JP2916581B2 - Automatic fusible joining device and wire shaping device - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an automatic joining apparatus and a wire shaping apparatus for a fusible body, and more particularly to an automatic joining apparatus and a wire shaping apparatus suitable for joining a low melting point fuse wire to a high melting point lead frame. Related to the device.

[0002]

2. Description of the Related Art FIG. 13 shows a conventional thermal fuse (JP-A-7-169381). This fuse is used for communication. 1 is a fusible alloy such as solder (hereinafter referred to as a fuse wire), 2 is a cylindrical body made of an insulator, and 3 is a lid-shaped terminal. In this fuse, the fuse wire 1 is connected to the cylinder 2
The two ends are projected diagonally inside, and both ends are projected to the outside of the cylinder 2 and bent along the outer wall surface. The fuse wire 1 is sandwiched between the outer wall surface of the terminal 3 and the inner wall surface of the terminal 3 to be connected to the terminal 3 or hot air is blown toward the solder previously disposed near the end of the fuse wire 1. ,
The end of the fuse wire 1 was soldered to the terminal 3 with hot air.

As for a fuse wire having a relatively large diameter, a bonding method and apparatus disclosed in Japanese Patent Application Laid-Open No. 7-328780 are known. In this bonding method and apparatus, the fuse wire and the lead member are brought into contact with each other, and the contact portion is irradiated with a laser beam. The member is heated by a laser beam, and the contact portion is gradually cooled and hardened while being heated at a low temperature by heat conduction from the lead member.

According to this method, the contact portion is not quenched, so that cracking and embrittlement can be prevented. Also, at the moment when the contact portion is heated and the fuse wire is melted, the lead member is moved by a predetermined distance. Pushing it to the side has the advantage of improving the bonding strength because the so-called thinning of the bonding portion is prevented.

[0005]

However, in the above-mentioned conventional joining methods, the fuse lines are previously cut to a predetermined length, so that the handling is complicated and unsuitable for automation. In particular, in the former joining method, it is necessary to bend the end portion of the fuse wire and hook it on the outer wall of the cylindrical body, so that it takes time to assemble the fuse, and there is a problem that the workability is reduced. In addition, since the inside becomes invisible when the terminal is covered with the cylindrical body, it is not known whether the insertion of the fuse wire between the cylindrical body and the terminal is good, and if it is uncertain, the quality of the fuse is not constant, and furthermore, When the terminal is covered, tension is applied to the fuse wire, so that the wire diameter of the fuse wire may be reduced or the wire may be broken, thus causing a problem that reliability is further reduced. In particular, in the case of a very small device such as a micro fuse, such inconvenience is likely to occur and the failure rate is high.

On the other hand, the latter joining method and apparatus can be applied only to a relatively thick fuse line because the fuse line is gripped by a clamp. In addition, since the laser beam irradiation port is moved to the lead member side, and both ends of the fuse wire are sequentially irradiated and heated, there is a problem that workability is low and productivity is low.

SUMMARY OF THE INVENTION The present invention has been made to solve the above-mentioned conventional problems, and an object of the present invention is to provide an automatic joining apparatus and a wire shaping apparatus for a fusible material which improve workability and stabilize quality. Is to provide.

[0008]

