JPH0159072B2 - - Google Patents

Description

[Detailed description of the invention] Technical field of invention The present invention relates to an automatic soldering device.

Conventional Problems In general, lead frames for integrated circuits (ICs) are mainly made of copper, but they also contain large amounts of iron, nickel, and other elements, making it difficult for solder to adhere to them. Therefore, in the preliminary soldering line for attaching the solder film to the lead frame, a water-soluble chlorine-based flux is used during soldering to remove the metal oxide film (rust) on the surface of the lead frame. This makes it easier for the solder to adhere to the lead frame. However, if the above-mentioned chlorine-based flux remains on the lead frame, IC chip, etc. after soldering, the lead frame, IC chip, etc. may be corroded by the action of chlorine.

In contrast, conventional automatic soldering equipment does not completely remove the flux remaining on ICs after soldering, and improvements to automatic soldering lines are desired.

Purpose of the Invention The present invention has been made in view of the above points.
The present invention aims to provide a line configuration that can completely remove water-soluble flux adhering to objects to be soldered in an automatic soldering line.

Structure of the Invention The automatic soldering apparatus of the present invention includes a fluxing unit, a preheating unit, a soldering unit, and an air bubbling tank below the conveyor, along a conveyor that conveys objects to be soldered. In addition, a hot water washing unit and a plurality of cold water washing units each formed by providing a shower above the conveyor, and a drying means formed by a rotary air blow unit, a heating unit, and a cooling fan unit are sequentially provided. It is something.

Embodiments of the Invention The present invention will now be described with reference to illustrative embodiments.

As shown in FIG. 1, along a conveyor 1 that conveys soldering objects, there are a soldering object intake section 2, a fluxing unit 3 consisting of a jet flux tank containing water-soluble chlorine flux, and an air fluxing unit 3. An air knife 4 consisting of a blowing nozzle removes excess flux, a preheating unit 5 consisting of a heater, a soldering unit 6 consisting of a jet soldering bath, and a hot water of approximately 80°C to clean residual flux from objects to be soldered. A hot water cleaning unit 7 for removing flux, three cold water cleaning units 8, 9, and 10 for cleaning and removing residual flux from objects to be soldered with cold water of approximately 15°C, drying means 11, and a part for taking out objects to be soldered. 12 are arranged in sequence.

The drying means 11 is formed by two sets of rotary air blow units 13, two sets of heating units 14 each consisting of a heater, and two sets of cooling fan units 15.

The conveyor 1 has a soldering object intake section 2.
The hood 16 covers almost the entire circumference, except for the take-out part 12, to prevent gases generated from flux and solder from escaping into the room, and the gases are discharged outside through a duct 17.

The conveyor 1, each unit, and other members described above are made of stainless steel or coated with acid-resistant paint.

Further, as shown in FIGS. 2 and 3, a hot water cleaning unit 7 and a cold water cleaning unit 8,
9 and 10 are formed by providing an air bubbling water tank 20 below the conveyor 1 and providing a shower 21 above the conveyor 1.

The air bubbling water tank 20 is installed inside an outer tank 22 and has air blowing nozzles 23 at two locations on the bottom. It rises and hits objects to be soldered below the water surface. At this time, the hot water 24 or cooling 2 in the water tank 20
Together with the bubbles 26, 5 also becomes a high-speed upward flow and violently collides with the objects to be soldered, etc., and together with the disturbance effect of the bubbles 26, it effectively removes the water-soluble chlorine-based flux attached to the objects to be soldered. It can be washed off. Further, the shower 21 is configured, for example, as shown in the figure, with water fountain holes provided at three locations on the lower surface of two rows of pipes.

