JPH1093120A - Lead wire mounting apparatus - Google Patents

Abstract

PROBLEM TO BE SOLVED: To correct the positional deviations and straighten lead wires to be fed to electrodes. SOLUTION: The apparatus comprises a guide groove 20 for accurately guiding a lead wire 1 to an electrode and a press member 21 to press the wire 1 to the bottom 20a of the groove 20. When the wire 1 passes through the guide groove 20, it is regulated by the side wall of the groove 20 from lateral motions, to eliminate the positional deviation. The press member 21 presses the wire 1 to a bottom 20a of the groove so as to straighten in the thickness direction.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a lead wire attaching device for attaching a lead wire to an electrode of a substrate of a semiconductor device such as a solar cell.

[0002]

2. Description of the Related Art As shown in FIG. 10, a conventional lead wire mounting device for automatically connecting a lead wire to electrodes formed on the front and back surfaces of a solar cell substrate (hereinafter referred to as a cell) is shown in FIG. As a joining means for heating the tab 1a in order to connect the tab 1a to the cell 5 on the stage 4; A high-intensity lamp 6 is provided.
Here, the lead wire 1 cut into a predetermined length and temporarily placed on the electrode 7 is referred to as a tab 1a. In addition, the lead wire 1
Usually, a copper wire having a thickness of 150 μm is coated with solder, and the total thickness is about 200 μm. A supply means for supplying the lead wire 1 to the electrode 7 of the cell 5 is constituted by a roller or a chuck for transporting the reel 2, the tab cut portion 3 and the lead wire 1 from the reel 2 to the cell 5 on the stage 4. .

In this conventional apparatus, a cell 5 is placed on a stage 4.
Are supplied one after another, and the lead wire 1 is supplied from the reel 2 to the electrode 7 on the surface of the cell 5. And lead wire 1
Is set so as to be in contact with a predetermined position of the electrode 7, cut to a predetermined length by the tab cut section 3, and the tab 1 a is attached to the electrode 7.
Temporarily.

Then, the cell 5 on which the tab 1a is set is overlaid so that the electrode 7 on the back surface thereof is in contact with the tab 1a of the previous cell 5. By repeating this sequentially, the plurality of cells 5 are continuously connected via the tab 1a.

[0005] Then, the connected cells 5 are sequentially conveyed below the high-intensity lamp 6. When the cell 5 is transported under the high-intensity lamp 6, as shown in FIG. 11, the tab 1a has four pin-shaped pressing arms from above (hereinafter, referred to as holding pins).
Hold down with 8. The holding pin 8 is attached to a fixing tool 10 mounted on the stage 4 by a screw 9 with a fixing spring.
Fixed to

Then, the tab 1a is heated by the high-intensity lamp 6 while being held down by the holding pin 8 urged downward by the spring, and the solder of the tab 1a and the solder coated on the electrode 7 are reflowed. And the electrode 7 are joined. At this time, simultaneous wiring on the front and back surfaces is performed on the electrodes on the front and back surfaces of the cell 5. As a result, the plurality of cells 5 are sequentially connected to form a module.

[0007]

SUMMARY OF THE INVENTION Reel 2 of conventional device
Has a radius of about 20 cm and usually has four lead wires 1 in a row.
It is wound more than 00 laps. Lead 1 from this reel 2
Is supplied to the electrode 7 of the cell 5 due to burrs generated when the lead wire 1 is coated with solder, or the reel 1
The center position of the lead wire 1 is set to 0.6 to
A displacement of 0.8 mm results in a displacement of the electrode 7 from the center. Therefore, if a tab 1a having a width of 1 mm is set on the electrode 7 having a width of 1 mm, as shown in FIG. 12, when the contact surface (X portion) between the electrode 7 and the tab 1a is worst, 20% (0%) of the entire width is obtained. .2 mm), and the bonding strength between the electrode 7 and the tab 1a becomes insufficient if they are joined as they are. Therefore, in practice, the lead wire 1 having a width of about 2 mm is taken into consideration in consideration of the positional deviation between the tab 1a and the electrode 7.
Unavoidable, which hinders an improvement in the short-circuit current value and a reduction in the amount of material used.

Here, as an automatic lead wire attaching device,
"ADVANCED AUTOMATION TECH
NIQUES FOR INTERCONNECTIN
G THIN SILICON SOLAR CELL
S "(1st World Conference o
n Photovoltaic Energy Con
version, vol. 1, p. 828-831,1
994) has an image processing mechanism for eliminating the displacement of the tab 1a with respect to the electrode 7 of the cell 5. However, since this apparatus uses an image processing mechanism, the apparatus is very expensive.

