JP4454549B2 - Circuit board mounting and joining method - Google Patents

Description

  The present invention relates to a method for mounting and joining circuit boards made of FPC, PCB (printed circuit board) or the like.

A flexible printed circuit board (FPC) used in the fields of electricity, electronics, communication, etc. is mounted with a plurality of electronic components such as capacitors, resistance elements, ICs, LSIs, etc. Moreover, since it is thin, it is difficult to put it alone into the component mounting line.
In view of this point, conventionally, it is temporarily fixed on a hard carrier (not shown) via an acrylic double-sided adhesive tape, and is put into the component mounting line in this temporarily fixed state, followed by reflow soldering. (See Patent Document 1).
JP 2002-338916 A

  Conventional flexible printed circuit boards are simply temporarily fixed on a carrier as described above, but although the carrier is hard, acrylic double-sided adhesive tape lacks heat resistance and cannot be used repeatedly. There's a problem. Further, when temporarily fixed on the carrier, since it is a manual operation, the pressing force acts non-uniformly, and there is a problem that a good temporarily fixed state cannot be obtained.

  The present invention has been made in view of the above, and an object of the present invention is to provide a circuit board mounting and joining method that can be used repeatedly and can obtain a good temporarily fixed state.

In order to solve the above-mentioned problems in the present invention, circuit board mounting joining using a positioning jig in which a plurality of positioning pins protrude from the surface and a carrier jig that detachably holds a thin circuit board on the adhesive layer. A method,
The circuit board is positioned and arranged on the positioning jig via a plurality of positioning pins, and the carrier jig is stacked (stacked) on the positioning jig via the plurality of positioning pins, and the carrier jig adhesive layer is placed on the circuit board. It is characterized by sticking, removing the positioning jig and pulling it away from the circuit board, and then removing the circuit board on which electronic components are mounted from the carrier jig.

Solder is applied to the circuit board that is adhesively held on the adhesive surface of the carrier jig, electronic components are mounted on the circuit board that is adhesively held on the adhesive layer of the carrier jig, and the solder on the circuit board is melted (heated) It is preferable that the electronic components are soldered by melting them.
A circuit in which a carrier jig is stacked via a plurality of positioning pins on a separation jig in which a plurality of positioning pins and separation pins protrude from the surface, and an electronic component is mounted from the carrier jig by the plurality of separation pins. It is preferable to push up and remove the plate.

  Here, the thin circuit board in the claims includes at least one FPC, PCB, high-density flexible substrate, and the like. The circuit board is not particularly limited to flexibility, single-sided board, double-sided board and the like. When the circuit board is positioned and arranged on the positioning jig, one circuit board may be arranged, or the circuit boards may be arranged in a matrix of 1 × 2, 1 × 3, 2 × 2, etc. Further, a plurality of circuit boards may be detachably stacked and arranged in a matrix of 1 × 2, 2 × 2, 2 × 3, etc. in this stacked state.

  Electronic components include at least passive components made up of a plurality of capacitors and resistance elements, and active components made up of ICs, LSIs, photodiodes, etc. that have a low withstand voltage and are sensitive to static electricity. Furthermore, it is preferable that the separation jig, the positioning pin, and / or the separation pin are provided with electrical conductivity and are grounded to be subjected to electrostatic countermeasures.

According to the present invention, the carrier jig can be used repeatedly even in a process where heat acts strongly, and the circuit board can be favorably temporarily fixed.
Also, solder is applied to the circuit board that is adhesively held on the adhesive layer of the carrier jig, electronic components are mounted on the circuit board that is adhesively held on the adhesive layer of the carrier jig, and the solder on the circuit board is melted. Since the electronic parts are soldered, high-density mounting can be achieved without contamination of impurities, and minute portions can be joined substantially accurately and efficiently.