Further, as shown in FIG. 3, the conveyor 1 is
A frame-shaped transport holder 29 and an inner endless rail 31 that supports the wheels 30 of this transport holder 29.
and an endless rail 32 on the outer peripheral side and an endless chain 33 for conveyance arranged along the endless rail 31 on the inner peripheral side, and the endless chain 33 for conveyance moves between a pair of guide rails 34 and , conveyance pins 35 are provided upwardly protruding at predetermined intervals, and the movement of the pins 35 is made smooth by bearings 36 fitted to the pins 35, and the pins 35 are provided protruding from one side of the conveyance holder 29. It is inserted into the engaged plate 37 so as to be vertically movable. The endless rails 31 and 32 on both sides are covered by removable waterproof covers 38 and waterproof sheets 39 on both sides.

Further, as shown in FIG. 4, the rotary air blow unit 13 has four support rods located above and below from the middle section inside the tank 42.
The upper and lower rotary joints 45 are supported by the upper and lower support rods 43 via the support plate 44, and the upper and lower rotary joints 45 support the upper and lower rotary joints 45 by means of the upper and lower rotary joints 45. The rotating hollow shaft 47 of the rotating pipe 46 and the upper and lower air supply pipes 48 are connected, and the air nozzle 4 is connected to the upper and lower rotating pipe 46 slightly diagonally rearward with respect to the rotation direction.
9 is installed protrudingly. These upper and lower air nozzles 49 rotate the rotating pipe 46 by the reaction of the air jet while blowing out air, and while rotating, the air jet blows out water droplets attached to the transport holder 29, the objects to be soldered, etc. Fly. The direction of rotation is set to be reversed vertically. The tank 42 is sealed with a transparent vinyl chloride plate 51 or the like, except for the drain port 50 at the bottom. 52 is a waterproof sheet. Note that the air supply pipe 48 and the rotating hollow shaft 47 of the turning pipe 46 may be integrated, and the air supply pipe 48 may be forcibly rotated.

Further, as shown in FIGS. 5 to 8, a jig 55 for aligning and supporting objects to be soldered is inserted into the transport holder 29 from above and engaged therein. This jig 55 includes a frame body 57 made of titanium that is attached to support parts 56 on both sides of the transport holder 29, and a frame body 57 made of titanium.
As shown in FIG. 9, a plurality of sets of 2 are provided across the lower parts of the 2 to support the lower side of the main body of an integrated circuit (hereinafter referred to as IC) 58 as an object to be soldered.
One set of tungsten lower steel wire 59 and IC
Each set of lower steel wires 59 along both sides of the main body of 58
A set of two upper steel wires 60 made of tungsten are arranged parallel to the upper part of the frame body 57 and have one end fixed to the frame body 57.
and a gate body 61 that supports the other end of each set of upper steel wires 60 and is movable up and down with respect to the frame body 57.
and an IC insertion opening 62, which is opened in the frame body 57 and faces the gate body 61, and serves as an insertion opening for an object to be soldered. The gate body 61 is
Both ends of the frame body 57 are vertically movably supported by recesses 64 of guide plates 63 provided on the inner side surfaces of both sides of the frame body 57, and four upper and A stopper pin 65 located approximately at the center of the lower steel wires 59, 60 is provided to protrude and lock the IC 58 at one end. Handle portions 66 are provided on the upper surface of both sides of the frame body 57. Note that the ends of the upper and lower steel wires 59 and 60 on the pin 65 side are connected to the frame 57.
Insert it, fold it back at the outer surface of the frame 57, and attach the presser plate 67.
If the pin 65 is also inserted into the frame 57 from the outside and the flange portion at the outer end is pressed from the outside by the presser plate 67, the frame can be easily fixed to the frame 57. It can be attached to 57. I C
The lead frame 68 of 58 protrudes downward from between the upper steel wire 60 and the lower steel wire 59, as shown in FIG.

Also, as shown in FIG. 10, the package 7
A large number of IC5s are arranged and housed in series inside 1.
8 is attached to the soldering object alignment and support jig 55 by the soldering object transfer device 72 shown in FIGS. 11 to 13.