According to a first aspect of the present invention, there is provided an automatic fusible member joining apparatus, comprising: a loader for moving a magazine containing a lead frame up and down; and one lead frame from the loader. A first transporting device that takes out and transports the wire to a joining station; a wire feeder that feeds a wire to a lead portion of the lead frame; and a wire that cuts the supplied wire into a predetermined length and shapes the wire into a predetermined shape. A wire shaping device for bringing a cut end into contact with a lead portion of a frame, a laser irradiating device for irradiating a laser beam from a back surface of the lead portion and joining an end portion of the wire to the lead portion, and the wire material is joined; And a second transport device for transporting the lead frame taken out of the joining station. According to a second aspect of the present invention, in the first aspect, each end of the cut wire is simultaneously joined to two opposing leads of the lead frame by two laser beams. According to a third invention, in the first or second invention, the wire is a fuse wire made of a material having a lower melting point than the lead frame. Further, the wire shaping device according to the fourth invention is a punching hole penetrating through upper and lower surfaces,
A lower die having a wire rod through-hole penetrating perpendicular to the side wall on the short side of the punch hole, and a lead frame transport path formed on the upper surface so as to be perpendicular to the long side of the punch hole; Suction means for sucking a wire introduced into the wire through-hole, a punch fitted in the punch hole so as to be able to move up and down and having a cutting edge at an upper edge of the wire introduction side, and guiding a laser beam to a lead portion of a lead frame. An upper die that has a conical laser beam irradiation hole and presses the lead of the lead frame against the end of the wire, and presses the wire against the punch to shape the wire into a predetermined shape. And Further, the wire shaping device according to the fifth invention is characterized in that the punch hole penetrates the upper and lower surfaces, the wire rod through hole penetrates orthogonally to the short side wall of the punch hole, and the punch hole is formed on the upper surface. A lower die having a lead frame transport path formed so as to be orthogonal to the long side, suction means for sucking a wire introduced into the wire through-hole, and a wire inserted and lifted up and down in the punch hole A punch having a cutting edge at an upper end edge on an introduction side, and a conical laser beam irradiation hole for guiding a laser beam to a lead portion of a lead frame, wherein the lead portion of the lead frame is pressed against an end of the wire and the wire is pressed. Is pressed against the punch to form a predetermined shape, a vertically movable upper die, a proximity sensor attached to a fixing member of the punch so as to face a reference surface provided on the lower die, and an output signal of the proximity sensor. Characterized in that a lifting controlling means for controlling the rise stroke of the punch based on.

In the first invention, the lead frame is transported from the magazine in the loader to the joining station by the first transport device, and the wire material is supplied to the lead portion of the lead frame by the wire material supply device and cut into a predetermined length. Since the end portion of the wire is joined to the lead portion of the lead frame by the laser irradiation device, the lead frame is transported by the second transport device and stored in the magazine in the unloader, so that the welding of the wire is automated. Can be. In addition, the lead portion of the lead frame is irradiated from the side opposite to the wire with a laser beam, and the joint of the wire is heated and melted by heat conduction from the heated lead frame. Optimal joining can be performed regardless of the wire diameter of the wire rod by adjusting the laser beam irradiation time or laser power without being overheated. Further, rapid cooling of the joint is prevented, so that cracking and embrittlement can be prevented. Furthermore, since the wire is cut into a predetermined length by the wire shaping device and shaped into a predetermined shape so that the cut end abuts on the lead portion of the lead frame, tension is not applied to the wire and the wire diameter is reduced. There is no thinning or disconnection.

In the second invention, the two laser beams simultaneously irradiate two opposing leads of the lead frame and simultaneously join the ends of the wire, so that the joining time can be reduced.

In the third aspect, the wire is a fuse wire made of a material having a lower melting point than the lead frame, and is melted by heat transfer when the lead frame is heated.

[0012] In the fourth aspect of the present invention, the punch is raised to cut a wire guided into the lower punch hole into a predetermined length by a cutting blade. The upper die presses the cut wire against a lead frame and a punch to shape it into a predetermined shape.
Therefore, no tension is applied to the wire material, and the wire diameter does not become thin and the wire is not broken.

In the fifth invention, the distance from the reference surface of the lower die to the proximity sensor changes according to the rising stroke of the punch. This rising stroke differs depending on the wire diameter of the wire, and is controlled by the lifting control means,
Enables the use of wires with various wire diameters. In addition, by setting the distance between the upper die and the lower die according to the wire diameter, a pressure of a predetermined amount or more is not applied to the wire, so that the wire does not become thin or break.

[0014]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Hereinafter, the present invention will be described in detail based on one embodiment shown in the drawings. FIG. 1 is a front view of an automatic joining apparatus according to an embodiment of the present invention, in which a front cover is omitted, FIG. 2 is a plan view of the interior of the automatic joining apparatus, and FIG. FIG. 4 is a plan view of the lead frame to which the fuse wires are joined. In the present embodiment, the fusible wire is a fuse wire 1 having a low melting point (300 ° C.), and this fuse wire 1 is replaced with a lead frame 5 made of a material having a high melting point (1450 ° C.).
An example of joining to the substrate will be described. The fuse wire 1 has a wire diameter of 46 μm to 120 μm. The lead frame 5 is made of a 42 alloy (iron,
As shown in FIG. 4, the surface of the land portion 5 a formed of a nickel alloy (nickel alloy) and to which the fuse wire 1 is bonded is silver-plated in advance to enable the bonding of the fuse wire 1. In the lead frame 5, perforations 6 are formed on both side edges 5b in the longitudinal direction, and a connecting portion 5c for connecting the both side edges 5b to a center portion in the width direction, and a front end facing the land portion 5a. Is formed, and the connecting portion 5c and the fuse piece 5d are separated by the slit 8. When used as a fuse, the fuse small piece 5d is cut and separated along the cutting line 7 from the side edge 5b to form a terminal portion.