Further, if there is a distortion in the thickness direction of the lead wire 1 caused during transportation or handling of the reel 2 for some reason, when the tab 1a is temporarily placed on the electrode 7, for example, as shown in FIG. The arm part projects upward. Therefore, in a later module manufacturing process,
The heating during laminating causes the EVA resin of the laminating material to swell, and the distorted portion of the tab 1a shifts in the outer peripheral direction of the module as shown in FIG. Also, the adhesive strength with the resin decreases, resulting in a defective product and a decrease in yield.

Since the tab 1a is usually coated with flux together with the solder, the contact portion between the pressing pin 8 and the tab 1a is formed when the solder of the tab 1a and the solder coated on the electrode 7 are reflowed. The deposition of the flux residue is repeated. Therefore, periodic cleaning of the holding pins 8 is indispensable, and it has been desired to reduce the number of the holding pins 8 in order to shorten maintenance time for removing, cleaning, and attaching the holding pins 8. However, the simple reduction of the number of the holding pins 8 is the same as that of the tab 1.
The contact point between a and the electrode 7 is reduced, and the high-speed heat treatment has a disadvantage that the adhesive strength of the entire cell 5 is insufficient and the yield is reduced.

SUMMARY OF THE INVENTION In view of the above, the present invention improves the yield by correcting a displacement and correcting a distortion when supplying a lead wire to an electrode, thereby improving the yield and further improving the maintainability. The purpose is to provide the device.

[0012]

SUMMARY OF THE INVENTION According to the present invention, there is provided a lead wire having supply means for supplying a lead wire to an electrode of a substrate and joining means for joining the lead wire to a predetermined position of the electrode. In the mounting device, a correction means for correcting distortion while correcting a displacement of the lead wire when supplying the lead wire to the electrode is provided. Therefore, the lead wire can be supplied to a predetermined position in a straight state without displacement of the lead with respect to the electrode. Therefore, it is not necessary to increase the width in consideration of the displacement of the lead wire, and a thin lead wire that is easily distorted can be used.

The correcting means comprises a guide groove for guiding the lead wire, and a pressing member for pressing the lead wire against the guide groove wall. The guide groove corrects the displacement and the pressing member corrects the distortion.

Further, a push arm for holding the lead wire at the time of joining the lead wire is provided, and the push arm is provided with a plurality of abutting portions at its tip for abutting on the lead wire. Therefore, the lead wire can be held in a wide range with one push arm, and the number of push arms can be reduced.

[0015]

DESCRIPTION OF THE PREFERRED EMBODIMENTS A lead wire attaching device (hereinafter, referred to as the present device) according to the present embodiment corrects a distortion while correcting a displacement of the lead wire 1 when supplying the lead wire 1 to the electrode 7 to a conventional device. Is provided. The same members as those of the conventional device are denoted by the same reference numerals.

As shown in FIGS. 1 and 2, the correcting means has a guide groove 20 for guiding the lead wire 1 and a pressing member 21 for pressing the lead wire 1 against a bottom surface 20a which is a guide groove wall.
The straightening is performed by passing the lead wire 1 through the guide groove 20. As shown in FIG. 3, a feed base 22 is provided between the reel 2 and the tab cut portion 3, and a guide groove 20 having a concave shape in the longitudinal direction is formed on an upper surface of the feed base 22. The feed base 22 and the cell 5 are positioned so that the center of the guide groove 20 and the center of the electrode 7 of the cell 5 are on the same straight line. The depth of the guide groove 20 is larger than the thickness of the lead wire 1, and the width is slightly larger than the width of the lead wire 1. For example, the width of the lead wire 1 is 1 mm
, The guide groove 20 has a width of 1.1 mm and a depth of 2.0 m.
m.

A guide groove 2 is provided on the upper portion of the feed base 22.
A cover 23 made of an acrylic resin is provided to cover the feed base 22 by two sets of mounting brackets 24. Note that the shape of the guide groove 20 need not be concave, but may be in accordance with the shape of the lead wire 1. For example, when the cross section of the lead wire 1 is round, FIG.
As shown in FIG.