This soldering object transfer device 72 has a pair of support plates 76 on top of a support base 75 having a stopper 73 and a shock absorber 74.
The intermediate portion of the tilting plate 78 is rotatably supported via a support shaft 77 rotatably supported by the support shaft 7.
7. The main body of the rotary actuator 79 is fixed to the support plate 76 so that the rotary actuator 79 rotates by being connected to the rotation axis, and one side and the other side of the tilting plate 78 are connected to the rotation axis of the rotary actuator 79.
The tilting plate 7 is used as a fulcrum to move up and down.
On the upper surface of the right side of FIG. 8 in FIG. A package fixing means is provided, and an intermediate guide 82 and a mounting guide 83 are provided on the upper surface of the left side of the tilting plate 78 in FIG.

As shown in FIGS. 13 and 14, the installation guide body 83 has a plurality of inverted convex guide grooves 86 formed coaxially with the multiple rows of packages 71 on the upper surface, and the middle part of the guide grooves 86 The lead frame 68 of the IC 58 is slid on the stepped portion 87 provided at the step 87, and the soldering object support positioned between the lead frames 68 of the IC 58 in the jig 55 for aligning and supporting the soldering object is slid below the step 87. The lower steel wire 59 as a member is inserted and arranged. A jig positioning portion 88 is provided around the mounting guide 83, and the 11th
Push-up pins 89 are provided protruding from both sides of the right end in the figure, and the push-up pins 89 push up the gate body 61 of the jig 55 for aligning and supporting objects to be soldered. Further, a cover body 90 is provided above the right half of the mounting guide 83 in FIG. 1, and this cover body 90 prevents the IC 58 from jumping out from the guide groove 86. This cover body 90 has a knob 9
1 allows rotation around the support shaft 92.

As shown in FIGS. 15 and 16, the intermediate guide body 82 has a plurality of guide protrusions 96 formed coaxially with multiple rows of packages 71 in a recess 95 on the upper surface. IC58 is placed on 96 so as to straddle it and is slid. Intermediate guide body 82
A cover body 97 is fixed over the entire surface of the upper side. The lower surface of the cover body 97 is provided with guide grooves 98 facing each of the guide protrusions 96.
Further, guide rods 99 are erected from both sides of the intermediate guide body 82 near the mounting guide body 83, and both ends of the gate actuating body 100 are fitted into the guide rods 99 on both sides so as to be able to move up and down. A gate pin 101 is provided to protrude from the body 100 through the cover body 97 to each guide protrusion 96. Gate operating body 10
0 is biased downward by the spring 102 and, if necessary, lifts the handle 103 to retreat each gate pin 101 from the guide concave portion 98. Similarly, guide rods 104 are erected from both sides of the intermediate guide body 82 near the package 71,
A stopper operating body 105 is attached to the guide rod 104 on both sides.
A stopper pin 106 is fitted from the stopper actuating body 105 to the cover body 97 so as to be movable up and down. This stopper pin 106 has a locking portion 107 at its upper end engaged with the upper surface of the stopper operating body 105, and a flange portion 109 is attached downward by a spring 108 fitted inside the stopper operating body 105 and the cover body 97. By pressing, the lower end portion protrudes into the guide groove portion 98. The stopper actuating body 105 is urged downward by a spring 110, and the handle 11 is urged as necessary.
1 to pull up each stopper pin 106 from the guide groove 98.

The reason why the gate pin 101 and the stopper pin 106 are provided so that they can move up and down is that
This is to divide the IC row into two equal parts so that it can be continuously supplied to the jig 55 twice, but it is also possible to divide it into three or more equal parts with a simple design change.