The schematic structure of the automatic joining apparatus 11 will be described with reference to FIGS.
, A loader 14, a first transport device 15, a wire feeder 16, a wire shaping device 17, and a second transporter which are disposed above and inside the housing 12 in association with each other. The apparatus 18 includes a device 18, a laser irradiation device 19, an unloader 20, and a control circuit (not shown) disposed below the inside of the housing 12 and controlling the device 11 itself. In FIG. 1, the illustration of the wire feeder 16 is omitted, and FIG.
, The illustration of the loader 14 is omitted.

The front of the housing 12 is open, and the front opening 21 is covered by a front cover (not shown) which can be opened and closed in the vertical direction. Openings are also provided in the left and right side plates of the housing 12, respectively, and these openings are covered by a side cover 22 that can be opened and closed.

The loader 14 is movable up and down along a guide rail 24, and is loaded with a cassette 25 for accommodating the lead frame 5 at a predetermined interval in the height direction before the fuse wire 1 is joined. The frame 5 is configured to be intermittently raised at the predetermined interval by the drive motor 26 when the frame 5 is supplied. The rotation of the drive motor 26 is controlled by the loader 1 via a rotation transmission mechanism such as a chain or a gear.
4 is transmitted.

The wire shaping device 17 cuts the fuse wire 1 supplied from the wire feeding device 16 to the joining station S to a predetermined length, shapes the fuse wire 1 into a predetermined shape, and cuts the fuse wire 1 into the lead portion 5a of the lead frame 5. The end portions are configured to abut. The wire supply device 16 is installed in front of the wire shaping device 17, intermittently sends out the fuse wires 1, and supplies the fuse wires 1 to the joining station S. The first transfer device 15 that transfers the lead frame 5 in the cassette 25 to the joining station S is disposed between the wire shaping device 17 and the loader 14. The first transport device 15 includes a sprocket 30 that engages with a perforation 6 (see FIG. 4) provided on the lead frame 5 and a drive motor 31 that rotates the sprocket 30 intermittently in the lead frame feed direction.
And a chain 32 for transmitting the rotation of the drive motor 31 to the sprocket 30.

The second transfer device 18 and the unloader 20 are arranged on the opposite side of the wire feeder 16 from the loader 14 and the first transfer device 15 side, that is, on the left side in FIG. . In addition, the wire supply device 16 that supplies the fuse wire 1 to the joining station S is provided in front of the joining station S, and the wire feeding device 16 is located above the joining station S.
The laser irradiating device 19 for irradiating the lead portion 5a of the lead frame 5 installed with the laser beam and joining the fuse wire 1 to the lead portion 5a is provided.

The second transfer device 18 is a first transfer device 1
5, the sprocket 35 and the drive motor 36
And the chain 37 and the like, and transports the lead frame 5 from which the fuse 1 has been joined to the unloader 20 from the joining station S. The unloader 20 has the same structure as the loader 14, is arranged movably up and down along a guide 40, and is an empty cassette for accommodating the lead frames 5 to which the fuse wires 1 are joined at predetermined intervals in the height direction. 2
When the lead frame 5 is loaded and the lead frame 5 is stored, it is configured to be intermittently lowered at the predetermined interval by the drive motor 41. The loader 14, the first transfer device 15, the second transfer device 18, and the unloader 20 are the same as those generally used widely in semiconductor manufacturing equipment and the like. Is omitted.

