JPH08276266A - Soldering method and its equipment - Google Patents

Abstract

PURPOSE: To realize the soldering of excellent productivity in a short time by detaching a heating member from a heat transfer member pressed against the part to be soldered, abutting a cooling member thereon to cool the heat transfer member to promote the solidification of the solder. CONSTITUTION: The paste 6 is applied to a foot land 7 of a printed circuit board 5, and a lead part 4 of an electronic parts is laminated thereon. A heater 19 is energized by a temperature adjuster 26 to heat a heating member 20 up to a prescribed temperature together with a heat transfer member 21, a motor 16 for elevation/lowering is driven by the command from a controller 29, an elevating/lowering head 14 is lowered to press the heat transfer member 21 against the lead part 4, and the paste 6 is melted by the heat of the heat transfer member. Compressed air is fed to an air cylinder 22, and the heating member 20 is detached upward from the heat transfer member 21 to stop the heating, and a cooling member 23 is moved and pressed against the heat transfer member 21, which is cooled with the refrigerant. The soldering excellent in the productivity can be achieved making use of the heat transfer.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a soldering method and an apparatus for soldering electronic parts to a printed wiring board.

[0002]

2. Description of the Related Art Electronic components mounted on a printed wiring board are usually attached to a tape-shaped insulating film at regular intervals, and as shown in FIG.
The lead portion 4 of the electronic component 3 together with the support ring 2 formed of the insulating film 1 is cut from the tape-shaped insulating film 1 if necessary, and the lead portion 4 is bent into a predetermined shape. When the electronic component 3 is soldered to a printed wiring board, the solder paste 6 is applied to the foot lands of the wiring pattern formed on the printed wiring board 5, as shown in FIG. 10 showing the appearance of the printed wiring board.
Is applied by a screen printing method or the like, the lead portion 4 of the electronic component 3 is superposed on the foot land through the solder paste 6, and the solder paste 6 is melted by heating them to form the printed wiring board 5. The electronic component 3 is soldered.

FIG. 11 shows an example of a conventional soldering apparatus used for such soldering. That is, the elevating head 104 is rotated through the pair of upper and lower pins 105 to the other end of the swing lever 103 whose one end is pivotally attached to the frame 101 through the pair of upper and lower pins 102, respectively. These pins 102, 10 are rotatably pivotally attached.
5 and the rocking lever 103 form a parallelogram link mechanism. A ball nut (not shown) that is screwed into a ball screw shaft 107 that can be rotated in the forward and reverse directions by a lifting drive motor 106 attached to the frame 101 is incorporated in the lifting head 104. By operating and rotating the ball screw shaft 107, the lifting head 10 is moved with respect to the frame 101.
4 can be raised and lowered.

It should be noted that the pin 10 is provided so that the elevating head 104 can smoothly ascend and descend with the rotation of the ball screw shaft 107.
5, the fitting hole 108 formed at the other end of the swing lever 103 is an elongated hole extending along the longitudinal direction of the swing lever 103.

At the lower end of the elevating head 104, a heating member 110 incorporating a heater 109, an air cylinder 112 having a heat transfer member 111 fixed to the tip of a piston rod (not shown), and a compressed air supply source (not shown). A cooling nozzle 113 for blowing cooling air onto the heat transfer member 111 to solidify the solder in a molten state is fixed. The temperature of the heating member 110 is controlled to a predetermined temperature by a temperature adjuster 115 that controls energization of the heater 109 via a thermocouple thermometer 114. Further, the heat transfer member 111 is pressed against the lead portion 4 of an electronic component (not shown) which is superposed on the foot land 7 of the printed wiring board 5 via the solder paste 6, and transfers the heat energy generated by the heating member 110. A thermocouple thermometer 11 for melting the solder paste 6.
The temperature is discriminated by the discriminator 117 via the controller 6, and the controller 11 is determined based on the information from the discriminator 117.
8 is a lifting drive motor 106 and an air cylinder 112.
Air is supplied to and discharged from.

Therefore, the elevating drive motor 106 is operated based on a command from the controller 118, and the elevating head 104 is lowered together with the heating member 110 and the heat transfer member 111, so that the heat transfer member 111 is a lead portion of an electronic component. The heating member 11 is pressed against the solder paste 6 through the heat transfer member 111 that is pressed against the heating member 110 and contacts the heating member 110.
The heat energy generated at 0 is transmitted, and the solder paste 6 is melted. Then, after a predetermined time, based on a command from the controller 118, the lifting drive motor 106
However, since the pressurized air is supplied to the air cylinder 112, the heat transfer member 111 is still pressed against the lead portion 4 of the electronic component even when the elevating head 104 is raised. At, the cooling air is blown from the cooling nozzle 113 onto the heat transfer member 111.

