JP5498879B2 - Soldering apparatus and method - Google Patents

Description

  The present invention relates to a soldering apparatus and method for performing soldering on a linear part of a workpiece.

  Patent Document 1 discloses a soldering apparatus for soldering a lead wire to a solar cell. According to the soldering apparatus, a row of solder bumps is formed in advance at a constant pitch in the lead wire mounting region for a solar cell having lead wire mounting regions along the side portions on both sides of the solar cell. (Refer to FIG. 5 of Patent Document 1) The lead wire is pressed onto the row and the soldering iron is moved by one pitch of the solder bump to melt the solder bump so that the lead wire is attached to the solar cell lead wire. It is attached to the region (see paragraphs 0035 and 0036 of Patent Document 1).

  Patent Document 2 discloses a soldering apparatus that solders a ribbon wire to a metal back electrode layer laminated on a glass substrate in a solar cell (see FIG. 2 of Patent Document 2). According to the soldering apparatus, a row of preliminary solder is formed at a constant pitch on both sides of the metal back electrode layer, a ribbon wire is placed on the row, and the ultrasonic soldering iron is applied to the ribbon wire. While moving one pitch at a time, the ultrasonic soldering iron is applied to the upper surface side of the ribbon wire to melt the preliminary solder on the lower surface side, and the ribbon wire is fixed to the metal back electrode layer. (See, for example, FIG. 3 and paragraph 0020 of Patent Document 2).

  Patent Document 3 discloses a soldering apparatus that performs soldering on a linear part in a printed circuit board or the like (see, for example, 0001 in Patent Document 3). According to the soldering apparatus, the soldering amount per unit length in the linear portion is adjusted (see FIGS. 3 and 4 of Patent Document 3).

  In a soldering process in a solar cell, solder is linearly attached to a plurality of transparent electrodes arranged in a line and connected to each other. In the conventional soldering apparatus, the soldering iron is moved to the linear part by one movement of the soldering iron along the linear part, and the supply amount of the solder wire (thread solder) to the moving soldering iron is completed. Is not controlled according to the part on the linear part.

JP 2001-127322 A JP 2008-282919 A JP 11-138255 A

  The transparent electrode of the solar cell is made of, for example, ZnO (zinc oxide), and is not familiar with lead-free solder. Therefore, if the amount of solder supplied to the soldering iron is adjusted so that the soldering at the intermediate portion of the linear portion of the solar cell is appropriate, there is a problem that the soldering on the starting end side of the linear portion is likely to be faint. . In response to this, in the soldering on the start side of the linear part, if the supply amount of the solder wire to the soldering iron is increased, the solder in the range on the start end side becomes thicker than the allowable range, that is, solder damaging occurs. End up. It is very difficult to precisely adjust the amount of solder supplied to the soldering iron so as to avoid both blurring and soldering in the vicinity of the starting end of the linear part.

  The cited documents 1 and 2 do not mention soldering extending continuously in a linear shape. Although cited document 3 mentions the soldering extended linearly continuously, it does not explain how to deal with blurring or soldering in the vicinity of the starting end in that case.

  An object of the present invention is to provide a soldering apparatus and method for optimizing soldering that extends linearly while preventing blurring and soldering in the vicinity of the starting end of a linear part.

A first invention is a soldering apparatus for soldering a linear part of a workpiece that is not familiar with solder, a soldering iron, a moving device for moving the soldering iron relative to the workpiece, and the solder A solder supply device for supplying solder to the iron,
The control unit first positions the tip of the soldering iron at the beginning of the linear portion, which is the soldering start position of the workpiece, and approaches the workpiece closer to the workpiece so that the soldering tip can be soldered. The solder tip is moved to the position on the linear part while holding the approach position from the starting end while supplying solder to the solder iron from the solder supply device, and soldering is started. After the start of soldering, the solder tip stops at the first position where the tip moves on the linear portion by the first predetermined length from the starting end, while the tip is held at the approach position. The movement of the iron tip on the linear part is continued, and then the approach point is moved closer to the approaching point at a second position where the length from the starting end is longer than the first predetermined length on the linear part. From the position to the workpiece already It is located at a separation position separated from the workpiece so as to be separated from the attached solder, the tip is moved to the start end while maintaining the separation position, and the tip is moved closer to the workpiece from the separation position. The workpiece is brought into contact with the solder already attached to the starting end at the approach position, and the workpiece is moved again on the linear portion with the tip held at the approach position, and the workpiece is already moved along the linear portion. After the solder tip has passed through the first position, solder is supplied from the solder supply device to the solder iron at a third position moved by a third predetermined length from the starting end. The solder supply state of the solder supply device is controlled and the moving device is operated so as to resume and perform soldering after the third position .

