KR20070089311A - Electronic circuit board repair device - Google Patents

Abstract

An electronic circuit board repair device is provided to prevent electronic parts and a circuit board from being damaged by radiating sufficient infrared rays to the electronic parts and preventing the thermal diffusion of the electronic parts. An electronic circuit board repair device includes a heating unit, an infrared ray irradiating device mounted to ascend/descend along a guide unit such as a guide rail provided in a vertical base(2) in a vertical direction. In addition, the infrared ray irradiating device is configured to ascend and descend by a lifting unit along the guide unit at an upper side of a horizontal base(1). The lifting unit includes a servo motor(11) connected to an encoder(10), and the infrared ray irradiating device is connected to the servo motor(11) by a connecting unit to move by the operation of the servo motor(11) along the guide unit of the vertical base(2) in a vertical direction. The infrared ray irradiating device and a vacuum bit(12) ascend/descend at the upper side of the horizontal base(1).

Description

Electronic circuit board repair device

Figures 1 (a) and 1 (b) show an embodiment of the apparatus according to the invention, respectively, with the cover closed and with the cover open;

2 is a block diagram showing an embodiment of the apparatus according to the present invention;

3 (a) to 3 (c) are enlarged cross-sectional views, top views, and thermometer measurement points each showing an embodiment of a load cell constituting an apparatus according to the present invention.

4 is a view showing an embodiment of an infrared irradiation device constituting the device according to the present invention in the vicinity of the vacuum bit;

5 is a perspective view showing one embodiment of the infrared irradiation limiting means constituting the apparatus according to the present invention;

6 is a view showing an embodiment of an infrared irradiation device constituting the device according to the present invention in the vicinity of the vacuum bit;

7 is a perspective view showing one embodiment of the infrared irradiation limiting means constituting the infrared irradiation device of the apparatus according to the present invention;

8 is a view showing another embodiment of an electronic circuit board repair apparatus to which the infrared irradiation device of the present invention is applied.

9 is a perspective view showing another embodiment of the infrared irradiation limiting means;

<Explanation of symbols for the main parts of the drawings>

6. Infrared irradiation device 12. Vacuum bit

13, 13 ', 13 ", infrared source 14. Vacuum pipe

15. Load Cell 16, 16 ', 16 ", 18. Thermocouple

23. Control device 40. Infrared radiation limiting means

41. Transmission window 42. Infrared shield window

42a. Through Hole 50. Hood

51. Gas supply port 52. Outlet

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an apparatus for soldering electronic components to circuit boards or for separating components soldered to circuit boards.

In general, in the case of mounting an IC on a printed circuit board, the soldering apparatus is, for example, as shown in Japanese Patent Application Laid-Open No. 8-46351 (Patent Document 1) and Japanese Patent Publication (Patent Document 2). The IC is adsorbed to the vacuum bit formed at the tip of the elevable hot air spray device, dropped on the corresponding conductive pattern on the printed circuit board coated with cream solder, and then heated by spraying the hot air controlled at a constant temperature through the nozzle. It is configured to.

In addition, the separation of the IC soldered to the printed circuit board is performed by contacting the nozzle with the IC on the substrate, heating the substrate, and adsorbing the vacuum bit in the nozzle to separate the substrate from the substrate.

However, when hot air is used as a heating means, in microelectronic components such as CSP (chip size package) and micro ball grid array (BGA), it is impossible to uniformly heat the surface, causing variation in the surface temperature. There is a problem that the inside of the apparatus (bonding region) is simply broken by the thermal expansion difference at the time of heating.

In addition, since air having a significantly low thermal conductivity and ratio are used for the heat transfer medium, it is necessary to supply a large amount of heating air in a unit time, and it is difficult to recover solder-derived contaminants generated during heating.

In addition, the hot air leaking from the hot air supply nozzle may separate and damage the electronic parts adjacent to the soldering part. If the exhaust duct is provided to completely shield the hot air and exhaust it to the upper side, it is remarkable between the electronic parts. A large gap is required, resulting in a printed board not applicable.

In order to solve the problem of the apparatus which uses such a hot air as a heating medium, as shown in Unexamined-Japanese-Patent No. 5-315739 (Patent Document 3) and Unexamined-Japanese-Patent No. 5-102654 (Patent Document 4) It is also conceivable to use a device with a heat source, and since these devices are intended for an electronic component provided with a soldering region (lead portion) on the side of the component main body, the backside (backside) of the main body is a soldering region. It cannot be said that it can be applied to electronic components such as CSP and micro BGA.