Thus, the heating member 110 is separated from the heat transfer member 111 to stop the supply of heat energy to the heat transfer member 111, and the heat transfer member 1 is connected to the lead portion 4 of the electronic component.
11 is kept pressed, the molten solder is solidified by the cooling air from the cooling nozzle 113, and the foot land 7 of the printed wiring board 5 and the lead portion 4 of the electronic component are soldered. Then, it is determined by the thermocouple thermometer 116 that the heat transfer member 111 has reached a predetermined temperature by a determination unit 117.
In accordance with the command from the controller 118, the supply of the pressurized air to the air cylinder 112 is stopped, and the heat transfer member 111 is pulled up from the lead portion 4,
Further, the blowing of the cooling air from the cooling nozzle 113 to the heat transfer member 111 is stopped.

[0008]

In the conventional soldering apparatus shown in FIG. 11, cooling air is blown in order to solidify the solder in a molten state. Therefore, there is a problem that the cooling efficiency is not so good.

The lead portion 4 has a high temperature heat transfer member 111.
Since the heat transfer members 111 are in contact with each other, it is necessary to cool the heat transfer member 111 at the same time, and the time required for this cooling increases, and the time for soldering becomes long in combination with the poor cooling efficiency. . As a result, the productivity is low and the cost is increased.

[0010]

SUMMARY OF THE INVENTION It is an object of the present invention to provide a soldering method and an apparatus therefor capable of shortening the time required for soldering by efficiently cooling a heat transfer member.

[0011]

According to a first aspect of the present invention, a step of bringing a heat transfer member into contact with a heating member incorporating a heater to raise the temperature of the heat transfer member, and receiving heat from the heating member. And pressing the heat transfer member to the soldering target portion, melting the solder interposed in the soldering target portion, and releasing the heating member from the heat transfer member pressed to the soldering target portion, , A step of cooling the soldering target portion by bringing a cooling member into contact with the heat transfer member pressed against the soldering target portion and absorbing heat from the heat transfer member. It is in the soldering method.

According to a second aspect of the present invention, a heater is incorporated and is supported by a main body frame so as to be reciprocally movable in the first direction, and the heating member is driven in the first direction. Heating member driving means, a heat transfer member that can be brought into contact with the heating member and is pressed against the soldering target portion, and that can reciprocate in the first direction with respect to the heating member, and the heat transfer member. A heat transfer member driving means that drives in a first direction, and a reciprocating member that can contact the heat transfer member to cool the heat transfer member and that can reciprocate in a second direction that intersects the first direction. And a cooling member driving means for driving the cooling member in the second direction.

Here, the cooling member includes a casing,
There may be a refrigerant passage formed in the casing, and a refrigerant may be supplied to the refrigerant passage, and a portion of the cooling member that abuts the heat transfer member is a rubber-like elastic body. Are preferably formed.

[0014]

According to the present invention, the heating member incorporating the heater is moved together with the heat transfer member in the first direction by the heating member driving means, and the heat transfer member is pressed against the soldering target portion. The heating member raises the temperature of the heat transfer member, thereby melting the solder interposed in the soldering target portion. Next, while keeping the heat transfer member pressed against the soldering target portion by the heat transfer member driving means, the heating member is separated from the heat transfer member by the heating member driving means,
The heating of the heat transfer member is stopped, the cooling member is moved in the second direction by the cooling member driving means, and the cooling member is brought into contact with the heat transfer member to absorb the heat of the heat transfer member by heat conduction. The part to be attached is cooled to solidify the molten solder. Then, the heat transfer member driving means separates the heat transfer member from the soldering target portion.

When the cooling member has the casing and the refrigerant passage formed in the casing to supply the refrigerant, the cooling of the cooling member itself after absorbing the heat of the heat transfer member is accelerated, and the heat transfer member absorbs heat. It is done efficiently. Further, when the portion of the cooling member that contacts the heat transfer member is formed of a rubber-like elastic body, the rubber-like elastic body elastically deforms in accordance with the pressing operation of the cooling member against the heat transfer member, and the heat transfer member and the cooling member. The contact state with is improved, the contact area is expanded, and the heat transfer member absorbs heat efficiently.