Next, the wire supply device 16 and the wire shaping device 1
The configuration of the laser irradiation device 7 and the laser irradiation device 19 will be described in detail with reference to FIGS. FIG. 5 is a side view showing a part of the wire feeder cut away, FIG. 6 is a sectional view of a tension applying means, FIG. 7 is a side sectional view of a wire shaping apparatus, FIG. 8 is a sectional view of a lower die and an upper die, 9 is a plan view of the lower mold, FIG. 10 is a sectional view of the lower mold, and FIG.
1 is a cross-sectional view taken along the line XI-XI in FIG. 9, and FIG. 12 is a cross-sectional view showing a state where the fuse wire is joined to the lead frame. In FIG. 5, the wire supply device 16 includes a case 51 installed above the front end of a horizontal base 50 that is long in the front-rear direction. Inside the case 51 is a fuse wire 1
, A drive motor 53 for intermittently rotating the spool 52 and sending out the fuse wire 1, and a nozzle for blowing compressed air 55 to the fuse wire 1 immediately after being drawn from the spool 52. 54
A rotatable roller 56 for guiding the fuse wire 1,
A tension regulating member 58 provided between the roller 56 and the spool 52 for regulating the tension of the fuse wire 1 and a sensor 59 for detecting the fuse wire 1 are provided.

The nozzle 54 blows compressed air 55 onto the fuse wire 1 from above, thereby giving slack as shown by a solid line in FIG. 5 to prevent the fuse wire 1 from breaking. That is, the fuse wire 1 has a wire diameter of 46 μm to 12 μm.
Since it is extremely thin, about 0 μm, it breaks with a slight force. Therefore, when supplying the fuse wire 1 to the wire shaping device 17, it is necessary to prevent the portion between the spool 52 and the roller 56 from being tensioned. In this case, if the slack is given by a mechanical means, an external force will be applied to the fuse wire 1 as a result, and there is a possibility that the fuse wire 1 is disconnected. However, if air pressure is used, the fuse wire 1 can be loosened without contact. Therefore, there is no disconnection.

The roller 56 is disposed close to the inside of a wire outlet 57 provided at the lower part of the back plate constituting the case 51.

The tension restricting member 58 has a groove into which the fuse wire 1 is inserted by branching the lower end into a forked shape, whereby the right and left direction of the fuse wire 1 (a direction perpendicular to the paper surface). Swing and upward movement.

The sensor 59 is preferably a proximity switch using a magnetic field such as a high-frequency oscillation type or a differential coil, and is disposed between the roller 56 and the tension regulating member 58. The fuse wire 1 immediately after being pulled out from the spool 52 is held in a relaxed state as shown by a solid line in FIG. In this state, the sensor 59 cannot detect the fuse wire 1, and when the fuse wire 1 is supplied to the wire shaping device 17 by a predetermined amount (length), the fuse wire 1 ′ portion between the spool 52 and the roller 56 becomes As shown by a two-dot chain line, the sensor 59 is detected by the sensor 59 because the user enters a region where the sensor 59 can be detected by tension. When the sensor 59 detects the fuse wire 1, the drive motor 53 is driven by a drive signal from the control unit based on the detection signal, whereby the spool 52 is intermittently rotated,
The fuse wire 1 is extended by a predetermined amount.

At the rear end of the upper surface of the base 50, two clamps 60A and 60B for holding the fuse line 1 substantially horizontally at a predetermined interval, and a fuse line 1 provided before and after these clamps, respectively. 2 to give tension to
Two tension applying means 61A and 61B are provided. The clamps 60A and 60B are alternately opened and closed by the solenoid 62, and at the same time, one of the clamps 60A and 60B is reciprocated to grip the fuse wire 1 and intermittently feed the fuse wire 1 by a fixed amount. In this case, of the two clamps 60A and 60B, for example, the clamp 60A located forward is the base 5
Fixed to 0. On the other hand, the clamp 60B located rearward is provided movably in the front-rear direction along the guide rail 63. When the fuse wire 1 is gripped, the clamp 60B is moved forward by a predetermined distance along the guide rail 63 by the drive motor 64, so that the fuse The wire 1 is sent to the wire shaping device 17. At this time, the front clamp 60A is held in the open state, and does not hold the fuse wire 1. When the fuse wire 1 is fed, the clamp 60B is opened to release the gripping state of the fuse wire 1, and is returned to the original front position by the reverse rotation of the drive motor 64. At this time, the clamp 60 </ b> A on the front side is closed to hold the fuse wire 1. As described above, the clamps 60A and 60B alternately open and close, and the clamp 60B reciprocates, whereby the fuse wire 1 can be intermittently fed into the wire shaping device 17 by a fixed amount.

