JPH0322599A - Electronic component mounting equipment - Google Patents

Abstract

PURPOSE:To enable an electronic component to be mounted on a printed board with an optimal pressure and to prevent the occurrence of a solder bridge by a method wherein a holding body is made to hold by suction a printed board warped upward, and then the holding body is made to descend to correct the warpage of the printed board. CONSTITUTION:If a printed board is warped by a warpage volume of epsilon, a holding body 9 for holding a printed board by vacuum clamping is made to ascend from a recess 8A of a support 8 and to come into contact with a printed board 6. Then, when the holding body 9 is made to such the printed board 6 by a suction device, the body 9 is made to descend through the intermediary of a rod 12A and a bracket 13 by the motion of a cylinder 12, the body 9 is made to descend by control as holding the printed board 6 to correct the warpage of the printed board 6. As the printed board 6 corrected in warpage is kept distant from a component mounting device 5 by a certain distance, in this state, when the electronic component 1 is made to descend, a lead 1A is always pressed against a cream solder 7 of the printed board 6 with a constant pressure and the electronic component 1 can be mounted in a proper state.

Description

[Detailed Description of the Invention] [Industrial Application Field] The present invention relates to an electronic component mounting machine, and more specifically, to prevent adjacent solder cream from flowing and merging when soldering leads of electronic components. This article relates to an electronic component mounting machine that can.

(Prior Art) First, the overall configuration of a conventional electronic component mounting machine will be described with reference to FIG. 2. As shown in FIG. 3, a conventional electronic component mounting machine has a component supply section (2) that supplies electronic components (1).
), a component supply device (4) that sucks the electronic component (1) from the component supply section (2) and supplies it to the positioning device (3) for the electronic component (1); The electronic components (1) that have been supplied and positioned are sucked into the suction nozzle (5).
A), the suction nozzle (5A) is lowered from a predetermined height at a predetermined position of the printed circuit board (6), and the lead (IA) of the electronic component (1) is attached to the printed circuit board as shown in FIG. (6) A component mounting device (5) that lightly presses and mounts the component onto the cream solder (7) above, and the component mounting device (
5), and a support body (8) that supports the printed circuit board (6) when the electronic component (1) is mounted.

If the printed circuit board (6) has cream solder (7) in advance as shown in FIG. 5, and the printed circuit board (6) is not warped as shown by the imaginary line in FIG. By lowering the suction nozzle (5A) of (5) from a preset height, the lead (IA) of electronic component (1) can be attached with an appropriate pressing force as shown in Figure 5. .

[Problem to be solved by the invention]

However, the conventional electronic component mounting machine always lowers the suction nozzle (5A) from a preset height to mount the electronic component (1), regardless of the state of the printed circuit board (6). There is. Therefore, if the suction nozzle (5A) is lowered while the printed circuit board (6) is still warped upward as shown in Fig. 3, the electronic component (6) will be moved by the amount of warp. ), as shown in Figure 6, the lead (IA) should be deeply burrowed into the cream solder (7).
) protrude and expand around the cream solder (7). (7) may coalesce and cause a solder bridge. If the electronic component (1) is pressed too much against the printed circuit board (6), it may slip between it and the mounting nozzle (5A) and shift laterally, as shown in Figure 7. A solder bridge is formed as shown. In particular, to determine whether the electronic component (1) is properly mounted on the printed circuit board (8), it is necessary to sufficiently control the mounting pressure per lead (l8), that is, the pressing load against the cream solder (7). The slight amount of warpage of the printed circuit board (6) greatly affects the quality of mounting of the electronic component (1).
Moreover, as described above, if the printed circuit board (6) is warped upward, the support (8) cannot correct the warp, and the product is likely to be defective. Moreover, these things become more noticeable as the pitch between the leads (IA) and (IA) of the electronic component (1) becomes smaller.

The present invention has been made to solve the above problems, and is an electronic component mounting machine that mounts electronic components on a printed circuit board with an optimal pressing force without being affected by the warpage of the printed circuit board, and that does not cause solder bridges. It provides:

[Means to solve the problem]

In the electronic component mounting machine of the present invention, a suction body for adsorbing the printed circuit board is movably provided on a support body that supports the printed circuit board from the bottom surface, and the suction body is attached to the upwardly warped printed circuit board. It is configured to control the lowering of the printed circuit board to a position where the warp is corrected.

(Function) The electronic component mounting machine of the present invention attaches the suction body to the upwardly warped printed circuit board, and then lowers the suction body to correct the warpage of the printed circuit board and connect the component mounting device and the printed circuit board. Keep a predetermined distance constant.

〔Example〕

Hereinafter, based on the embodiment shown in FIGS. 1(a) and 1(b), parts that are the same as or equivalent to those of the prior art will be given the same reference numerals, and the description thereof will be omitted, and the description will focus on the features of the present invention. FIGS. 1(a) and 1(b) are cross-sectional views showing the main parts of an embodiment of the electronic component mounting machine of the present invention, and FIG. A diagram showing a state in which the printed circuit board is attracted to the back surface, and a diagram (b) in FIG.

