JP2005101346A - Removing method of component mounted on printed circuit board - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide the removing method of a component mounted on a printed circuit board, which prevents damage to a printed circuit board upon removing an IC chip, and easily removes the component. <P>SOLUTION: A soldering jig 1 heats and melts solder 2 in a solder tank 3 to eject the solder 2. The printed circuit board 6 is disposed while opposing the component 7 mounted on the surface of the board 6 to the solder tank 3 of the soldering jig 1. In this case, a gap in the degree of not contacting with the solder 2 is provided which flows through the soldering part 9 of the component 7 mounted on the board. The soldering part 9 of the component 7 mounted on the board is heated by the heat of solder 2 which flows through the inside of the solder tank 3. The component 7 mounted on the board is extruded out of the printed circuit board 6 by penetrating a pushing rod 10 through the through hole 8 formed on the mounting part of the board mounting component 7 from the rear surface side of the board 6 before melting the solder 2 on the soldering part 9 to remove the same. <P>COPYRIGHT: (C)2005,JPO&NCIPI

Description

  The present invention relates to a method for removing a mounted component on a printed circuit board.

  Conventionally, the printed circuit board or the mounted component is reused by removing the mounted component on the printed circuit board. To remove the IC chip and other mounted components from the printed circuit board, the soldering part between the IC chip and the printed wiring of the printed circuit board is heated with a soldering iron having a flat iron tip to melt the solder and the IC. The tip is removed.

  In this method, among various IC chip types, an external output terminal is inserted into a hole for an external output terminal of an IC chip on a printed circuit board such as a DIP package or a PCA package, and soldered on the back surface of the printed circuit board. It is effective for things.

  However, in the case of a flat package where all of the external output terminals of the IC chip are soldered to the surface of the printed circuit board, the IC chip and other mounted parts are in the way, and the soldering iron contacts the soldered part of the IC chip. Difficult to do.

  In view of this, Patent Documents 1 and 2 disclose a removal apparatus and method for a flat package in which an IC chip is soldered to the surface of a printed circuit board. First, in Patent Document 1, a frame-shaped iron tip is brought into contact with a soldered portion of an IC chip, and the IC chip is adsorbed by a suction cup. In this state, the solder at the soldering portion of the IC chip is melted by the heat of the tip, and at the same time, the suction cup is pulled up to remove the IC chip.

In Patent Document 2, heating air is supplied to the soldering portion of the IC chip through a temperature control passage disposed so as to surround the suction pad, and the solder of the soldering portion is melted by the heating air. When the solder melts, it is removed by being pushed up with a pin in a direction away from the printed board through a hole formed at a position corresponding to the IC chip of the printed board.
JP-A-4-284968 (paragraphs 0005 to 0006, FIG. 1) JP-A-5-191036 (paragraphs 0007 to 0008, FIG. 1)

  By the way, even in the case of the flat package as described above, when removing the mounted component from the printed circuit board, it is required to remove the printed circuit board or the mounted component so that there is no damage or deterioration.

  However, in Patent Document 1, the frame-shaped soldering tip is brought into contact with the soldering portion on the printed circuit board side, so that the joint portion with the soldering tip on the printed circuit board is also heated, and the pad surface of the printed circuit board There are problems such as peeling of the solder, and conversely, the remaining amount of solder in the soldering portion adheres.

  In Patent Document 2, since the heating air is heated to a temperature at which the solder of the soldering portion is melted, the printed circuit board is also heated at the same time, and there is a problem that the surface deteriorates. Further, since the solder at the soldering portion is melted by the heating air, a heating time is required, and there is a problem that it takes time to remove the IC chip from the printed board.

  Therefore, the present invention prevents the peeling and deterioration of the pad surface of the printed circuit board, facilitates the removal of the printed circuit board mounted component such as an IC chip, and allows the printed circuit board to be reused. The purpose is to provide a method for removing

  In order to achieve the above object, a printed circuit board mounting component removing method according to the present invention is a method of removing a printed circuit board mounting component mounted on a surface of a printed circuit board by soldering. A through-hole formed in the mounting portion of the board mounting component from the back side of the printed circuit board by heating the soldering portion of the board mounting component by the heat of the solder jetted in the solder bath. A push rod is inserted into the board, and the board mounting component is pushed out of the printed board and removed.

  According to the above configuration, since the solder of the soldered portion of the board mounted component is heated and softened using the heat of the molten solder in the solder bath, and the board mounted component is removed by the mechanical pressing force of the push rod. The board-mounted component can be easily removed without heating the printed board more than necessary.

  At this time, when the printed circuit board is placed in the solder bath, a gap is formed so as not to come into contact with the solder jetted through the soldering portion of the board mounted component. As a result, the printed circuit board is not directly exposed to the jetted solder, so that damage or deterioration of the printed circuit board can be prevented.

  Using the solder jig, the board mounting parts are removed by the heat of the molten solder in the solder bath and the pressing force of the push-in rod, so that the printed board can be prevented from being damaged or deteriorated. Can be reused.

  Hereinafter, embodiments of the present invention will be described with reference to the drawings. FIG. 1 is a schematic view for explaining a method of removing a printed board mounting component according to the present invention using a solder jig, and FIG. 2 is an overall perspective view of the printed board shown in FIG.

  In the present invention, the mounting component 7 of the printed circuit board 6 is removed using the solder jig 1. As shown in FIG. 1, a solder jig 1 used in this method is heated by a solder bath 3 for filling solder 2, a heating device 4 for heating the solder 2 in the solder bath 3, and a heating device 4. It comprises a jet device 5 for jetting liquefied solder 2.