The tension applying means 61A, 61B
Is a main body 7 having a through hole 71 through which the fuse wire 1 passes as shown in FIG.
A predetermined tension can be applied to the fuse wire 1 by supplying compressed air from the air supply hole 72 to the through hole 71 and discharging the compressed air from one of the openings. Further, the main body 70 is provided with a switching lever 73 for switching the direction of discharging the compressed air and switching the direction of the tension applied to the fuse wire 1. In this case, the tension applying means 61A disposed in front of the fixed-side clamp 60A ejects the compressed air supplied to the through-hole 71 toward the front side, that is, toward the case 51, whereby
A tension in a direction to retract the fuse wire 1 is given,
Conversely, the tension applying means 61B disposed behind the movable clamp 60B applies a tension in a direction in which the fuse wire 1 is advanced.

Next, the configuration of the wire shaping device 17 will be described with reference to FIGS.
This will be described in detail with reference to FIG. In these figures, the wire shaping device 17 includes a lower die 81 fixed to a support 80. A plate 82 that forms a transport path for the lead frame 5 is fixed to the upper surface of the lower die 81 together with a guide plate, which will be described later. The center of the upper surface of the plate 82 joins the fuse wire 1 to the land portion 5 a of the lead frame 5. Part, namely the joining station S. In the center of the plate 82, a slit-shaped punch hole 83 extending in the front-rear direction is formed through the upper and lower surfaces, and the lower end of the punch hole 83 is formed through the lower die 81 through the upper and lower surfaces. In communication with the through hole 84. The length of the punch hole 83 is substantially equal to the length of the fuse wire 1 joined to the lead frame 5, and the width is substantially equal to the diameter of the fuse wire 1. The upper end of the communication hole 84 has the same length as the punch hole 83, and the lower end is formed longer.

On the upper surface of the plate 82, two guide plates 86a and 86b are fixed in parallel at a predetermined interval in the front-rear direction, and a groove formed by both the guide plates and the upper surface of the plate 82 is formed. A lead frame transport path 87 is formed. The transport-side end of the lead frame transport path 87 is tapered so as to facilitate the entry of the lead frame 5. In the center of the upper surface of the plate 82, two holes are provided on both sides of the pinch hole 83, respectively.
A total of four holes 88 are formed one by one, and push-up pins 89 are fitted into these holes 88 so as to be prevented from coming out upward and to be able to come and go. This push-up pin 8
Numeral 9 is for preventing the lead frame 5 from being in close contact with the plate 82. As shown in FIG.
The upper end is slightly protruded from the upper surface of the plate 82 by being constantly urged upward by zero. Further, at the center in the width direction of the upper surface of the plate 82, a fuse wire escape groove 91 for preventing contact between the fuse wire 1 and the plate 82 is formed over the entire length. However, it is not limited to the entire length, and may be formed only on the downstream side of the punch hole 83.

Further, a fuse line guide member 93 is fixed to the front surface of the plate 82. As shown in FIGS. 8 and 9, the fuse wire guide member 93 is composed of two members 93a and 93b which are divided into right and left parts and are joined to each other, and are fed from the wire feeder 16 to the joint surface of one member 93a. The fuse wire 1 is connected to the punch hole 8.
A wire rod through hole 92 leading to 3 is formed. This wire rod through-hole 92 penetrates orthogonally to the upstream side wall on the short side of the punch hole 83.

In the inside of the plate 82, the axis coincides with the wire rod through hole 92, the front end of the plate 82 communicates with the short side of the punch hole 83 on the upstream side wall, and the rear end opens at the rear end of the lower surface of the plate 82. A fuse wire suction hole 96 (see FIG. 10) is formed. The fuse wire suction holes 96 are
It is connected to a vacuum pump 98 via an exhaust hole 97 formed in the lower die 81. When the air in the punch hole 83 is exhausted and depressurized through the exhaust hole 97 and the fuse wire suction hole 96 by the driving of the vacuum pump 98, the fuse wire 1 guided into the punch hole 83 becomes a fuse wire suction hole. Since it is sucked by 96, it keeps a horizontal state.