SUMMARY OF THE INVENTION The present invention has been made in view of the above problems, and an object thereof is to selectively solder an electronic component and to uniformly heat the target electronic component, whereby soldering or separation from a circuit board can be performed while suppressing thermal stress as much as possible. An electronic circuit board repair apparatus is provided.

In order to achieve the above object, the present invention provides a vacuum bit for sucking an electronic component, heating means for irradiating infrared rays in the vicinity of the vacuum bit, elevating means for elevating the vacuum bit and the heating means, and at least electrons. Temperature detecting means for detecting the surface temperature of the component, and infrared irradiation limiting means disposed below the heating means to limit the infrared rays from the heating means to increase the temperature of the electronic component and the circuit board of the electronic component; And heating the soldering region of the electronic component to the melting temperature of the solder while heating the circuit board around the electronic component.

Hereinafter, the present invention will be described in more detail with reference to Examples. 1 (a) and 1 (b) show an embodiment of an electronic circuit board repair apparatus according to the present invention, respectively, and includes a horizontal base 1 and a vertical base 2, wherein the horizontal base 1 The XY table 3 which sets the planar position of the circuit board P is provided, and the slide covers 4 and 5 are provided in the upper part of the table 3.

On the other hand, the vertical base 2 is provided with an infrared irradiation device 6, a touch panel display 7, and an emergency stop command switch 8.

Figure 2 shows an overview of an electronic circuit board repair apparatus according to the present invention, the heating means, that is, the guide means such as a guide rail (not shown) installed in the vertical direction 2 in the vertical direction (2) It is mounted to be elevated along. In addition, the infrared irradiation device 6 is configured to be lifted from the upper side of the horizontal base 1 along the guide means by the lifting means. That is, the lifting means is composed of a servo motor 11 connected to the encoder 10, the infrared irradiation device 6 is connected to the servo motor 11 by a connecting means (not shown), the servo motor 11 Since it moves in the vertical direction along the guide means of the vertical base (2) by the operation of the heating means (that is, the infrared irradiation device 6) and the vacuum bit 12 to be described later is raised and lowered above the horizontal base (1) Can be.

The infrared irradiation device 6 is detachably mounted to the lower end of the vacuum bit 12 which adsorbs the electronic component by negative pressure, and infrared generating means for irradiating infrared rays to the tip region of the vacuum bit 12 ( 13), a vacuum pipe 14 for supplying a negative pressure to the vacuum bit 12, a load cell 15 for supporting the upper portion of the vacuum pipe 12, detecting the pressure acting on the vacuum bit 12, and The temperature detecting means, in this embodiment, is configured to accommodate a thermocouple 16.

The load cell 15 has a vacuum in the center of the elastic plate having a support 30, which is elastically deformable in the vertical direction, in this embodiment a cross-shaped branching portion 31, while preventing the swing in the horizontal plane as shown in FIG. The pipe 14 is fixed by passing through it, and the strain gauge 32 is attached to the branch part 31, and is comprised.

In addition, the thermocouple 16 penetrates the two thermocouple wires 34 and 35 from the upper end to the lower end of the vacuum pipe 14, and the electronic component D supported by the vacuum bit 12 as shown in FIG. 4. It is formed by forming a thermal contact in contact with the upper surface of the.

In addition, the temperature detection point 16a makes contact with the electronic component D through the heat-resistant thermal conductive adhesive S, for example, silicon grease, as shown in FIG. 3 (c), thereby accurately adjusting the temperature of the electronic component to be heated. Can be detected.

The irradiation area limiting means 40 described later is disposed so as to surround the vacuum bit 12. Below the vacuum bit 12, an image pickup device 17 for photographing the back surface of the semiconductor device D held by the vacuum bit 12 and the surface of the circuit board P is disposed so as to be able to move forward and backward. . This imaging device 17 includes a beam splitter, a light emitting element arranged in a rectangular shape, and an image pickup element, as shown in Japanese Patent Laid-Open No. 7-115300. It converts into an electrical signal by this.

If necessary, the back surface of the circuit board P is placed between the back surface of the XY table 3 and the base 1 at a position opposite to the vacuum bit 12 on the back surface of the circuit board P. The infrared irradiation device which heats is arrange | positioned.

5 shows an embodiment of the above-described infrared irradiation limiting means 40, which partitions the transmission window 41 into a size substantially equal to the photographing surface of the electronic component D to be soldered or separated. The infrared shielding wall 42 is provided, and the infrared shielding wall 42 is provided with a plurality of through holes 42a so as to surround the periphery of the transmission window 41.