According to the first invention, the soldering iron is moved twice from the beginning of the linear region towards the end, with respect to the solder deposited by transfer from the beginning of the first time to the first position, the second start end To the third position, the thickness of the solder is adjusted by dragging toward the end of the linear portion. Thereby, the thickness of the solder in the vicinity of the starting end of the linear portion is optimized, and it is possible to prevent the occurrence of fading and soldering dumming in the soldering near the starting end.

The second invention provides a soldering device of the first invention, the control unit, the amount of solder supplied is per unit length of the soldering iron of the solder supply apparatus, is better from the beginning to the first position Control is performed so as to be larger than the third and subsequent positions .

According to the second invention, with respect to the range from the starting end of the linear portion to the first position, the first solder deposited by moving the Handa trowel becomes thicker, the solder from the start of the solder is the second time the thicker The thickness is corrected by moving the iron. As a result, the thickness of the solder in the vicinity of the starting end of the linear portion can be optimized.

A third invention is a soldering method for performing soldering by moving a soldering iron to which solder is supplied to a linear part of a workpiece that is not familiar with soldering. First, the soldering is performed on the soldering iron. The soldering iron tip is positioned at the starting end of the linear portion, which is the soldering start position of the workpiece, and the soldering tip is positioned close to the workpiece so that the soldering can be performed. And starting soldering by supplying the solder iron to the soldering iron while moving the tip of the soldering iron from the starting end on the linear part while holding the approaching position, and after starting the soldering, the linear part The linear portion of the iron tip in a state where the supply of solder is stopped at the first position where the iron tip has moved a first predetermined length from the starting end while the iron tip is held at the approach position. Continue moving up, Thereafter, the solder tip is moved from the approach position to the solder that has already adhered to the workpiece at a second position where the length from the starting end is longer than the first predetermined length at a position on the linear portion. The tip is moved to the starting end while holding the separation position, and the tip is moved closer to the workpiece from the separation position to the approach position. The solder that has already adhered to the workpiece is brought into contact with the solder that has already adhered to the starting end, moved again on the linear part with the tip held in the approach position, and along the linear part. After the iron tip has passed through the first position, the supply of solder to the solder iron is resumed at a third position moved by a third predetermined length from the starting end, and the solder after the third position is resumed. It is carried out with And features.

According to a fourth invention, in the soldering method of the third invention, the amount of solder supplied to the soldering iron per unit length is larger from the starting end to the first position than from the third position onward. It is characterized by supplying as follows.

The main part block diagram of an automatic soldering apparatus. It is a figure which shows the location of the linear site | part where linear soldering is performed in a solar cell. It is explanatory drawing of the operation procedure of the ultrasonic soldering iron by a control part with respect to the soldering to the linear site | part of a solar cell. It is a figure which shows the state change of the solder in each progress time of operation of FIG.

  In FIG. 1, an automatic soldering apparatus 10 includes a three-dimensional movement apparatus 11 and a temperature control table 13 on which a solar cell 12 as a workpiece is placed on the upper surface. The temperature control table 13 is made of a hot plate, for example.

  The three-dimensional movement device 11 includes a horizontal bar 17 and a vertical bar 18. The horizontal bar 17 is supported by a column (not shown) supported by a base (not shown) so as to be movable in the Y-axis direction as the first horizontal direction so as to be movable in the Z-axis direction. The horizontal bar 17 also extends longer than the temperature adjustment table 13 in the X-axis direction as the second horizontal direction. The vertical bar 18 is supported by the horizontal bar 17 so as to be movable in the X-axis direction. The bracket 19 is fixed to the lower end portion of the vertical bar 18.