  In addition, a carrier jig is stacked via a plurality of positioning pins on a separation jig in which a plurality of positioning pins and separation pins protrude from the surface, and a circuit in which electronic components are mounted from the carrier jig by the plurality of separation pins. Since the board is pushed up and removed, it is possible to suppress or prevent the circuit board from being broken or contaminated manually.

  Hereinafter, a preferred embodiment of the present invention will be described with reference to the drawings. In the circuit board mounting and joining method according to the present embodiment, a plurality of positioning pins 2 are projected from the surface as shown in FIGS. The positioning jig 1, the carrier jig 20 that detachably holds the flexible flexible printed circuit board 10 on the adhesive layer 21, and the plurality of positioning pins 2 and separation pins 32 that protrude from the surface are electrically conductive. Various electronic components 12 are mounted and joined to the insulating flexible printed circuit board 10 by using a separable separating jig 30.

  As shown in FIG. 1 and the like, the positioning jig 1 is formed into a flat rectangular plate having at least a flat surface using, for example, a hard material, and cylindrical positioning pins 2 stand up at the four corners of the surface. The four corners of the flexible printed circuit board 10 and the carrier jig 20 are detachably fitted into the plurality of positioning pins 2.

  As shown in FIGS. 1, 3, 6, 7, etc., the flexible printed circuit board 10 is formed thinly and lightly using, for example, a polyimide film, copper foil, copper-clad laminate, etc. The positioning holes 11 are formed so as to be slightly smaller than the surface, and the positioning holes 11 penetrating through the positioning pins 2 of the positioning jig 1 are respectively drilled in the four corners.

  As shown in FIGS. 2 and 4, the carrier jig 20 is formed into a flat rectangular plate having at least a flat surface using a material such as a metal such as aluminum or glass epoxy, and the surface of the positioning jig 1. And a heat-resistant adhesive layer 21 for adhering and holding the opposing flexible printed circuit board 10 in a detachable manner is bonded to a flat surface. The carrier jig 20 has a plurality of rectangular through holes 23 formed on the surface thereof to avoid contact with an alignment hole 22 for removing the flexible printed circuit board 10 and a terminal portion of the flexible printed circuit board 10. Each of the positioning holes 24 penetrating through the positioning pins 2 of the positioning jig 1 is rounded.

  The adhesive layer 21 is made of, for example, silicone, fluoro rubber, acrylic rubber, polyimide silicone, urethane rubber, etc., and the adhesive surface is formed on the weak adhesive surface 25 by mirror finishing, and is adhered to the surface of the carrier jig 20. The layers are bonded via the reinforcing layer. The adhesive layer 21 is preferably conductive from the viewpoint of preventing electrostatic breakdown, but may be insulating. The adhesive layer is formed into a film shape having a thickness of 500 μm or less, for example, with an uncured silicone resin. The reinforcing layer may be formed into a film shape having a thickness of 50 μm or less using, for example, a resin film, a metal thin film, a glass cloth, or the like.

  As shown in FIGS. 8 to 10, the separation jig 30 is formed into a flat polygonal plate having a flat surface at least using a metal such as aluminum or a material such as glass epoxy, and is formed at the four corners of the surface. The positioning pins 31 that detachably pass through the positioning holes 24 of the carrier jig 20 are erected and protruded, and a plurality of separation pins 32 that penetrate the alignment holes 22 of the carrier jig 20 are formed on the surface. The protrusions are arranged side by side at a predetermined interval. The separation pin 32 is formed lower than the cylindrical positioning pin 31 using a conductive material, has a tip that is curved in a substantially hemispherical shape, and is grounded with a low impedance in order to obtain a ground potential. .

  In the above, when mounting and joining a plurality of various electronic components 12 to the flexible printed circuit board 10, first, the flexible printed circuit board 10 is positioned and arranged on the surface of the positioning jig 1 from above via the plurality of positioning pins 2 ( 1), and a carrier jig 20 that is turned upside down on the surface of the positioning jig 1 is uniformly pressed down from above via a plurality of positioning pins 2 (see FIG. 3), and the flexible printed circuit board 10 The weak adhesive surface 25 of the adhesive layer 21 is adhered to the back surface of the adhesive layer 21, the positioning jig 1 is removed downward, and is separated from the flexible printed circuit board 10 and the carrier jig 20 (see FIG. 5).