These through-holes 42a are irradiation holes for irradiating infrared rays for auxiliary heating of the circuit board P around the electronic component D to be mounted or separated, and to unnecessarily heat other electronic components. It is formed so that it may become a density which can suppress heat dissipation as much as possible from the target electronic component.

More preferably, as shown in FIGS. 6 and 7, an inert gas supply means, that is, a hood 50, is disposed around the electronic component at the tip of the irradiation limiting means 40. An electronic component that is subjected to at least mounting or separation by inert gas such as nitrogen heated by the inert gas heated at the lower end of the hood 50 by being heated by the inert gas heated at the lower end of the hood 50. It is comprised so that (D) may be surrounded.

The process of soldering and separating electronic components by the present invention will be described.

First, the heating profile suitable for the electronic component D to be soldered by the touch panel 7 is set by the setting button, or the data of the heating profile registered in advance is called out. When the electronic component D to be hot air soldered is conveyed to the predetermined position by the part feeder 20, the distance between the base of the part feeder 20 and the surface of the electronic component D by the laser distance measuring device 21. L1 and L2 are measured to detect the thickness L1-L2 of the electronic component D. FIG.

Subsequently, the parts feeder 20 conveys the electronic component D directly under the vacuum bit 12 to be supported by the vacuum bit 12. In this state, as shown in FIG. 2, the thermal contact of a thermocouple contacts the surface of the electronic component D, and the surface temperature of the electronic component D is input to the control apparatus 23 as a signal.

Next, the centering device (not shown) is moved to regulate the relative position between the vacuum bit 12 and the electronic component, and the XY table 3 is moved to move the predetermined conductive pattern of the circuit board P into the vacuum bit 12. Move it underneath. In addition, the centering device can be constructed by elastically supporting a pawl for regulating four sides of an electronic component by an elastic support means as shown in JP-A-5-48299, for example. have.

At this time, if necessary, the imaging device 17 is moved to this area, and an image of the bottom surface of the electronic component D and the conductive pattern of the circuit board P is synthesized by a half mirror to form an image of the touch panel 7. By mirroring the display area 50, the position of the XY table 3 is finely adjusted by a microscopic device (not shown).

When the position adjustment is completed, when the covers 4 and 5 are closed and the button is pressed, the servomotor 11 operates at high speed so that the infrared irradiation device 6 descends, and the height thereof is detected by the encoder 10. . In the step of descending to the predetermined position, the servomotor 11 rotates at low speed and continues to fall further. When the bottom surface of the electronic component D contacts the circuit board P, a reaction force acts on the vacuum pipe 14 to output a load signal from the load cell 15. When the load reaches a predetermined value, for example, 0.1 g, the servomotor 11 is stopped. As a result, the electronic component D is positioned at a pressure suitable for soldering to the circuit board P. FIG.

Subsequently, when the heating command is issued by the touch panel 7, the temporal change of the temperature detected by the thermal contact in contact with the surface of the electronic component D is brought to the infrared source 13 so as to be in a preset state. Supply power is controlled.

The infrared rays (arrows in FIG. 4) from the infrared ray source 13 pass through the irradiation window 41 of the infrared irradiation limiting means 40 to heat the electronic component D from the upper surface, and simultaneously pass through the through hole 42a. The transmitted infrared rays heat the circuit board P around the electronic component mounting area.

In this way, the solder on the back surface of the electronic component can be rapidly heated to the melting temperature while suppressing the heat conduction from the electronic component D heated by infrared rays to the circuit board as much as possible.

When the electronic component (D) and the circuit board (P) accompanying the heating are thermally expanded and the reaction force (pressure) to the vacuum bit 12 increases, the load of the load cell 15 also increases through the vacuum pipe 14. Therefore, the servomotor 11 is reversed to keep the pressing force of the electronic component D constant.

As a result, since the electronic component D is always pressurized to the circuit board P at a constant pressure, it is possible to prevent the electronic component D from being damaged or a short circuit due to solder cracking. In this way, the supply of power to the infrared source 13 is stopped when the solder cream applied to the circuit board P or the solder particles of the electronic component D are melted, and the servomotor 11 at the time when the solder is solidified. ) Is reversed and the infrared irradiation device 6 is raised to return to its original position.

