JPS6130096A - Method of securing printed board in chamfering device - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

Detailed Description of the Invention (A) Industrial Application Field The present invention is a deburring method for printed circuit boards that automatically removes burrs on leads of printed circuit boards that are generated when cutting the excess lead length of components mounted on printed circuit boards. It is related to the device.

In general, parts mounted on printed circuit boards are manufactured with sufficiently long leads and extra length to ensure versatility. Then, the leads are inserted into the through-holes of the printed board, the printed board is mounted on the carrier, and the protruding sides of the leads of the mounted components are isolated into the solder bath and connected to the through-holes.

The soldering process for such a printed circuit board consists of a plurality of steps. An example is shown in FIG.

In the figure, 20 is a carrier for conveying the printed board, and 21, which is shown in a shaded area, is a printing section. The printed board 21 on which lead components such as resistors and capacitors are mounted is placed in the carrier 2 for transporting the printed board 21 at the input section A in the figure.
It will be listed on 0.

Then, at B, Fura-7x is applied to facilitate soldering between the lead components and the printed circuit board wiring pattern. This is called the pre-flux ball level.

The printed circuit board coated with flux is heated at C. This is called the pre-heater process.

Thereafter, soldering is performed in step Te. This is called the solder depth process. In this case, since the leads of the lead component are made longer, an extra lead length portion is generated on the back surface of the printed board 21. The length of this extra lead length is standardized, so the extra lead length is cut at E to match the standard. The excess length of the lead is simply cut with a cutter, which inevitably causes lead burrs. The lead burrs on the back surface of the printed board are removed in the deburring step F, and the process proceeds to the cleaning step G. The cleaned printed board 21 is discharged from the printed board soldering line at the output section H, and the series of soldering processes is completed. The vacant carrier 20 returns again to the mounting position of the printed board 21 in the A input section. In the manner described above, the lead components mounted on the printed board are soldered. In the lead cutting step E of these soldering steps, as shown in the side view of FIG. The cutter 500 is held between the upper surface of the rotating disc-shaped cutter 500 and the lower surface of the printed board 1 and transferred, thereby cutting the excess length of the lead 300 of the mounted component 200.

However, as shown in FIG.
It is often attached to the tip of the lead 300 in a bent state. Furthermore, lead 30 as in (c)
An edge 400' (lead firmness) is formed at the tip of the lead.

Such lead burrs 400 may come into contact with adjacent patterns on the printed board 1 and cause a short circuit, and may fall off after the printed board is mounted on the device, causing a short circuit in the device circuit and causing malfunction. There is a possibility that this may occur. Furthermore, leaving the sharp edges 400' in place poses a safety problem.

In order to prevent these problems, after cutting the extra length of the lead 300 with the cutter 500, it is necessary to perform a deburring process for the lead burrs 400, 400' as shown in FIG. 7F.

(C) Prior Art Conventionally, this type of lead deburring process is often performed manually. However, with the high density wiring of printed circuit boards, the possibility of short circuits with adjacent patterns increases, and the importance of the lead deburring process has been recognized, and various methods for automating this process have been considered. One method is to dip twice. That is, after the lead cutting step, a step is performed in which the lead burrs that have been generated are immersed in the solder bath again so as to cover them from above. Another possible method is the method shown in FIG.

In the figure, the printed board 100 is held at its side edge facing a carrier (not shown) and is being transported in a nearly horizontal direction with the surface on which the lead burrs 400 are located downward. The wire brush 600 is mounted below the printed board 100 so that its shaft is pivoted horizontally and is rotationally driven so that the tip of the wire brush rubs against the lower surface of the printed board 100.

Attach multiple wire brushes 600 as necessary,
The entire lower surface of the printed board 100 is brushed to cause the lead burrs 400 to fall off from the leads 300.

(D) Problems to be Solved by the Invention However, the double dipping method not only requires a double solder depth process, but also has the possibility of shorting with adjacent patterns due to the solder depth covering burrs, etc. becomes large, and cannot cope with the increasing density of printed board patterns at all.

Furthermore, in the method of removing lead burrs using a wire brush as shown in FIG. The wire brush 600 must be replaced frequently. Also, if the wire is strong, the printed board 10
There is a problem in that the 0 pattern is scratched and damaged.

The present invention solves this problem, but when the rotating brush (nylon brush for polishing) proposed by the present invention is used instead of the conventional wire brush, the brush applied to the deburring surface of the printed board is The pressure causes the printed board to lift upwards, causing the problem that the burrs cannot be completely removed during deburring.

(, E) Means for Solving the Problems The present invention has been made to solve the above problems, and involves bringing a rotating brush into contact with a burr-generating surface such as a lead of a printed board, A device for deburring by horizontally moving the brush, which is provided with means for pressing the component mounting surface of the printed board from above, so that when the brush is brought into contact with the printed board, the brush is pressed from above. be.