[0016]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment in which the present invention is applied to soldering an electronic component and a printed wiring board shown in FIGS. 9 and 10 will be described in detail with reference to FIGS.

As shown in FIG. 1, which shows the schematic structure of the present embodiment, one end of each is pivotally attached to a frame 11 via a pair of upper and lower pins 12, and the other end of a swing lever 13 is rotatably attached. The lifting head 14 is rotatably pivoted via a pair of upper and lower pins 15, and the pins 12, 15 and the swing lever 13 form a parallelogram link mechanism. Further, a ball nut (not shown) that is screwed with a ball screw shaft 17 that can be rotated in the forward and reverse directions by a lifting drive motor 16 attached to the frame 11 is incorporated in the lifting head 14. By operating to rotate the ball screw shaft 17, the elevating head 14 can be moved up and down with respect to the frame 11.

A fitting hole 18 formed at the other end of the rocking lever 13 with respect to the pin 15 is provided so that the elevating head 14 can be smoothly moved up and down as the ball screw shaft 17 rotates.
Is an elongated hole extending along the longitudinal direction of the swing lever 13. In this embodiment, the pins 12, 15 and the rocking lever 13, the raising / lowering drive motor 16, the ball screw shaft 17 and the like constitute the heating member drive means of the present invention.

At the lower end of the elevating head 14, a heating member 20 having a heater 19 incorporated therein and a heat transfer member 21 fixed to the tip of a piston rod (not shown) are used as the heat transfer member driving means of the present invention. Drive air cylinder 22
And a pair of left and right female screw pins 24 for mounting a cooling member 23 described later are fixed.

The heating member 20 includes the heating member 20.
A thermocouple thermometer 25 for detecting the temperature is attached, and the detection signal of the thermocouple thermometer 25, that is, the temperature information of the heating member 20 is output to the temperature controller 26.
The temperature adjuster 26 controls energization of the heater 19 based on the output of the thermocouple thermometer 25 so that the heating member 20 reaches a predetermined temperature, for example, 300 ° C.

Further, the heat transfer member 21 is pressed against the lead portion 4 of an electronic component (not shown) which is superposed on the foot land 7 of the printed wiring board 5 via the solder paste 6.
This is for transmitting the heat energy generated in the heating member 20 to melt the solder paste 6, and the heat transfer member 21 is provided with a thermocouple thermometer 27 for detecting the temperature of the heat transfer member 21. The detection signal of this thermocouple thermometer 27,
That is, the temperature information of the heat transfer member 21 is output to the determination unit 28. The determination unit 28 determines whether or not the temperature of the heat transfer member 21 is equal to or lower than a predetermined temperature based on the output of the thermocouple thermometer 27, and when it is determined that the temperature is equal to or lower than the predetermined temperature, A signal to that effect is output to the controller 29. Then, the controller 29, based on the information from the determination unit 28, the lifting drive motor 16 and the heat transfer member drive air cylinder 22,
In addition, the operation of a slider driving air cylinder 36, which will be described later, is controlled.

FIG. 1 and FIG. 2 in which a portion of the cooling member 23 is extracted and enlarged, and FIG. 3 showing a sectional structure taken along the line III-III thereof.
As shown in FIG. 4 showing the IV-IV arrow cross-sectional structure, the guide pins 30 are respectively provided on the pair of left and right female screw pins 24 screwed to the lower end of the elevating head 14.
Are coaxially screwed, and sliders 31 are attached to the guide pins 30 so as to be slidably engaged with the guide pins 30 in the left-right direction in FIG. The cooling member 23 located on the side of the heat transfer member 21 is integrally connected to the slider 31 via an arm portion 32. Therefore, the slider 31 can be slid with respect to the guide pin 30. As a result, the cooling member 23 reciprocates in the direction opposite to the heat transfer member 21 (left and right direction in FIG. 1), and comes into contact with the heat transfer member 21 at the forward end side thereof.

A compression coil spring 33 for urging the slider 31 against the guide pin 30 in a direction in which the cooling member 23 separates from the heat transfer member 21 is incorporated in the slider 31, and the compression coil spring 33 is pulled out from the slider 31. The lid plate 34 is attached to the slider 31 so as not to come off. A wedge block 35, which is tapered toward the lower side, is in contact with the end of the slider 31 on which the compression coil spring 33 is incorporated. The wedge block 35 is attached to the upper end of the frame 11 for driving the slider. It is integrally fixed to the lower end of the piston rod 37 of the air cylinder 36. That is, when the piston rod 37 of the slider driving air cylinder 36 is extended downward together with the wedge block 35, the slider 31 is moved against the spring force of the compression coil spring 33.
The inside of the cooling member 23 is moved to the left side, and the cooling member 23 is pressed against the heat transfer member 21.