The pressing member 21 is made of stainless steel and has the same structure as a ballpoint pen in which a ball 21b is fitted to the tip of a circular rod 21a having a diameter of 0.6 mm so that the ball 21b does not fall freely. And the pressing member 21 is a lid 23.
Is formed on the reel 2 side, and a hole is formed in the lid 23, and the cover 23 is fitted and fixed to the hole, or is bonded and fixed using an adhesive. Furthermore, it is inclined toward the moving direction of the lead wire 1 to prevent the lead wire 1 from being caught. The distance between the lowermost point of the pressing member 21 and the bottom surface 20a of the guide groove 20 is made smaller than the thickness of the lead wire 1. When the lead wire 1 passes through the gap, the pressing member 21
To a certain extent. The pressing member 21 only needs to press the lead wire 1 against the wall surface of the guide groove 20, and may be a rod-shaped member as shown in FIG. 5 which is bent in the moving direction of the lead wire 1.

Further, the amount of protrusion of the pressing member 21 from the lid 23 can be changed by changing the length of the rod 21a, changing the inclination, or the like, so that the lowermost point of the pressing member 21 and the bottom surface of the guide groove 20 are formed. If the distance from the lead wire 20a can be adjusted, it is possible to cope with various thicknesses of the lead wire 1, and the usability is improved. Further, the pressing member 21 may be configured not only to press the lead wire against the bottom surface but also to press the lead wire against the guide groove wall corresponding to the lid 23 which is the side surface or the upper surface of the guide groove 20.

In this apparatus, the holding pin 8 of the conventional apparatus is used.
Unlike this, as shown in FIG. 6, the holding pin 8 is formed in a Y-shape branched in two directions. That is, one pressing pin 8 has two contact portions 8a with the tab 1a. Thus, in order to obtain the same number of contact portions 8a as in the conventional device, only two pressing pins 8 are required. When the number of the contact portions 8a is four as shown in FIG. 7, only one pressing pin 8 is required. As shown in FIG. 8, the shape of the holding pin 8 may be a mountain shape (a), a wave shape (b), a ring shape (c), or a U-shape (d) in plan view.

In the above configuration, when the cell 5 is supplied to the stage 4 as in the conventional case, the lead wire 1 is supplied from the reel 2 to the electrode 7 of the cell 5. At this time, the lead wire 1 is passed through the guide groove 20 in advance, and is drawn out and supplied by a roller or a chuck. When the lead wire 1 passes through the guide groove 20, the left and right side walls of the guide groove 20 restrict the movement of the lead wire 1 in the left-right direction. That is, the lead wire 1 does not shift to the left and right, and if the center of the lead wire 1 is aligned with the center of the electrode 7 at a predetermined position, there is no shift between the centers.
Further, even if there is a distortion in the width direction of the lead wire 1, the distortion is corrected.

Further, when the lead wire 1 passes below the pressing member 21, the load is applied by the pressing member 21, and the lead wire 1 is sandwiched between the bottom surface 20a of the guide groove 20 and the ball 21b and pressed. That is, even if the lead wire 1 has a distortion in the thickness direction, the distortion is corrected. At this time, the ball 21b is rolling on the lead wire 1, the resistance to the advance of the lead wire 1 is small, and no disconnection or damage occurs.

As a result, the lead wire 1 supplied to the electrode 7 is set on the electrode 7 in a state where the distortion has been corrected without displacement. Thereafter, the lead wire 1 is cut at a predetermined length by the tab cut portion 3, and the tab 1 a is temporarily placed on the electrode 7 on the surface of the cell 5. Cell 5
Is transported on the stage 4 by a fixed distance by transporting by a conveyor or by a robot with the rear end of the tab 1a hanging.

Similarly, the tab 1a is set on the electrode 7 on the surface of the next cell 5. Then, transport the next cell 5,
The electrode 7 on the back surface of the next cell 5 is superimposed on the tab 1a of the previous cell 5. By repeating this, the tab 1a is set without displacement with respect to the electrode 7, and a plurality of cells 5 are continuously connected via the tab 1a.

When the connected cells 5 are conveyed under a high-intensity lamp 6 such as a halogen lamp or an infrared lamp, the tabs 1a temporarily placed on the electrodes 7 of the cells 5 are pressed from above by the pressing pins 8. As a result, the tab 1a and the electrode 7 come into close contact with each other. Then, while holding down the tab 1 with the holding pin 8
is heated by the high-intensity lamp 6 to reflow the solder of the tab 1a and the solder on the electrode 7 of the cell 5,
The tab 1a and the electrode 7 are joined. At this time, simultaneous wiring is performed for the electrodes 7 on the front and back surfaces of the cell 5. Thus,
A plurality of cells 5 are sequentially connected. It should be noted that the heat source is not limited to the lamp heater of the high-intensity lamp 6 but may be any heat source capable of melting the solder, and may be a sheathed heater or the like.