The electronic component mounting machine of this embodiment is shown in Figs. 1(a) and (b).
), a support body (8) that supports the printed circuit board (6) from the back surface is provided, and an adsorption body (9) that attracts the printed circuit board (6) from the back surface to the support body (8) is movable up and down. The rest of the structure is the same as the conventional one.

The adsorbent (9) will be described in detail.
) is raised and lowered from a recess (88) formed in the axial direction of the support (8) formed in a cylindrical shape, as shown in FIGS. 1(a) and (b). It is configured to be able to appear and disappear from (8A). A long hole (9^) that matches the glaze core is formed through the adsorbent (9), and the long hole (9A)
The elongated hole (9A) is reduced in pressure by a suction device (not shown) via an air hose (10) connected to the air hose (10), and the printed circuit board (6) is adsorbed by the adsorbent (9).

The adsorbent (9) also includes a main body (9B), a rod part (9C) connected downward from the main body (9B), and a flange part (9D) formed at the lower end of the rod part (9C). )
The rod portion (9C) has a body portion (9B) that surrounds the rod portion (9G) and is integrally formed with the rod portion (9C).
A spring (11) is elastically mounted between the lower surface of the support body (8) and the bottom surface of the recess (8A) of the support body (8), so as to constantly bias the suction body (9) upward. A cylinder (12) is disposed below the adsorbent (9), and the rod (12A) of the cylinder (12) is connected to the flange portion of the adsorbent (9) via a bracket (13). (9
D), the cylinder (12) is connected to the rod (12
By operating A), the adsorbent (9) can be moved in and out of the recess (8A) of the support (8).

In addition, (l4) is the rod (12A) of the cylinder (12).
) is a nut that connects the bracket (13).

According to this embodiment, when the printed circuit board (6) is warped upward by the amount of warpage (ε), the urging force of the spring (ll) moves the adsorbent (9) into the recess (8A) of the support (8). )
(see Fig. 1(a)), and then the suction device lifts the printed circuit board (6) up to contact with the printed circuit board (6).
), the cylinder (12) is actuated to lower the suction body (9) through its rod (12A) and bracket (13), and the suction body (9) attaches to the printed circuit board (6).
) is sucked and controlled to descend to the support surface of the support body (8) to correct the warpage of the printed circuit board (6) (Fig. 1 (b)
reference). Since there is a certain distance between the printed circuit board (6) whose warp has been corrected and the component mounting device (5) described above, in this state, the electronic component (6) is mounted as shown in FIG. 1(b). When the lead (1) is lowered, the lead (1) is always lowered with a constant pressing force.
A) is pressed onto the cream solder (7) of the printed circuit board (6), and the electronic component (1) can be mounted in the proper state as shown in FIG.

In the above embodiment, the spring (1l) and the cylinder (12) were used as an example of means for raising and lowering the adsorbent (9), but any means that can control the raising and lowering of the adsorbent (9) may be used. It is not limited to the examples. Needless to say, the arrangement of the adsorbent (9) on the support (8) is not limited to the above embodiment.

〔Effect of the invention〕

As described above, according to the present invention, it is possible to provide an electronic component mounting machine that mounts electronic components on a printed circuit board with an optimal pressing force without being affected by warpage of the printed circuit board, and does not cause solder bridging.

[Brief explanation of drawings]

Figure 1(a). (b) is a sectional view showing a main part of an embodiment of the electronic component mounting machine of the present invention, and (a) is a diagram showing a state in which the suction body is suctioned to the back side of a warped printed circuit board. (b) is a diagram showing the state in which the suction body is lowered to correct the warpage of the printed circuit board, Figure 2 is a perspective view showing the overall configuration of the electronic component mounting machine, and Figure 3 is a diagram showing the conventional electronic component mounting machine. Figure 4 is an enlarged sectional view of the printed circuit board before electronic components are mounted, and Figure 5 is an enlarged view of the printed circuit board with electronic components mounted in a normal state. A cross-sectional view, Fig. 6 is a view corresponding to Fig. 5 showing a state in which an electronic component is firmly attached to form a hunter bridge, and Fig. 7 is a state in which slipping occurs between the mounting nozzle and the electronic component to form a solder bridge. FIG. 5 is a diagram corresponding to FIG. In each figure, (1) is an electronic component, (5) is a component mounting device, (6) is a printed circuit board, (8) is a support, (9) is an adsorbent, and (ε) is an amount of warpage. In each figure, the same reference numerals indicate the same or corresponding parts.

Claims (1)

[Claims] In an electronic component mounting machine that lowers a component mounting device from a predetermined distance above a printed circuit board whose lower surface is supported by a supporting body to mount electronic components on the printed circuit board, an adsorption body that attracts the printed circuit board to the supporting body is provided. 1. An electronic component mounting machine, which is movable up and down, and is controlled to descend to a position where the suction body is sucked onto the upwardly warped printed circuit board and the warp of the printed circuit board is corrected.