(F) Example Hereinafter, an example of the present invention will be described in detail with reference to the drawings. FIG. 2 is an overall perspective view of the printed board deburring apparatus of the present invention. In the figure, 1 is a polishing nylon brush, 2 is an antistatic metal brush, 3 is a rotation motor for the polishing nylon brush, 4 is a swing motor, 5 is a movement motor, and 6
7 is a moving table; 7 is a heald for power transmission; 8 is an installation table that is swung in the X direction by a swinging motor 4; and 9 is a screw mechanism that is rotated by the belt 7 and moves the movable table in the X direction. In addition, in the figure, 21 to Z indicate the rotation direction, respectively.

Furthermore, FIG. 3(a) is a diagram for explaining the main parts of the installation position of the printed board deburring device in the printed board soldering line, and in the figure, 22 and 23 are rails on which the carrier 20 moves. . Note that the same parts in FIGS. 2, 3, and 7 are indicated by the same numbers. In addition, FIG. 3(B) shows the carrier 20 in FIG. 3(A). rail 22
．． FIG. 3 is a perspective view of the main parts with reference numeral 23 omitted.

The printed board 21 that has undergone the lead burr cutting process is transported by the carrier 20 to a position directly above the moving path of the polishing nylon brush 1 (position al in the figure), and then stopped. When stopped, the rotation motor 3 and the movement motor 5 rotate in 2..23 directions, respectively.

The rotation of the moving motor 5 is transmitted to the screw mechanism 9 by the belt 7, and by rotating this in 23 directions, the moving table 6 engaged with the screw mechanism 9 is converted into a linear motion in the X direction. As shown in FIG.
It has a movement range that moves the area directly below 1). Furthermore, as shown in FIG. 3 (b), the polishing nylon brush 1 is
The moving table 6. An installation stand 8 is installed.

Therefore, the polishing nylon brush 1 contacts the entire back surface of the printed board and removes lead burrs by its rotation. When the polishing nylon brush 1 reaches the position (C) shown in FIG. 3(A), the moving motor 5 moves in the opposite direction (
Z, direction).

Therefore, the screw mechanism also rotates in the Z direction, and the moving table 6 is returned to the position (b) shown in FIG. 3 (a). At this time as well, the polishing nylon brush 1 is rotating while contacting the back surface of the printed board 21. 1 in the X direction of this polishing nylon brush 1
The reciprocating movement completes the lead deburring process. When the polishing nylon brush 1 returns to the b1 position, the rotation motor 3 and the moving motor 5 stop, and the carrier 20 moves accordingly to transport the printed board 21 to the next cleaning process.

Here, the polishing nylon brush 1 is a nylon brush coated with an abrasive, and not only has the elasticity of the nylon but also has the polishing effect of the abrasive. Therefore, even if the printed board pattern is rotated while being pressed with a certain amount of pressure and in contact with the back surface of the pudding 11!21, the printed board pattern is not damaged, and it also has a sufficient deburring effect. Furthermore, even if the printed board 21 is curved,
The elasticity of the polishing nylon brush 1 allows it to be pressed to a certain extent, so that the polishing nylon brush 1 can be brought into contact over the entire surface of the printed board 21 and lead burrs can be removed evenly.

As described above, the carrier 20 is attached to the polishing nylon brush l.
Lead burrs can be removed by stopping the printed board on its moving path and polishing the entire back surface of the printed board while rotating the polishing nylon brush l.

Furthermore, by moving the polishing nylon brush in the The polishing nylon brush 1 can be fixed in position and can be retracted from the printed board conveyance path.Therefore, the back surface of the printed board will not be polished unnecessarily.

Next, the swinging mechanism of the polishing nylon brush 1 will be explained. A sufficient lead deburring effect can also be obtained with the embodiments described above.

However, the rotating direction of the polishing nylon brush 1 is Z.
, the lead burr removal effect is limited because it is only in the , direction, and it is difficult to remove fine lead burrs. For this reason,
The entire polishing nylon brush l is swung in the y direction by a swiveling motor 4. This swinging mechanism is shown in FIG. 1 in the diagram
0 is a cam mechanism connected to the swing motor 4, 11 is a projection provided on the cam mechanism, 12 is a sling L provided on the installation plate 8 on which the rotation motor 3 is installed, and 13 is a swing of the installation plate 8. This is the axis that guides the movement. Note that the same reference numerals as in FIG. 1 indicate the same parts, and the projection 11 is inserted into the slit 12.
By rotating the swing motor 4, the installation plate 8 is moved to the shaft 13.
It swings in the y direction along the y direction. Therefore, the polishing nylon brush 1 also swings in the y direction. Next, the effect of swinging the polishing nylon brush 1 in the y direction will be explained using Fig. 5. Figs. Yes, 300 and 400 in the figure are Figure 8,
Like FIG. 9, the lead 5 and lead burrs are shown. first(
By rotating the polishing nylon brush 1 in the 21 direction as shown in (a), the lead burr 400 attempts to separate from the lead 300 as shown in (b).

As mentioned above, since the polishing nylon brush 1 reciprocates over the entire back surface of the printed board, normal lead burrs
It can be removed by rotating in the Z/ direction.

However, fine lead burrs and the like may still be stuck to the lead 300 as shown in (b).

Therefore, by swinging the polishing nylon brush 1 in the y direction, the lead burr 400 receives pressure in two directions (
It is completely separated from the lead 300 as shown in c). In this way, by applying pressure to the lead burr 400 from two directions, the lead burr can be removed more reliably.