Here, the short-circuit current value is 3790 ± 10 mA
A comparison of the lead wire attachment results between the conventional apparatus and the present apparatus is performed for 100 normal 100 mm square silicon single crystal solar cells in the range of (1). However, the pressing member 21 was not attached, and the width of the lead wire 1 used in the conventional device was 2 mm,
The lead wire 1 in this device is 1 mm. The thickness of the lead wire 1 is a copper wire having a total thickness of 200 μm coated with a solder having a thickness of about 40 μm on one side, and is used by winding a length of about 200 m on a single-row reel 2 having a diameter of 20 cm.
The length of the guide groove 20 is 300 mm, and the width is 1.1 mm.
And

According to this, as shown in Table 1, the yield of the present device is 99.1%, whereas the yield of the conventional device is 99.0%, and the yield does not decrease. Therefore, in this device, the lead wire 1 can be thinned without lowering the yield, the occupation ratio of the tab 1a on the light receiving surface of the cell 5 can be reduced, the short-circuit current value can be improved, and the performance of the solar cell can be improved. Can be improved.

[0028]

[Table 1]

Next, using the present apparatus, a comparison is made between the above silicon single crystal solar cell and the presence or absence of the pressing member 21. However, the load on the lead wire 1 of the pressing member 21 is about 150 g. Further, in order to clarify the degree of reduction of the distortion of the lead wire 1 in the thickness direction, the lead wire 1 wound on the reel 2 is intentionally subjected to a distortion of about 1 mm in height in the thickness direction. The distortion is set to a total of 100 locations so as to be one location per cell.

According to this, the module yield when the pressing member 21 is attached is 99%, and the module yield when the pressing member 21 is not attached is 82%. Therefore, by attaching the pressing member 21, the yield is remarkably improved, and the production quality is improved. The module yield referred to here means that in the module process following the process of attaching the lead wire 1, the EVA resin swells due to heating during lamination, and the distorted portion of the tab 1a shifts in the outer peripheral direction of the module, and the base cell 5
Refers to the rate at which the surface is visible and does not become defective in appearance inspection.

Next, with respect to the above-mentioned silicon single crystal solar cell having the electrode 7 not coated with the solder, the holding pin 8 of the conventional device and (A)
A holding pin 8 having two contact portions 8a shown in FIG.
(B) The maintenance performance is compared with the holding pin 8 having the four contact portions 8a shown in FIG.

In this comparison, the tab 1a coated with the flux is used, and the heating time by the high-intensity lamp 6 is 4 seconds at a cell surface temperature of 250 ° C. or higher.
Then, in the maintenance of the holding pin 8 performed for every 800 sheets, the pin removal time and the pin mounting time after cleaning are actually measured, and the adhesive strength of the cell 5 and the average value of the fill factor (FF) are examined.

According to this, as shown in Table 2, the electrode 7
The total maintenance time required for attaching and detaching one presser pin 8 to one presser is 1
It has to be detached four times one by one, it takes 132 seconds,
In (A) of this device, only two times are required, and in 56 seconds, it is halved in comparison with the conventional device, and in (B) of this device, only one time is required.
It is about 20% in seconds compared to the conventional device. Therefore, the maintenance time is the shortest in (B) of the present apparatus. That is, as the number of contact portions 8a in one holding pin 8 increases, the maintenance time is reduced. Conversely, if it is too large, the load applied to one contact portion 8a is reduced and the pressing force is reduced.

[0034]

[Table 2]

Furthermore, their adhesive strength and FF show almost the same values, and the function of the pressing pin 8 of the present apparatus is the same as that of the conventional pressing pin 8.

As described above, when the guide groove 10 and the pressing member 11 are provided to correct the distortion while correcting the displacement of the lead wire 1 when supplying the lead wire 1 to the electrode 7, the structure becomes complicated. Instead, the lead wire 1 can be supplied to a predetermined position with a simple configuration without displacement of the lead wire 1 with respect to the electrode 7.
Therefore, it is not necessary to consider the displacement of the lead wire 1, and the lead wire 1 can be thinned without lowering the yield. As a result, the amount of material used can be reduced. Further, since the tab 1a is joined to a predetermined position of the electrode 7, the short-circuit current value can be improved. Therefore, the material cost can be halved with the improvement of the cell characteristics, and the production cost can be reduced.