The punch 100 for cutting the fuse wire 1 to a predetermined length is slidably inserted in the through hole 84 of the lower die 81 and the punch hole 83 of the plate 80 in a vertical direction. The punch 100 is made of a thin metal plate made of cemented carbide, the width of the upper end is slightly smaller than the length of the punch hole 83, and the upper edge of the wire introduction side is the fuse wire 1
Of the cutting blade 101 (FIG. 12). A concave portion 102 for forming the fuse wire 1 into a predetermined shape is formed at the center of the upper surface of the punch 100. The recess 102 is an arc-shaped recess.

Referring to FIG. 7 and FIG.
0 protrudes below the lower die 81, and the lifting means 105
It is configured to be raised and lowered. Punch 10
A motor is used as the lifting / lowering means 105 for rotating the punch 100 through the screw body 106.
Is transmitted to the holder 107.
The holder 107 holds the bearing 10 on the guide support 108.
9 and is mounted so as to be vertically movable and prevented from rotating.

The lower surface of the lower die 81 facing the holder 107 forms a reference surface 110, and the proximity sensor 112 which is in close proximity to the reference surface 110 is
7 is provided on the upper surface. This proximity sensor 112
A distance to the reference surface 110, in other words, a rising stroke of the punch 100 is detected, and control means (not shown) controls the motor 105 based on the detection signal. When the proximity sensor 112 is provided and the motor 105 is controlled by the control means, various types of fuse wires 1 having different wire diameters can be used. That is, when the wire diameter of the fuse wire 1 is large, it is necessary to increase the rising stroke in order to surely cut the fuse wire 1 by the punch 100, and conversely, when the wire diameter is small, it is necessary to reduce the rising stroke. Therefore, a rising stroke according to the diameter of the fuse wire 1 is preset in the control means, and when the detection value of the proximity sensor 112 matches the set rising stroke, the driving of the motor 105 is stopped. It is possible to secure a rising stroke according to the diameter of the fuse wire.

Above the lower die 81, an air cylinder 1
An upper mold 120 that is raised and lowered by 21 is provided.
The upper die 120 is fixed to the lower surface of the die set 122, and an arc-shaped projection 123 (see FIG. 12) is integrally provided at the center of the lower surface in correspondence with the concave portion 102 of the punch 100. A pin 125 (see FIG. 8) for positioning the lead frame 5 conveyed onto the joining station S is protruded. Further, the upper die 120 is provided with two laser beam irradiations which guide the laser beam 126 from the laser irradiating device 19 to the upper surface of each land portion 5a of the lead frame 5 before and after the protrusion 123. A hole 127 is formed through the upper and lower surfaces. These laser beam irradiation holes 127 are formed in a conical shape whose diameter decreases downward. The laser beam irradiation holes 127 are also provided in the die set 122.
Is formed to penetrate. The die set 122 is provided with the guide post 10.
8 is attached via a bearing 131 so as to be movable up and down, and is driven by the air cylinder 121. Such an upper mold 120 is provided with a die set 122 when the fuse wire 1 is joined.
As a result, the lead frame 5 on the joining station S is pressed against the plate 82 of the lower die 81, and when the joining of the fuse wires 1 is completed, the lead frame 5 is raised to release the pressed state of the lead frame 5. The lowering stroke of the upper die 120 depends on the wire diameter of the fuse wire 1.
Is adjusted at the same time when the rising stroke of the control means is preset in the control means.

As the laser irradiation device 19, for example, a YAG laser is used, and the laser irradiation device 19 is disposed downward above the upper die 120. The reason for dividing the laser beam 126 from the laser irradiation device 19 into two beams is that the two land portions 5a and 5
This is because the respective ends of the fuse wire 1 are simultaneously welded to a. The two laser beams 126 have the same beam intensity, are separated into two, and are shaped into a desired beam diameter.
The two opposite land portions 5a, 5a of the lead frame 5 are passed through the laser beam irradiation holes 127 from above.
In other words, heating is performed by irradiating from the side opposite to the fuse line 1 for a predetermined time (about 1.5 sec or less). Thereby, each end 1a of the fuse wire 1 is heated and melted by heat conduction from the heated lead frame 5, and the
Can be joined to the land portion 5a. If the beam intensity of the laser beam 126 is adjusted so that the heating temperature at this time is about 20 ° C. higher than the melting temperature of the fuse wire 1, the lead frame 5 itself does not melt.