  The ultrasonic soldering iron 23 is attached to the bracket 19 so that the iron tip 24 is on the lower side and at an inclination angle of, for example, about 30 ° with respect to the horizontal direction. The solder wire feeder 27 is attached to the bracket 19, and the solder wire guide 28 has a proximal end portion fixed to the solder wire feeder 27 and a distal end portion reaching the vicinity of the tip 24. In the solder wire feeder 27, a coil of the solder wire 29 (FIG. 3) is set, and the solder wire 29 is drawn out from the coil and guided to the iron tip 24 through the solder wire guide 28.

  The ultrasonic soldering iron 23 corresponds to the soldering iron of the present invention. The soldering iron of the present invention is not limited to the ultrasonic soldering iron but may be a heater type soldering apparatus. The three-dimensional moving device 11 corresponds to the moving device of the present invention. The moving device of the present invention is not limited to a three-dimensional moving device, and may be a device that moves the soldering iron only in the X-axis and Y-axis directions.

  The control unit 31 includes a memory for storing data and a program, and a CPU for executing the program. The control unit 31 sends a control signal to the Z-axis servo 32 and the X-axis servo 33, via the Z-axis servo 32 and the X-axis servo 33. The position of the horizontal bar 17 in the Z-axis direction and the position of the vertical bar 18 in the X-axis direction are controlled. The X coordinate and Z coordinate of the tip 24 of the ultrasonic soldering iron 23 are uniquely determined by the position of the vertical bar 18 in the X-axis direction and the position of the horizontal bar 17 in the Z-axis direction.

  FIG. 2 shows a straight portion 36 in the solar cell 12. The solar cell 12 has a rectangular plate shape and is obtained by laminating a back electrode tank, a light absorption layer, and a transparent electrode layer on a glass substrate. The straight portion 36 extends over the entire length of the solar cell 12 in the X-axis direction along the left and right side portions of the transparent electrode layer, that is, the side portions on both sides in the Y-axis direction of the solar cell 12. The ultrasonic soldering iron 23 attaches solder to the left and right linear portions 36 over its entire length. The linear soldering to the straight portion 36 has an effect of reducing the electrode resistance when a lead wire or the like is connected later to the soldering.

  The work of the present invention is not limited to the solar cell 12. Any work having a linear soldering part such as the straight part 36 may be used. The linear site | part of this invention is not limited to linear form. What is necessary is just to extend in the continuous line shape of the predetermined length which has a start end and a termination | terminus, such as a curve and a bending line.

  FIG. 3 is an explanatory diagram of an operation procedure of the ultrasonic soldering iron 23 by the control unit 31 for soldering the solar cell 12 to the linear portion 36. The change in the state of the solder film formed on the straight portion 36 by the execution of the operation procedure will be described later with reference to FIG. In this solar cell 12, the total length of the linear portion 36, that is, the length of the solar cell 12, is assumed to be 720 mm. Further, it is assumed that the thickness of the solder film formed on the straight portion 36 is 0.1 mm or less. The solder material is a lead-free material.

  In FIG. 3, the horizontal direction coincides with the X-axis direction in the automatic soldering apparatus 10. Ps and Pe are defined as the start end and the end of the straight line portion 36, respectively. The coordinate unit is mm, and the origin is set to Ps. The X coordinate of Ps = 0 and the X coordinate of Pe = 720. In FIG. 3, P1 to P5 are defined in addition to Ps and Pe. Regarding the X coordinates of P1 to P5, Ps <P1 <P2 <P3 <P4 <Pe <P5. Length between Ps and P1: The length between P1 and Pe is, for example, 1: 9.