In this embodiment, in order to suppress the deflection of the long piston rod 37, the piston rod 3
A guide member 38 slidably engaged in the middle of 7 is fixed to the frame 11. Further, the cooling member driving means of the present invention is constituted by the guide pin 30, the slider 31, the compression coil spring 33, the wedge block 35, the slider driving air cylinder 36, etc. described above.

A cooling medium passage (not shown) is formed in the cooling member 23, and a cooling medium introducing pipe 39 for supplying a cooling medium (not shown) such as water to the cooling medium passage is provided at both ends of the cooling medium passage.
Refrigerant discharge pipe 4 for guiding the refrigerant flowing in the refrigerant passage to the outside
0 is connected to the heat transfer member 2 efficiently.
The heat absorption of 1 can be performed. In addition, a rubber-like elastic body 41 is attached to the cooling member 23 on the side facing the heat transfer member 21 in order to enhance the adhesion between the heat transfer member 21 and the cooling member 23 and enhance the thermal conductivity. In the rubber-like elastic body 41 in the present embodiment, metal powder for enhancing the thermal conductivity is kneaded in a dispersed state.

The operation procedure using the above-mentioned soldering device will be described with reference to FIGS. 5 to 8. The solder paste 6 is applied on the foot land 7 formed on the printed wiring board 5 in advance, and the solder paste 6 is applied on the foot land 7. The lead parts 4 of the electronic parts (not shown) are superposed on each other. On the other hand, the temperature controller 26
Thus, the heater 19 is energized to heat the heating member 20 to a predetermined temperature together with the heat transfer member 21 which is in contact with the heating member 20 (see FIG. 5).

In this state, the elevating drive motor 16 is operated based on a command from the controller 29 to rotate the ball screw shaft 17 in the normal direction, and the elevating head 14 is lowered to push the heat transfer member 21 to the lead portion 4. Hit As a result, the heat of the heat transfer member 21 is transferred from the lead portion 4 to the solder paste 6, and the solder paste 6 is melted. The time required for this is stored in the controller 29 in advance and is set to 2 to 3 seconds in the present embodiment (see FIG. 6).

Next, the elevating drive motor 16 operates to reverse the ball screw shaft 17 to raise the elevating head 14 while supplying compressed air to the heat transfer member drive air cylinder 22 to supply the heat transfer member 21. Is continuously pressed against the lead portion 4, the heating member 20 is separated from the heat transfer member 21 upward, and heating of the heat transfer member 21 is stopped. Further, compressed air is supplied to the slider driving air cylinder 36 so that the wedge block 3
5, the cooling member 23 is moved together with the slider 31 to the heat transfer member 21 side, and the cooling member 2
The rubber-like elastic body 41 of No. 3 is pressed against the heat transfer member 21. The cooling member 23 is supplied with the refrigerant from the refrigerant introduction pipe 39 and is discharged to the outside from the refrigerant discharge pipe 40 through the refrigerant passage.
The heat of the heat transfer member 21 is absorbed by the refrigerant via the heat transfer member 21, the heat transfer member 21 is efficiently cooled, the solder is rapidly solidified, and the lead portion 4 and the foot land 7 are integrally joined (FIG. 7).
reference). In this embodiment, the holding time for pressing the cooling member 23 against the heat transfer member 21 is set to 2 seconds.

The temperature of the heat transfer member 21 cooled by the cooling member 23 is measured by the thermocouple thermometer 27, and after the discriminating unit 28 confirms that the temperature is below a predetermined temperature, the heat transfer member driving air is cooled. The supply of compressed air to the cylinder 22 and the slider-driving air cylinder 36 is stopped, the heat transfer member 21 is pulled up from the lead portion 4 and brought into contact with the heating member 20, and heating of the heat transfer member 21 is restarted, while cooling is performed. The member 23 is detached from the heat transfer member 21, and one cycle of the soldering work is completed (see FIG. 8).

Thereafter, by repeating the above-mentioned operation, the soldering work between the foot land 7 of the printed wiring board 5 and the lead portion 4 of the electronic component is continuously performed.