After each end 1a of the fuse wire 1 is melted, it is gradually cooled and hardened to thereby form a land 5a.
Joined to. After the joining of the fuse wires 1 is completed, the punch 100 is lowered to return to the initial position, and at the same time, the upper die 120 is raised and returned to move the lead frame 5 by the pitch of the land portion 5a to be welded next. The land is guided to the punch hole 83. Thereafter, the fuse lines 1 can be automatically and continuously joined by repeating the same steps as described above. As a means for splitting the laser beam 126 emitted from one laser irradiation device 19 into two beams, an optical element such as a half mirror or a prism may be used (for example, Japanese Patent Application Laid-Open No. 8-294790).
No.).

As described above, the automatic joining apparatus 11 according to the present invention.
According to this, since the fuse line 1 and the lead frame 5 can be automatically supplied to the joining station S, the joining of the fuse line 1 can be automated, and the productivity can be improved. Further, according to the present invention, since the two end portions 1a of the fuse wire 1 are simultaneously joined by the two laser beams 126, the joining time can be shortened, and the productivity can be further improved. Furthermore, each end 1 of the fuse wire 1
a is indirectly and simultaneously heated and melted through the lead frame 5 and joined together, so that overheating of the fuse wire 1 is prevented, rapid cooling of the joint is suppressed, and the joint of the fuse wire 1 is joined. Cracking and embrittlement can be prevented. In particular, if the end portion 1a of the fuse wire 1 is not melted, the spread when the end portion 1a is melted is small, and good and optimal joining can be performed. Further, since no tension is applied to the fuse wire 1 at the time of joining, a fuse having a small variation in rated capacity can be manufactured without a decrease in wire diameter or disconnection.

Further, a proximity sensor 112 is provided on the fixing member of the punch 100 in proximity to the reference surface 110 of the lower die 81,
Since the rising stroke of the punch 100 is regulated by the control means in accordance with the detection signal of the sensor 112, pressure can be applied according to the wire diameter even if the fuse wires have different wire diameters. Can be cut into Therefore, the wire diameter of the fuse wire 1 does not become thin and does not break, and the rated capacity of the fuse does not vary.

In the above embodiment, an example was shown in which the fuse wire 1 was used as a fusible member and the fuse wire 1 was joined to the lead frame 5. However, the present invention is not limited to this, and the present invention is not limited to this. A copper wire may be used as the wire. The fusible material is not limited to a wire, but may be a ribbon.

[0041]

As described above, the automatic fusible body joining apparatus according to the present invention transports a wire and a lead frame to a joining station by a carrier, and cuts the wire into a predetermined length by a wire shaping apparatus. Since the bonding is performed to the land portion of the lead frame, automation of the bonding and improvement in productivity can be achieved. In addition, since the wires are joined without applying tension, the quality can be kept constant without reducing the wire diameter or breaking the wires. In addition, since the land portion of the lead frame is irradiated and heated by the laser beam from the side opposite to the wire, the wire is not overheated, just adjusting the laser beam irradiation time or laser power, Optimal joining can be performed regardless of the wire diameter of the wire. Further, rapid cooling of the joint is prevented, so that cracking and embrittlement can be prevented.

In the present invention, the two lands of the lead frame facing each other are simultaneously irradiated by the two laser beams to perform the joining, so that the joining time can be shortened, which is suitable for mass production.

In the present invention, the distance to the lower reference plane is detected by the proximity sensor, and the control means controls the lifting / lowering means of the punch based on the detection signal. It is possible to join various kinds of wire rods having different wire diameters with one type of mold without using an upper die and a lower die corresponding to each wire diameter, thereby improving the versatility of the apparatus.

[Brief description of the drawings]

FIG. 1 is a front view of an automatic joining apparatus according to an embodiment of the present invention, with a front cover removed.

FIG. 2 is a plan view showing the inside of a housing of the automatic joining apparatus.