  In FIG. 3, “supply pull” means moving the tip 24 in the positive direction of the X axis while supplying the solder wire 29 to the tip 24. “Empty pulling” means that the supply of the solder wire 29 to the tip 24 is stopped and the tip 24 is moved in the positive direction of the X axis. “Escape cut” means that the ultrasonic soldering iron 23 continues to move in the positive direction of the X axis even after the tip 24 reaches Pe. The inside is decelerated and stops at the end point P5 of the “escape”. The solder wire 29 is not supplied to the tip 24 while the tip 24 is “run away”. “Return” means that the tip 24 is moved in the negative direction of the X axis. During the “returning”, the supply of the solder wire 29 to the iron tip 24 is naturally stopped.

  Furthermore, an “approaching position” and a “separation position” are defined for the ultrasonic soldering iron 23 (tip 24). The “approaching position” is defined as a position in the Z-axis direction where the ultrasonic soldering iron 23 attaches solder to the linear portion 36 while moving in the positive direction of the X-axis. Further, the side where the iron tip 24 is separated from the solar cell 12 in the Z-axis direction is the positive side, and the “separation position” is the Z-axis direction separated from the solder already attached to the linear portion 36 toward the Z-axis direction positive side. Define as position. Therefore, as long as the ultrasonic soldering iron 23 is held at the “separation position”, the tip 24 contacts the solder dama on the straight portion 36 regardless of the X coordinate and Y coordinate of the ultrasonic soldering iron 23. There is no.

  Specifically, the “approach position” is a position of the solid iron tip 24 in FIGS. 4A, 4B, 4D, and 4E described later, and the “separation position” is a diagram described later. This is the position of the solid iron tip 24 in 4 (c). In the above-described “escape”, the ultrasonic soldering iron 23 may be moved in the X-axis direction while holding the Z coordinate in the approach position, or may be moved in the X-axis direction while increasing the Z coordinate. May be.

  The control unit 31 performs soldering on the straight part 36 in the order of operations 1, 2, and 3. In this example, the temperature of the iron tip 24 is not particularly controlled from the start of the operation 1 to the end of the operation 3, and is maintained at a temperature equal to or higher than the melting temperature of the solder wire 29. In addition, when the linear portion 36 to be soldered is changed to another one after the operation 3 is finished, the ultrasonic operation of the ultrasonic soldering iron 23 is usually stopped.

  For the programming of the position control of the ultrasonic soldering iron 23 by the control unit 31 via the three-dimensional moving device 11, teaching is appropriately used for a plurality of specific positions of the ultrasonic soldering iron 23.

  In operation 1, the tip 24 is moved from Ps to P3 in the X-axis direction while being held at the approach position. In operation 1, in the movement range from Ps to P1, the tip 24 is supplied, and in the movement range from P1 to P3, the tip 24 is empty. The X coordinate of the tip 24 that is moving in the X-axis direction may be detected from a feedback signal from the X-axis servo 33, or the elapsed time from the start of movement in the X-axis direction from Ps is measured, and P1 , P3 may be determined as the arrival time of P1 and P3. The same applies to the case where the arrival of the tip 24 to P2, P4, Pe, and P5 described later is detected.

In operation 2, the tip 24 is returned from P3 to Ps in the X-axis direction while holding the tip 24 at the separation position.

In operation 3, the tip 24 is moved from Ps to P5 in the X-axis direction while being held at the approach position again. In operation 3, in the movement range from Ps to P2, the iron tip 24 is empty, in the movement range from P2 to P4, the iron tip 24 is supplied, and in the movement range from P4 to Pe, The tip 24 is emptied, and in the movement range from Pe to P5, the tip 24 is completely escaped.

  FIG. 4 shows a change in the state of the solder 40 at each progress point of the operation of FIG. Time elapses in the order of FIGS. FIG. 4A shows a state at the start of supply pulling in operation 1. FIG. 4B shows a state at the end of emptying in operation 1. FIG. 4C shows a state at the end of the operation 2. FIG. 4D shows a state at the start of the first emptying in the operation 3. FIG. 4E shows a state after the start of supply pulling in operation 3.

