodiment merely shows a typical mode of the present invention, and the present invention is not limited to the embodiment. That is, those skilled in the art can make various modifications in accordance with conventionally known knowledge without departing from the gist of the present invention. Of course, as long as the terminal and the cable assembly of the present invention are provided with the configuration according to the modification, they are included in the scope of the present invention.

1 Terminal fittings (terminals)
10 Cable joint 2 FFC (Cable with coating)
11 FFC connection (junction)
11a Opposing surface 12 Electric contact portion 13 Intermediate portion 14 Small protrusion 15 Notch portion 16 Locking portion 20 Conductor 21 Covering portion

Claims (4)

A terminal having a plate-shaped joint that is ultrasonically joined to the coated cable,
An electrical contact portion to which a mating terminal is connected;
An intervening portion provided between the electrical contact portion and the joining portion to make them continuous,
The joining portion is provided with a plurality of minute projections on a facing surface facing the cable ,
A terminal, characterized in that the terminal portion is provided with a locking portion that locks to an anvil mounted when ultrasonic bonding is performed, and is used for positioning the anvil in a longitudinal direction . The front Kikan portion, the terminal according to claim 1, characterized in that notch in order to suppress heat transfer to the electrical contact portion from the joining portion. A sheathed cable;
And the terminal according to claim 1 or 2 ,
A cable joined body characterized in that the minute projections are solid-phase joined to a conductor of the covered cable in a state where the minute projections penetrate a covering portion of the covered cable. A bonding method for ultrasonically bonding the terminal according to claim 1 or 2 to a covered cable using a chip and an anvil having a lock receiving portion,
The joining method, wherein the locking portion is locked to the locking receiving portion, and the terminal is positioned in a longitudinal direction of the anvil.

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