At the time of soldering, if necessary, auxiliary heating is performed by controlling the back temperature of the circuit board P by the lower heater, whereby overheating of the electronic component D can be prevented and soldering can be performed reliably.

On the other hand, in the case where the electronic component D soldered to the circuit board P is removed for exchange, the infrared irradiation device 6 is dropped in the step of adjusting the position so that the vacuum bit 12 is removed. Contact (D) with a predetermined load.

Then, the power supply to the infrared ray source 13 is controlled so that the temperature of the electronic component D rises in a prescribed time pattern, and the solder holding the electronic component D is melted. Subsequently, when the servomotor 11 is reversely driven, the electronic component D is held by the vacuum bit 12 to be separated from the circuit board P.

In this separation, as described above, the infrared rays (arrows in FIG. 4) from the infrared source 13 pass through the irradiation window 41 of the infrared irradiation limiting means 40 to heat the electronic component D from the upper surface. At the same time, the infrared rays transmitted through the through hole 42a heat the circuit board P around the electronic component mounting area. Thereby, the solder on the back surface of the electronic component can be rapidly heated to the melting temperature while suppressing the heat conduction from the electronic component D heated by infrared rays to the circuit board as much as possible.

In addition, when a negative load signal is output from the load cell 15, it means that unmelted solder is present, so the servomotor 11 is rotated forward to reheat the solder. Thereby, the electronic component can be separated safely and reliably without exerting an excessive load on the electronic component D or the circuit board P.

Fig. 8 shows another embodiment of the present invention. In this embodiment, the infrared auxiliary heating means 13 ', 13 " for heating from the outside / inside of the circuit board in the outer peripheral area of the infrared irradiation device 6 are shown. Are designated. In the drawings, reference numerals 14 'and 14 "denote thermocouples.

According to this embodiment, even if the electronic component D is small in size and heat dissipation is large, the solder on the back surface of the circuit board is kept as small as possible, while the temperature difference between the electronic component and the surroundings is kept as small as possible. Can be efficiently performed in a short time to be heated to a predetermined temperature.

In addition, in the present invention, the same effect can be applied to not only a semiconductor device but also a smaller electronic component such as a resistor.

In addition, although the temperature of an electronic component or a circuit board is measured by the thermocouple in the Example of this invention, even if a resistance temperature measuring element or an infrared sensor is used, it exhibits the same effect.

In addition, in the above-described embodiment, the infrared irradiation limiting means forms a through hole in the plate and emits the radiation while limiting the infrared rays for heating the circuit board, as shown in FIG. 41 '), the radiation window 41' emits sufficient infrared rays to heat the electronic component, and the filter plate around the substrate prevents heat dissipation around the electronic component of the circuit board. It can emit infrared light.

As described above, according to the present invention, while supplying sufficient infrared rays to the area of the electronic component to melt the solder, heat dissipation of the heated electronic component can be prevented while surrounding circuit boards are damaged at the same time. Since infrared rays can be selectively supplied to each other so as not to be damaged, there is an advantage of preventing damage to electronic components and circuit boards. In addition, since there is no wind pressure acting on the electronic component as in the case of heating by hot air, stable soldering can be performed.

Claims (4)

A vacuum bit 12 for sucking electronic components, heating means 13 for irradiating infrared rays in the vicinity of the vacuum bit, elevating means 11 for elevating the vacuum bit 12 and the heating means 13; Arranged below the table 3 supporting the supplied circuit board P and moving in the horizontal direction, the temperature detecting means 16 for detecting the surface temperature of the electronic component D, and the heating means 6. And infrared irradiation limiting means (40, 40 ') for limiting infrared rays to the heating means (13) so that the temperature of the electronic component (D) and the circuit board (P) is increased. An apparatus for repairing an electronic circuit board, comprising heating the soldering region of the electronic component (D) to the melting temperature of the solder while heating the circuit board (P) around the component (D). The infrared radiation limiting means (40) according to claim 1, wherein the infrared radiation limiting means (40) forms an infrared transmission window (41) in a region corresponding to the electronic component (D), and a through hole for infrared limiting around the infrared transmission window (41). Electronic circuit board repair apparatus, characterized in that formed by (42a). 2. The infrared radiation limiting means (40 ') is formed by an infrared absorption filter plate (40') having an infrared transmission window (41 ') formed in a region corresponding to the electronic component (D). Electronic circuit board repair apparatus. The electronic circuit board according to any one of claims 1 to 3, further comprising an inert gas supply means (50) for supplying an inert gas heated around the electronic component (D). Repair device

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