  With reference to FIG.3 and FIG.4, the state change of the solder 40 in the linear part 36 accompanying each operation is demonstrated. In FIG. 4, D1 and D5 indicate the movement of the tip 24 toward the positive side in the X-axis direction, and D3 indicates the movement of the tip 24 toward the negative side in the X-axis direction. D2 indicates the movement of the tip 24 toward the positive side in the Z-axis direction, and D4 indicates the movement of the tip 24 toward the negative side in the Z-axis direction. Further, the tip 24 is switched between the approach position and the separation position in the Z-axis direction, and the tip 24 in FIGS. 4A, 4B, 4D, and 4E is in the “approach position”. In 4 (c), the upper two iron tips 24 are in the “separation position”, and the lower iron tip 24 is in the “approach position”.

  The supply amount of the solder wire 29 to the soldering tip 24 is such that the soldering amount per unit length of the straight portion 36 in the operation 1 supply pull is the soldering amount per unit length of the straight portion 36 in the operation 3 supply pull. It is controlled to be larger. For example, the thickness of the solder 40 by soldering to the straight portion 36 in the supply pull of operation 1, that is, the thickness of the solder 40 in FIGS. 4A to 4C is slightly larger than the upper limit of the allowable range. And solder. On the other hand, the thickness of the solder 40 by soldering to the straight portion 36 in the supply pull of operation 3, that is, the thickness of the solder 40 in FIG. .

  Note that the solder 40 attached to the vicinity of Ps of the straight portion 36 in the operation 1 is not limited to the solder supplied from the solder wire feeder 27 to the soldering tip 24 during the supply pulling period of the operation 1 for the straight portion 36 this time. The solder remaining on the iron tip 24 from the end of the previous operation 3 to the start of the current operation 1 may also be included. In this case, the adhesion amount of the solder 40 near Ps by the operation 1 is larger than the current supply amount of the solder wire 29 to the tip 24.

  As a result of the large amount of soldering to the linear part 36 in the supply pull of operation 1, the solder fading is prevented in the vicinity of Ps of the linear part 36. However, on the other hand, the amount of adhesion becomes an over-atmosphere, and as shown in FIG. 4 (b), the solder dam 41 is likely to occur in the vicinity of Ps. The thickness of the solder 40 in the solder dama 41 exceeds the upper limit of the allowable range for the thickness of the solder 40.

  After the end of the operation 1, the operation 2 is performed. As a result, the tip 24 is switched from the approach position to the separation position as shown in FIG. 4C, and returned to Ps while being held at the separation position.

  As the operation 3 starts, the tip 24 is applied to the solder dama 41. With the contact of the tip 24 to the solder dama 41 in operation 3, the solder dama 41 is remelted. As shown in FIG. 4D, the solder blank 41 is brought into contact with the iron tip 24 on the negative surface in the X-axis direction as shown in FIG. Extruded to the positive side in the axial direction. Thereby, as shown in FIG. 4E, the thickness of the solder 40 is adjusted within the distance between the straight portion 36 and the tip 24, that is, the allowable thickness range, and the solder dama 41 is removed. . Further, the excess solder of the solder dama 41 is used for soldering between P1 and P2 (FIG. 3) in the straight portion 36.

  Before the extension of the solder 40 by the excess solder of the solder dama 41 is finished, the supply of the solder wire 29 to the tip 24 is resumed, and the solder 40 to the straight portion 36 is continuously formed up to Pe without interruption. Is done.

  With respect to the moving speed of the ultrasonic soldering iron 23 in the X-axis direction, both operations 1 and 3 are increased from the speed 0 at the start and decelerated to 0 at the end. In the middle, it is maintained at a constant speed. However, in the supply pull of operation 3, the speed is increased at the start accompanying the switching from the idle pulling, and then becomes a constant speed. In order to ensure the correction of the solder dama 41 in the first emptying in the operation 3, the moving speed of the emptying in the operation 3 is set low. In operation 3, the maximum movement speed in the X-axis direction between Ps and P2 is set to 1/30 to 1/2 of the maximum movement speed in the X-axis direction between P2 and Pe.