[0031]

According to the soldering method and the apparatus thereof of the present invention, the cooling member is brought into contact with the heat transfer member and the heat transfer member is used to absorb the heat, so that the heat transfer member can transfer the heat more quickly than before. As a result of being able to cool the thermal member, solidification of the solder is accelerated, the time required for soldering is shortened, and soldering with high productivity becomes possible.

Here, when the cooling member has the casing and the refrigerant passage formed in the casing to supply the refrigerant, the cooling of the cooling member itself after absorbing the heat of the heat transfer member is accelerated, and the heat transfer member is cooled. Since the heat absorption is more efficiently performed, the time required for soldering can be further shortened.

When the portion of the cooling member that abuts against the heat transfer member is formed of a rubber-like elastic body, the rubber-like elastic body is elastically deformed in accordance with the pressing operation of the cooling member against the heat transfer member, so that the heat transfer member is formed. The contact state between the cooling member and the cooling member is improved, the contact area is expanded, the heat transfer member absorbs heat more efficiently, and the time required for soldering can be further shortened.

[Brief description of drawings]

FIG. 1 is a conceptual diagram showing a schematic structure of an embodiment of a soldering device according to the present invention.

FIG. 2 is an enlarged view in which a main part of FIG. 1 is extracted.

FIG. 3 is a sectional view taken along the line III-III in FIG.

4 is a sectional view taken along the line IV-IV in FIG.

FIG. 5 is a work process diagram showing an operation procedure of the soldering apparatus according to the present embodiment together with FIGS. 6 to 8;

FIG. 6 is a work process diagram showing an operation procedure of the soldering apparatus according to the present embodiment together with FIGS. 5, 7, and 8.

FIG. 7 is a work process diagram showing an operation procedure of the soldering apparatus according to the present embodiment together with FIGS. 5, 6 and 8.

FIG. 8 is a work process diagram showing an operation procedure of the soldering apparatus according to the present embodiment together with FIGS.

FIG. 9 is a perspective view showing the appearance of an example of a tape-shaped insulating film that houses electronic components to be soldered according to the present invention.

FIG. 10 is a perspective view showing the appearance of an example of a printed wiring board that is the subject of soldering according to the present invention.

FIG. 11 is a conceptual diagram showing a schematic structure of a conventional soldering device.

[Explanation of symbols]

 4 Lead Part 5 Printed Wiring Board 6 Solder Paste 7 Footland 11 Frame 12 Pin 13 Swing Lever 14 Elevating Head 15 Pin 16 Elevating Drive Motor 17 Ball Screw Shaft 18 Fitting Hole 19 Heater 20 Heating Member 21 Heat Transfer Member 22 Transmission Air member driving air cylinder 23 Cooling member 24 Female screw pin 25 Thermocouple thermometer 26 Temperature adjuster 27 Thermocouple thermometer 28 Discriminating unit 29 Controller 30 Guide pin 31 Slider 32 Arm part 33 Compression coil spring 34 Lid plate 35 Wedge block 36 Air cylinder for slider drive 37 Piston rod 38 Guide member 39 Refrigerant introduction pipe 40 Refrigerant discharge pipe 41 Rubber-like elastic body

Claims (4)

[Claims] 1. A step of bringing a heat transfer member into contact with a heating member incorporating a heater to raise the temperature of the heat transfer member, and pressing the heat transfer member receiving heat from the heating member against a soldering target portion, A step of melting the solder intervening in the soldering target portion; a step of separating the heating member from the heat transfer member pressed against the soldering target portion; and the heat transfer pressed against the soldering target portion. And a cooling member is brought into contact with the member, and the heat transfer member absorbs heat to cool the soldering target portion. 2. A heating member incorporating a heater and supported so as to reciprocate in a first direction with respect to a main body frame, a heating member drive means for driving the heating member in a first direction, and the heating member. A heat transfer member that can be in contact with the member, is pressed against the soldering target portion, and can reciprocate in the first direction with respect to the heating member; and a heat transfer member that drives the heat transfer member in the first direction. A member driving means, a cooling member that can contact the heat transfer member to cool the heat transfer member and that is reciprocally provided in a second direction intersecting the first direction; A soldering device comprising: a cooling member driving means that is driven in a second direction. 3. The cooling member has a casing and a refrigerant passage formed in the casing, and the refrigerant is supplied to the refrigerant passage. Soldering equipment. 4. The soldering device according to claim 2, wherein a portion of the cooling member that comes into contact with the heat transfer member is formed of a rubber-like elastic body.