FIG. 3 is a side sectional view of the automatic joining apparatus.

FIG. 4 is a plan view of the lead frame to which the fuse lines are joined.

FIG. 5 is a side view showing a part of the wire rod supply device cut away.

FIG. 6 is a cross-sectional view of the tension applying means.

FIG. 7 is a side sectional view of the wire shaping device.

FIG. 8 is a sectional view of a lower mold and an upper mold.

FIG. 9 is a plan view of a lower die.

FIG. 10 is a sectional view of a lower mold.

FIG. 11 is a sectional view taken along line XI-XI in FIG. 9;

FIG. 12 is a cross-sectional view showing a state where a fuse wire is joined to a lead frame.

FIG. 13 is a schematic configuration diagram of a conventional fuse.

[Explanation of symbols]

DESCRIPTION OF SYMBOLS 1 ... Fuse wire, 1a ... End part, 5 ... Lead frame, 5
a: Land portion, 11: Automatic joining device, 12: Housing, 14
... loader, 15: first transfer device, 16: wire rod supply device,
17: Wire rod shaping device, 17: Second transport device, 19: Laser irradiation device, 20: Unloader, 25: Magazine, 61
A, 61B ... tension applying means, 81 ... lower mold, 83 ...
Punch hole, 87: lead frame transport path, 92: wire through hole, 98: vacuum pump, 100: punch, 101 ...
Cutting blade, 105: drive motor, 110: reference plane, 112:
Proximity sensor, 120: upper mold, 126: laser beam, 1
27: Laser irradiation hole, S: Joining station.

──────────────────────────────────────────────────続 き Continuation of the front page (56) References JP-A-61-214321 (JP, A) JP-A-63-258717 (JP, A) JP-A-3-24345 (JP, U) (58) Survey Field (Int.Cl. ⁶ , DB name) H01H 69/02 B23K 26/00

Claims (5)

(57) [Claims] 1. A loader for lifting and lowering a magazine containing a lead frame, a first transport device for removing lead frames one by one from the loader and transporting the lead frame to a joining station; and a wire rod for supplying a wire to a lead portion of the lead frame. A supply device, a wire shaping device that cuts the supplied wire into a predetermined length, shapes the wire into a predetermined shape, and abuts a cut end on a lead portion of the lead frame, and a laser beam from a back surface of the lead portion. A laser irradiation device that irradiates the end portion of the wire to the lead portion by irradiating the lead frame; and a second transport device that removes the lead frame to which the wire is bonded from the bonding station and transports the lead frame. Automatic joining equipment for fusible materials. 2. The apparatus for automatically joining fusible bodies according to claim 1, wherein each end of the cut wire is simultaneously joined to two opposing leads of a lead frame by two laser beams. Automatic joining equipment for fusible materials. 3. The automatic fusible body joining apparatus according to claim 1, wherein the wire is a fuse wire made of a material having a lower melting point than the lead frame. 4. A punch hole penetrating through the upper and lower surfaces, a wire through-hole penetrating perpendicularly to a short side wall of the punch hole,
And a lower die having a lead frame transport path formed on the upper surface so as to be orthogonal to a long side of the punch hole, a suction unit for sucking a wire introduced into the wire through hole, and an inside of the punch hole. A punch having a cutting edge at the upper end edge of the wire introduction side and a conical laser beam irradiation hole for guiding a laser beam to a lead portion of a lead frame; And an upper die that can be lifted and lowered so as to press the wire against the punch while pressing the wire against the end of the wire. 5. A punch hole penetrating through the upper and lower surfaces, a wire through hole penetrating at right angles to a short side wall of the punch hole,
And a lower die having a lead frame transport path formed on the upper surface so as to be orthogonal to a long side of the punch hole, a suction unit for sucking a wire introduced into the wire through hole, and an inside of the punch hole. A punch having a cutting edge at the upper end edge of the wire introduction side and a conical laser beam irradiation hole for guiding a laser beam to a lead portion of a lead frame; An upper die that can be lifted and lowered to press the wire against the punch while shaping it into a predetermined shape, and a proximity sensor attached to a fixing member of the punch so as to face a reference surface provided on the lower die. An elevating control means for controlling an ascending stroke of the punch based on an output signal of the proximity sensor.