That is, by swinging the polishing nylon brush 1 in the y direction, pressure can be applied to the lead burr from two directions.

Next, a method for removing the charge on the brush will be explained using FIGS. 2 and 6. In FIG. 6, the same reference numerals as in FIG. 2 represent the same parts.

In all of the examples described above, a nylon polishing brush is used, and when it comes into contact with the back surface of a printed board, it becomes charged with static electricity. Therefore, if the component mounted on the printed board is a component that can be destroyed by static electricity, such as 0MO3-IC13, there is a problem. For this reason, in this example, as shown in FIG. 2, a grounding metal brush 2 for grounding the static electricity of the polishing nylon brush 1 is provided on the installation plate 8. This metal brush 2 is rotatably provided on the installation plate 8 and is further provided so as to mesh with the polishing nylon brush 1. Therefore, as the polishing nylon brush 1 rotates, the metal brush 2 also rotates. The metal brush 2 is grounded to release static electricity from the polishing nylon brush l to the ground. Also, metal brush 2
This rotation also prevents the polishing nylon brush 1 from clogging.

FIG.
This will be explained using examples of (a) and (b). In the present invention, the polishing nylon brush l rotates in the Z direction while contacting the back surface of the printed board 21. Therefore, Figure 1 (a), (
As shown in b), pressure is applied to the printed board 21 in the P direction, causing the printed board 21 to vibrate. Furthermore, the printed board 21 is often not flat but curved.

Therefore, the contact area of the polishing nylon brush 1 with the back surface of the printed board becomes small, and there is a possibility that the lead deburring effect will be reduced. Furthermore, when the polishing nylon brush 1 is oscillated, the contact area becomes even smaller.

Therefore, in this embodiment, the pressing mechanisms 24 and 25 are used to prevent the printed board from lifting up.
By pressing 1 in the Q direction, the vrwI nylon brush 1 is brought into uniform contact with the back surface of the printed board. In the embodiment shown in FIG. 1(a), the printed board 21 is partially pressed by the pressing rod 24. in this case,
The pressing mechanism 24 needs to be placed avoiding the component mounting area, and requires removal work.

In order to improve this point, in the embodiment shown in FIG. 1(b), the printed board 21 is pressed in the Q direction by a flexible weight 25. In this case, since pressure is uniformly applied to the printed board 21, no distortion occurs, and the contact area of the polishing nylon brush 1 with the back surface of the printed board can be maintained uniformly.

For example, as shown in FIG. 3(a), the carrier 20
When it reaches the position (al) and stops, the cylinder mechanism 26 lowers the flexible weight, and then
Leading by the polishing nylon brush 1 is started. After that, when the polishing nylon brush 1 returns to the position (bl), the cylinder mechanism 26 is driven again and the flexible weight 25 is lifted upward. By taking these steps,
Attachment and removal of the pressing mechanism can be automated.

Incidentally, as the flexible weight 25, for example, a sandbag or the like can be considered. Further, instead of the cylinder mechanism 26, a rotation mechanism such as a motor can be used.

(C,) Effects of the Invention As explained above, according to the present invention, the printed board is not simply passed over the rotating brush, but the rotating brush itself is moved and actively spread over the entire surface of the printed board. Lead burrs can be removed reliably.

In order to correct the vibration and curvature of the printed board, the printed board is pressed against the polishing nylon brush from the upper printed board, so that the polishing nylon brush uniformly contacts the printed board and efficiently. Can perform lead deburring.

[Brief explanation of the drawing]

FIG. 1 is a diagram showing a pressing mechanism for a printed board, and FIG. 2 is a perspective view of a lead deburring device for a printed board. Figure 3 is a diagram for explaining the positional relationship between the printed board deburring device and the printed board soldering light. Figure 4 is a diagram showing the swinging mechanism of the polishing nylon brush, and Figure 5 is a diagram showing the swinging mechanism. Figure 6 is a diagram to explain the effect of the mechanism, Figure 6 is a diagram showing the antistatic mechanism of the polishing nylon brush, Figure 7 is a diagram to explain the soldering process of a printed board, Figure 8 is the lead burr cutting process. FIG. 9 is a diagram for explaining an example of a conventional method for removing glue and burrs. 1; Nylon Brasilia for rllF111. 21; Printed board, 22, 23i rail, 24th! Fertilization (/l) 1st fl (mouth 2 4θθ /t, 4θθ (c) 2N5 diagram $40

Claims (1)

[Scope of Claims] 1) In a deburring device that removes burrs by bringing a rotating brush into contact with a burr-generating surface such as a lead of a printed board and moving the rotating brush horizontally, the component mounting surface of the printed board 1. A method for fixing a printed board in a deburring device, comprising: means for pressing from above, the printed board being pressed and fixed from above when the rotating brush is brought into contact with the printed board. 2) A patent claim characterized in that a flexible weight is used as means for pressing the component mounting surface of the printed board from above, and deforms in accordance with the shape of the component of the printed board to press the printed board. A method for fixing a printed board in a deburring device according to item 1.