Next, to explain the transfer of the IC 58 from the package 71 to the jig 55 for aligning and supporting soldered objects, the tilting plate 78 is set in a downward position to the right as shown by the two-dot chain line in FIG. , this tilting plate 78
Place the lower recess 112 on one side of the positioning pin 113.
Multiple rows of IC-containing packages 71 are aligned in parallel, both ends of which are pressed and fixed by a fixing bar 80, one end opening of the package 71 is connected to an end of an intermediate guide 82, and the tilting plate 78 and other parts are connected to each other. An empty jig 55 is placed on the side mounting guide 83, and the lower steel wire 59 of this jig 55 is inserted below the step 87 of the guide groove 86 as shown in FIG. By pushing up the gate body 61 of the jig 55 using the push-up pin 89, one end of the upper steel wire 60 is opened above the IC insertion opening 62 of the jig 55.

In this state, when the rotary actuator 79 is driven to tilt the tilting plate 78 to the opposite side as shown by the solid line in FIG.
The IC58 inside tries to slide downward under its own weight, but as shown in Fig. 16, the stopper pin 1
Since the lower end of the IC 58 protrudes into the guide concave portion 98, the IC 58 is once locked by the stopper pin 106. Therefore, when each stopper pin 106 is retreated from the guide groove 98 by pulling up the stopper actuating body 105 with the handle 111, the IC 58 slides downward passing between the stopper pin 106 and the guide groove 96. Then, as shown in FIG. 15, it is locked by a protruding gate pin 101. Here, the handle 11
When you release your hand from 1, the stopper pin 106 connects each IC.
The IC located in the middle of the row is connected to the spring 108,
110 to press against the guide protrusion 96 and hold it in a fixed position. Next, by pulling up the gate actuating body 100 with the handle 103, each gate pin 1
01 is retracted from the guide groove 98, a large number of ICs 58 between the stopper pin 106 and the gate pin 101 pass between the gate pin 101 and the guide protrusion 96, and are removed from the IC insertion opening 62 of the jig 55. The tool 55 is attached to the two lower steel wires 59 through the lower side of the gate body 61. At this time, the lower steel wire 5
9 is a mounting guide 8 as shown in FIG.
3, the lead frame 68 of the IC 58 slides on the step 87.

In this way, a large number of ICs 58 are connected to the lower steel wire 59.
When the jig 55 mounted above is lifted and removed from the mounting guide 83, the gate body 61 is pushed up by the push-up pin 89.
The upper steel wire 60 of each set is released and lowered.
Hold the upper part of both sides of the IC58 body, and
securely hold.

Next, the jig 55 loaded with the IC 58 in this manner is attached to the transport holder 29 in the soldering object receiving section 2 in FIG. 1 as shown in FIGS. 5 to 7. By this,
The IC 58 moves together with the transport holder 29 via the jig 55.

Then, as shown in FIG. 1, a water-soluble chlorine-based flux is applied to the lead frame 68 of the IC 58 in the fluxing unit 3, the excess flux is blown off with the air knife 4, and the lead frame 68 of the IC 58 is attached to the lead frame 68 in the preheating unit 5. 68 is heated, a solder film is applied to the lead frame 68 in the soldering unit 6, and hot water 24 or cooling 25 is applied from the upper shower 21 to the holder 29 and the jig 5 in the hot water cleaning unit 7 and the cold water cleaning units 8, 9, and 10.
At the same time, the jig 55 and the IC 58
The flux adhering to the holder 29, the jig 55, and the IC 58 is washed off, and the holder 29, the jig 55, and the IC are
Blow off the water droplets attached to the heating unit 1
4, the soldered material is dried by heat, and then cooled in the cooling fan unit 15.Finally, the jig 55 is removed from the holder 29 in the soldering object removal section 12 and taken out.

The jig 55 that accommodates the IC 58 with the solder film formed on the lead frame 68 in this way is
Installation guide 83 of soldering object transfer device 72
At the same time, a large number of empty packages 7 are positioned on the upper surface of the right side of the tilting plate 78 in FIG.
1 is fixed, and the tilting plate 78 is moved from the position shown by the solid line in FIG.
By rotating to the position indicated by the dotted chain line and pulling up the gate pin 101 and stopper pin 106, the IC 58 in the jig 55 can be easily returned to the empty package 71.