  Typically, the maximum movement speed in the X-axis direction between Ps and P2 in operation 3 is maintained as soon as the initial speed increase is completed, and then maintained until the ultrasonic soldering iron 23 (iron tip 24) reaches P2. Is done. Typically, the maximum moving speed in the X-axis direction between P2 and Pe in the operation 3 is generated as soon as the speed increase from P2 is completed, and then maintained until the ultrasonic soldering iron 23 reaches Pe.

  The present invention is not limited to the above-described embodiments, and various modifications (including addition and deletion) are possible without departing from the spirit of the present invention.

10: automatic soldering device (soldering device), 11: three-dimensional moving device (moving device), 12: solar cell (work), 23: ultrasonic soldering iron (soldering iron), 29: solder wire, 31: control Part, 36: linear part, 40: solder, 41: solder dama.

Claims (4)

A soldering device that performs soldering on a linear part of a workpiece that is not familiar with solder,
With soldering iron,
A moving device for moving the soldering iron relative to the workpiece;
A solder supply device for supplying solder to the solder iron;
A controller for controlling the movement of the solder iron by controlling the moving device and controlling the solder supply state to the solder iron by controlling the solder supply device ;
The controller is
First, the tip of the soldering iron is positioned at the starting end of the linear part that is the soldering start position of the workpiece, and the tip of the soldering iron is positioned at an approaching position close to the workpiece so that soldering can be performed,
While supplying the solder from the solder supply device to the solder iron, the soldering tip is moved from the starting end on the linear portion while holding the approach position to start soldering,
After the soldering is started, the solder tip is stopped at the first position where the tip moves on the linear portion by a first predetermined length from the start end, while the tip is held at the approach position. Continue the movement of the tip of the iron tip on the linear part,
Thereafter, at the second position where the length from the starting end is longer than the first predetermined length on the linear portion, the tip of the iron is separated from the approach position with respect to the solder already attached to the workpiece. Is moved to a separation position separated from the workpiece, and the tip is moved to the starting end while maintaining the separation position,
The soldering tip is brought close to the workpiece from the separation position and positioned at the approach position to contact the solder already attached to the starting end,
With the tip held in the approach position and moving again on the linear part, extending the solder already attached to the workpiece along the linear part,
After the iron tip passes through the first position, the supply of solder from the solder supply device to the solder iron is resumed at a third position moved by a third predetermined length from the starting end, and after the third position. A soldering apparatus that controls a solder supply state of the solder supply apparatus and operates the moving device so as to perform soldering. The soldering apparatus according to claim 1,
The control unit controls the supply amount of the solder to the solder iron of the solder supply device per unit length so that the distance from the start end to the first position is larger than that after the third position. A soldering apparatus characterized by that. A soldering method for performing soldering by moving a soldering iron to which solder is supplied to a linear part of a workpiece that is not familiar with solder,
First, in a state where no solder is supplied to the soldering iron, the soldering iron tip is positioned at the starting end of the linear portion, which is the soldering starting position of the workpiece, and the soldering tip can be soldered. Positioned at an approach position close to the workpiece,
While supplying the solder to the soldering iron, the soldering tip is moved on the linear part while holding the approach position from the starting end, and soldering is started.
After the soldering is started, the solder tip is stopped at the first position where the tip moves on the linear portion by a first predetermined length from the start end, while the tip is held at the approach position. Continue the movement of the tip of the iron tip on the linear part,
Thereafter, at the second position where the length from the starting end is longer than the first predetermined length on the linear portion, the tip of the iron is separated from the approach position with respect to the solder already attached to the workpiece. Is moved to a separation position separated from the workpiece, and the tip is moved to the starting end while maintaining the separation position,
The soldering tip is brought close to the workpiece from the separation position and positioned at the approach position to contact the solder already attached to the starting end,
With the tip held in the approach position, moving the linear part again and extending the solder already attached to the workpiece along the linear part,
After the soldering tip passes through the first position, the supply of solder to the soldering iron is resumed at a third position moved by a third predetermined length from the starting end, and soldering after the third position is performed. A soldering method characterized by the above. The soldering method according to claim 3,
A soldering method, wherein the amount of solder supplied to the soldering iron is supplied so that the distance from the start end to the first position per unit length is larger than that after the third position .

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