  The solder bath 3 is a container having an opening formed in a rectangular shape so as to surround the board mounting component 7. The solder bath 3 is filled with the solder 2 and is heated by the heating device 4. The solder 2 melted by the heating device 4 is jetted from the surface of the solder bath 3 by the jet device 5.

  The heating device 4 is composed of, for example, a sheathed heater in the solder bath 3. The solder 2 can be heated and melted to a predetermined temperature (255 ° C. to 265 ° C.) by the heating device 4 and its control unit (not shown), and can be kept at a constant temperature during the work of removing the board mounting component 7.

  The jet device 5 jets the solder 2 liquefied by the heating device 4 so as to rise on the surface of the opening of the solder bath 1. For example, the jet 2 is agitated and jetted with the solder 2 in the solder bath 3 with a blower or the like. Anything is fine.

  As shown in FIG. 2, the printed circuit board 6 has through holes 8 formed in the mounting portion of the printed circuit board 6 on which the substrate mounting component 7 is mounted. The through hole 8 is disposed at a substantially central portion of the size of the board mounting component 7, and the diameter varies depending on the size of the board mounting component 7. For example, as shown in Table 1, when the size of the board mounting component 7 is 20 mm × 14 mm, the diameter of the through hole 8 may be 4.0 mm.

基板搭載部品７は、フラットパッケージタイプのＩＣチップである。このＩＣチップ７は、プリント基板６上において他の部品との距離を約５ｍｍ以上あけて配置するのが好ましい。

The substrate mounting component 7 is a flat package type IC chip. The IC chip 7 is preferably arranged on the printed circuit board 6 with a distance of about 5 mm or more from other components.

  The push-in rod 10 is used to insert the through-hole 8 formed in the printed circuit board 6 and remove the board mounting component 7, and is a cylindrical pin formed of wood or resin. It is preferable that the push rod 10 has a diameter that can be inserted without being caught in the through hole 8 and has a large area in contact with the board mounting component 7. Further, when pushing out with the push-in rod 10, damage to the printed circuit board 6 such as pattern peeling does not occur when a force is applied to the board mounting component 7 with good balance. For example, if the diameter of the through hole 8 is 4.0 mm, the diameter of the push rod 10 is preferably 3.9 mm. The push rod 10 is not particularly limited to a cylindrical shape formed of wood, resin, or the like. The material and shape of the push rod 10 may be changed depending on the shape of the through hole 8.

  Next, a method for removing the IC chip 7 from the printed board 6 using the solder jig 1 will be described with reference to FIG.

  First, a flat package type IC chip 7 mounted on the surface side of the printed circuit board 6 is placed facing the solder tank 3. At this time, the printed circuit board 6 is placed so that the soldering portion 9 of the IC chip 7 is not in contact with the solder 2 jetted in the solder bath 3 and the IC chip 7 is surrounded by the solder bath 3. Put. After placing the printed circuit board 6 on the solder jig 1, the solder jig 1 is operated, and the solder 2 in the solder bath 3 is heated by the heating device 4 to make the solder 2 liquefied at a certain temperature, that is, a predetermined temperature (255 ° C.). To ˜265 ° C.). When the temperature of the solder 2 in the solder bath 3 rises to a certain temperature, the solder 2 in the solder bath 3 is jetted by the jet device 5 to heat the soldering portion 9 of the IC chip 7. The soldering portion 9 of the IC chip 7 is heated for a certain time (for example, 7 seconds), the pushing rod 10 is pushed through the through hole 8 formed in the printed board 6, and the IC chip 7 is removed from the printed board 6. The timing for pushing the push rod 10 into the through hole 8 is performed before the solder 2 of the soldering portion 9 of the IC chip 7 is melted. When the IC chip 7 is removed, the operation of the solder jig 1 is stopped and the printed circuit board 6 is collected. The heating of the soldering part 9 is stopped before the solder 3 is melted. Thereby, damage to the printed circuit board 6 can be prevented.

  As described above, in the above-described embodiment, it is possible to remove the IC chip from the printed board by operating the solder jig only within a predetermined time. That is, the working time can be shortened. Further, since the push rod is simply pushed into the through hole to remove the IC chip, the operation can be easily performed.

  Furthermore, by changing the diameter of the through-hole for the IC chip to be removed, it is easy to remove the IC chip because it can apply an equal force to the IC chip when it is pushed out from the back surface with the push-in rod. The load on the printed circuit board at the time of removal can also be suppressed, and damage or deterioration can be prevented.

Schematic for explaining a method of removing a mounted component of a printed circuit board according to the present invention using a solder jig Whole perspective view of the printed circuit board shown in FIG.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Solder jig 2 Solder 3 Solder tank 4 Heating apparatus 5 Jet apparatus 6 Printed circuit board 7 Board mounting component (IC chip)
8 Through hole 9 Soldering part 10 Push rod

Claims (4)

In the method of removing the board mounting component mounted on the surface of the printed board by solder, the board mounting part on the surface side of the printed board faces the solder bath of the solder jig, and the board is heated by the heat of the solder jetted in the solder bath. The soldering part of the mounting component is heated, and a push rod is inserted through the through hole formed in the mounting part of the board mounting component from the back side of the printed circuit board, and the board mounting component is pushed out of the printed circuit board and removed. A method for removing printed circuit board mounting parts characterized by the above. The board mounting component is placed with a gap so as not to contact a solder jetted in the solder bath when the board mounting component faces a solder bath of a solder jig. Item 8. A method for removing a printed circuit board mounting component according to Item 1. 3. The method of removing a printed circuit board mounting component according to claim 1, wherein the operation of pressing the board mounting component with the pressing rod is performed before the solder of the soldering portion of the substrate mounting component is melted. The method for removing a printed board mounted component according to claim 1, wherein the board mounted component is an IC chip.

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