Note that an ultrasonic cleaning device may be incorporated in the hot water cleaning unit 7 and the cold water cleaning units 8, 9, and 10.

Effects of the Invention According to the present invention, since a hot water cleaning unit and a plurality of cold water cleaning units are sequentially arranged following the soldering unit, the objects to be soldered are first warmed by the hot water, so that a very small amount of soldering occurs. However, it expands and then contracts very slightly when cooled by cold water. Therefore, the water-soluble residual flux attached to the soldering object that changes in volume has a different rate of volume change due to temperature than the soldering object, so the swelling effect makes the water-soluble residual flux adhere to the soldering object. It peels off easily and can be effectively washed off with multiple cold water washing units. In other words, among the cold water cleaning units, the first cold water cleaning unit easily removes residual flux due to its relationship with hot water, and the second and subsequent cold water cleaning units
The flux can be effectively washed away. Further, since this cleaning unit is provided with an air bubbling water tank below the conveyor, residual flux can be effectively cleaned by causing the liquid rising with the bubbles, that is, the gas-liquid mixed phase upward flow, to collide with the soldering object. In particular, by applying irregular fine shock waves of hot and cold water to minute gaps such as those between IC lead frames, flux remaining in those minute gaps can be effectively washed away. Further, following this cleaning unit, a rotary air blow unit, a heating unit, and a cooling fan unit are sequentially provided, and since the rotary air blow unit blows air evenly onto the object to be cleaned while rotating, it is possible to Water droplets adhering to the object to be cleaned can be evenly removed by blowing them away evenly using the rotary air blow unit, and water, which is less volatile than solvents, can be pre-treated to dry the object in a short process. It can be applied equally to the entire object. Furthermore, the heating unit following this rotary air blow unit can dry the moisture in a short time, and the cooling fan unit can lower the temperature in a short time, making it possible to shorten the overall length of the conveyor. can.

[Brief explanation of drawings]

The figure relates to one embodiment of the present invention, and the first
The figure is a plan view of the automatic soldering device, and the second figure is the first
Figure 3 is a sectional view taken along the - line in Figure 1, Figure 4 is a sectional view taken along the - line in Figure 1, and Figure 5 is a sectional view taken along the - line in Figure 1.
The figures are a plan view of the transport holder and the jig, FIG. 6 is a partially cutaway front view thereof, FIG. 7 is a partially cutaway side view thereof, and FIG. 8 is an enlarged view of the main parts of FIG. Figure 9 is a perspective view showing how the IC is held by the jig;
The figure is a perspective view of the IC in the package cage, Figure 11 is a front view of the soldering object transfer device, Figure 12 is its top view, Figure 13 is its side view, and Figure 14 is its mounting guide. An enlarged sectional view, FIG. 15 is a sectional view of the gate portion of the intermediate guide, and FIG. 16 is a sectional view of the stopper portion of the intermediate guide. 1... Conveyor, 3... Fluxing unit, 5... Preheating unit, 6... Soldering unit, 7... Hot water cleaning unit, 8, 9, 10
...Cold water washing unit, 11...Drying means, 13
...Rotary air blow unit, 14...Heating unit, 15...Cooling fan unit, 20...
Air bubbling tank, 21...Shower, 68...
...IC lead frame as an object to be soldered.

Claims (1)

[Claims] 1 Along the conveyor that conveys the objects to be soldered, a fluxing unit, a preheating unit, a soldering unit are installed, and an air bubbling water tank is installed below the conveyor, and a shower is installed above the conveyor. An automatic soldering apparatus characterized in that a hot water cleaning unit and a plurality of cold water cleaning units are sequentially provided, and a drying means is formed by a rotary air blow unit, a heating unit, and a cooling fan unit.