  Next, the carrier jig 20 is reversed so that the flexible printed circuit board 10 that is adhesively held on the adhesive layer 21 faces upward (see FIG. 6), and reflow solder is applied to the surface of the flexible printed circuit board 10 by screen printing or the like. The plurality of electronic components 12 are mounted on the flexible printed circuit board 10 by a mounter (see FIG. 7).

  After mounting the electronic component 12 in this way, the carrier jig 20 holding the flexible printed circuit board 10 is set in a conveyor type reflow machine (not shown) and heated to melt the reflow solder of the flexible printed circuit board 10 in a hot atmosphere. The electronic component 12 is soldered and cooled and removed downstream of the reflow machine. At this time, since hot air is blown from the reflow machine to the flexible printed circuit board 10, the flexible printed circuit board 10 is inevitably charged with friction with the hot air.

  Thereafter, the carrier jig 20 is laminated on the surface of the separation jig 30 from above via a plurality of positioning pins 31 (see FIG. 8), and the grounded separation pin 32 and the alignment hole 22 of the carrier jig 20 When the separation pin 32 is pressed into contact with the flexible printed circuit board 10 mounted on the surface of the electronic component 12 and the flexible printed circuit board 10 is pushed up by the separation pin 32 and peeled off (see FIG. 9) A series of operations for mounting and joining the plurality of electronic components 12 to the circuit board 10 is completed.

  According to the above, since the heat-resistant adhesive layer 21 is used instead of the acrylic double-sided adhesive tape lacking in heat resistance, the carrier jig 20 can be repeatedly used in a reflow process where heat acts strongly. Through this, workability and convenience can be remarkably improved, and running costs can be greatly reduced. Further, since the carrier jig 20 is uniformly crushed from above on the surface of the positioning jig 1 and the adhesive layer 21 is adhered to the flexible printed circuit board 10 from above, flexible printing can be performed without using a dedicated jig. The applied pressure can be applied uniformly to the circuit board 10, and a good temporarily fixed state can be easily obtained through this.

  In addition, the flexible printed circuit board 10 is pushed up by a plurality of separation pins 32 instead of hands or tweezers and peeled off from the carrier jig 20, so that workability and convenience are improved, and the flexible printed circuit board 10 is contaminated and damaged. Effective suppression can be prevented. Further, since the separation pin 32 of the separation jig 30 is grounded from the viewpoint of preventing electrostatic breakdown, the charged flexible printed circuit board 10 is discharged along with the peeling from the carrier jig 20, and as a result, the electronic component 12 is discharged. Can be very effectively prevented from being damaged or destroyed by the discharge of electric charge. Furthermore, since the electronic component 12 is subjected to reflow soldering, it can be mounted at a high density without being contaminated with impurities, and minute portions can be joined accurately and efficiently.

  Next, FIG. 11 shows a second embodiment of the present invention. In this case, all or a part of the positioning pins 31 of the separation jig 30 are notched in the longitudinal direction in the radial direction. A split pin that can be expanded and contracted is formed, and the tip portion that is cracked and spreads outward slightly is closely fitted in the positioning hole 24 of the carrier jig 20, and the positioning pin 31 is also grounded. The other parts are the same as those in the above embodiment, and the description thereof is omitted.

  In the present embodiment, the same effect as that of the above embodiment can be expected, and the positioning pin 31 that has been split pins is in close contact with the positioning hole 24 of the carrier jig 20, so that the charged carrier jig 20 can be charged. Clearly, it can be reliably dropped to GND and electrostatic breakdown can be more reliably prevented.