Further, when the lead wire 1 is joined,
By using a plurality of contact portions 8a of the holding pins 8 for holding down, the number of the holding pins 8 can be reduced, and the maintenance time can be maintained without deteriorating the characteristics such as the adhesive strength between the lead wire 1 and the electrode 7. Time can be shortened, and maintainability can be improved. From the above, the cost can be significantly reduced in the manufacture of solar cells.

It should be noted that the present invention is not limited to the above-described embodiment, and it goes without saying that many modifications and changes can be made to the above-described embodiment within the scope of the present invention. For example, as shown in FIG. 9, when the correcting means is formed in the feed base 22 with a shape conforming to the shape of the lead wire 1, in this case, a hole 30 corresponding to the lead wire 1 having a circular cross section is formed, the lead wire 1 is guided and the distortion is caused. Can be corrected, and the need for the pressing member 21 is eliminated. In this case, if a taper is formed in the entrance 31 of the lead wire 1, the insertion of the lead wire 1 into this feed base becomes smooth. The hole 30 formed in the feed base 22 may have a triangular shape or a square shape according to the shape of the lead wire.

Further, the pressing member may be attached to the side wall or the bottom surface of the guide groove, and the lead wire may be pressed against the side or top lid. Further, a roller pressing member may be used instead of the rod-shaped pressing member. In the above embodiment, a single-row reel is used, but it goes without saying that the present invention can be applied to a multi-row reel.

[0040]

As is apparent from the above description, according to the present invention, when the lead wire is supplied to the electrode of the substrate, the electrode is provided with a correcting means for correcting the distortion while correcting the displacement of the lead wire. On the other hand, since the lead wire can be supplied to a predetermined position without displacement, it is not necessary to consider the displacement of the lead wire, and the lead wire can be thinned without lowering the yield. Therefore, the material used can be reduced, and the manufacturing cost can be reduced. Further, the occupancy of the tab on the light receiving surface of the cell can be reduced, the short-circuit current value can be improved, and the performance of the solar cell can be improved.

The straightening means comprises a guide groove for guiding the lead wire and a pressing member for pressing the lead wire against the guide groove wall, so that distortion in the vertical and horizontal directions can be corrected with a simple structure. Therefore, the quality is improved, the yield is improved, and the manufacturing cost can be reduced.

Further, if a push arm having a plurality of abutting portions that abut on the lead wire is provided at the end to hold the lead wire at the time of joining the lead wire, the bonding strength between the lead wire and the electrode is not reduced. In addition, the work required for attaching and detaching the push arm is reduced, so that the time required for maintenance can be shortened and the maintainability can be improved. Accordingly, work efficiency is improved, and manufacturing costs can be reduced.

[Brief description of the drawings]

1A and 1B show a straightening means of a lead wire attaching device according to an embodiment of the present invention, wherein FIG. 1A is a cross-sectional view, and FIG.

2 (a) is a plan view, FIG. 2 (b) is a side view, and FIG. 2 (c) is a front view.

FIGS. 3A and 3B show supply means, wherein FIG. 3A is a front view and FIG.

FIG. 4 is a view showing another guide groove.

FIG. 5 is a view showing another pressing member.

FIG. 6 is a perspective view of a push arm.

FIG. 7 is a perspective view of another push arm.

FIG. 8 is a plan view of another push arm.

9A and 9B show other correction means, in which FIG. 9A is a side view and FIG.
Is a vertical section

10A and 10B show a conventional lead wire mounting device, wherein FIG. 10A is a front view, and FIG.

FIG. 11 is a perspective view of a push arm.

FIG. 12 is a diagram showing a displacement of a lead wire with respect to an electrode.

FIG. 13 is a view showing distortion of a lead wire;

FIG. 14 is a diagram showing a displacement between a tab and an electrode.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Lead wire 1a Tab 2 Reel 3 Tab cut part 4 Stage 5 Cell 6 High intensity lamp 7 Electrode 8 Pressing pin 8a Contact part 20 Guide groove 20a Bottom surface 21 Pressing member

Claims (3)

[Claims] 1. A lead wire attaching device comprising: a supply means for supplying a lead wire to an electrode on a substrate; and a joining means for joining the lead wire to a predetermined position of the electrode. A straightening means for correcting a distortion while correcting a positional shift of the lead wire when supplying the lead wire to the lead wire. 2. The lead wire mounting device according to claim 1, wherein said straightening means comprises a guide groove for guiding said lead wire, and a pressing member for pressing said lead wire against a guide groove wall. 3. A push arm for holding said lead wire at the time of joining said lead wire, wherein said push arm is provided with a plurality of abutting portions at its tip for abutting on said lead wire. The lead wire mounting device according to claim 1 or 2, wherein