  In the above embodiment, the positioning pins 2 protrude from the four corners of the positioning jig 1. However, the present invention is not limited to this, and a plurality of positioning pins 2 protrude from the peripheral edge of the positioning jig 1. You may do it. Further, a plurality of positioning holes 11 may be drilled in the peripheral edge instead of the four corners of the flexible printed circuit board 10, or a plurality of positioning holes 24 may be drilled in the peripheral edge of the carrier jig 20.

  In addition, the adhesive layer 21 is bonded to the carrier jig 20 via the adhesive layer and the reinforcing layer. However, the adhesive layer 21 is not limited to this, and can be directly bonded to the surface of the carrier jig 20. Moreover, you may make it an operator adhere | attach the single or several adhesion layer 21 on the surface of the carrier jig | tool 20 as needed. Furthermore, if the electrostatic breakdown of the electronic component 12 can be prevented, the separation jig 30 can be provided with conductivity and grounded, and the positioning pins 31 and the separation pins 32 can be provided with insulation. is there.

1 is an overall perspective view showing an embodiment of a circuit board mounting and joining method according to the present invention. It is a perspective explanatory view showing a carrier jig in an embodiment of a circuit board mounting and joining method according to the present invention. It is a perspective explanatory view showing a state where a carrier jig is laminated from above on a positioning jig in an embodiment of a circuit board mounting and joining method according to the present invention. It is a section explanatory view showing a carrier jig in an embodiment of a circuit board mounting joining method concerning the present invention. It is a perspective explanatory view showing the state where the positioning jig in the embodiment of the circuit board mounting and joining method according to the present invention is removed and pulled away from the carrier jig. FIG. 6 is a perspective explanatory view showing a state where the carrier jig of FIG. 5 is reversed. FIG. 7 is an explanatory perspective view showing a state where electronic components are mounted on the carrier jig of FIG. 6. It is a perspective explanatory view showing the state where it laminates from above via the carrier jig in the embodiment of the circuit board mounting and joining method according to the present invention. FIG. 9 is an explanatory perspective view showing a state in which the flexible printed circuit board of FIG. 8 is pushed up by a separation pin and peeled off. It is a section explanatory view showing a separation jig in an embodiment of a circuit board mounting joining method concerning the present invention. It is a section explanatory view showing a separation jig in a 2nd embodiment of a circuit board mounting joining method concerning the present invention.

Explanation of symbols

1 Positioning jig 2 Positioning pin 10 Flexible printed circuit board (circuit board)
11 Positioning hole 12 Electronic component 20 Carrier jig 21 Adhesive layer 22 Alignment hole 23 Through hole 24 Positioning hole 30 Separating jig 31 Positioning pin 32 Separating pin

Claims (3)

A circuit board mounting and joining method using a positioning jig in which a plurality of positioning pins protrude from the surface and a carrier jig that detachably holds a thin circuit board on an adhesive layer,
Positioning and positioning the circuit board on the positioning jig via a plurality of positioning pins, laminating the carrier jig on the positioning jig via the plurality of positioning pins, and adhering the adhesive layer of the carrier jig to the circuit board, A circuit board mounting and joining method, comprising: removing a positioning jig and pulling the circuit board away from the circuit board, and then removing the circuit board on which the electronic component is mounted from the carrier jig.   Solder is applied to the circuit board that is adhesively held on the adhesive surface of the carrier jig, electronic components are mounted on the circuit board that is adhesively held on the adhesive layer of the carrier jig, and the solder on the circuit board is melted to electronic components. The circuit board mounting and joining method according to claim 1, wherein the circuit board is soldered. A carrier jig is laminated via a plurality of positioning pins on a separation jig in which a plurality of positioning pins and separation pins protrude from the surface, and a circuit board on which electronic components are mounted from the carrier jig by the plurality of separation pins. The circuit board mounting and joining method according to claim 1 or 2, wherein the circuit board is mounted by being pushed up and removed.

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