JPH02194690A - Solder coating device for printed board - Google Patents

Abstract

PURPOSE:To facilitate the removal of a solder and to improve productivity by a method wherein when a printed board is dipped into a fused solder tank to perform a solder coating and the substrate is pulled up to remove the excessive solder, most of the excessive solder is first sucked and removed: subsequently, a high-temperature and high-pressure hot air is sprayed to remove the residual part. CONSTITUTION:A printed board 1 coated selectively with a solder resist is mounted and suspended to and from a vertically moving means 2 bring arranged on the outside over a fused solder tank 3 filled with a fused solder 3a and hot air spraying means 4 for spraying a hot air toward the outer periphery of the substrate 1 and sucking and removing means 6 are mounted in the upper and lower two steps in the order of these means 4 and 6 in a case body 5, in which the tank 3 is housed. After a device is constituted in such a way and a solder is adhered on the substrate 1, the substrate 1 is pulled up, most of the excessive solder is first sucked and removed by the means 6, subsequently, a hot air is sprayed on the remaining excessive solder through nozzles being provided in the means 4. In such a way, the removal of the solder is executed in a two step manner and a uniform solder film only is left.

Description

[Detailed Description of the Invention] [Object of the Invention] (Field of Industrial Application) The present invention relates to a solder coating device for printed circuit boards,
The present invention relates to a solder coating device for printed circuit boards that is improved so as to be able to efficiently remove excessively deposited solder.

(Prior Art) As is well known, in the final manufacturing process of printed circuit boards, after selectively applying solder resist to the circuit pattern forming surface, a solder layer is applied to the required areas (portions where solder resist is not applied). For example, this prevents functional deterioration due to oxidation. Therefore, this type of solder coating is generally performed using a coating apparatus as schematically shown in cross section in FIG. That is, a printed circuit board 1 on which solder resist is selectively applied (adhered).
A moving means that vertically supports the board and moves it vertically can be used, for example, with an automatic transport mechanism such as a robot, and the printed circuit board 1 lowered by the moving means 2 is immersed and selectively melted.
A molten solder tank 3 for depositing Fn a, and a molten solder tank 3 that can be attached to and detached from both sides of the printed circuit board 1 which is lifted by the moving means 2 after the molten solder tank 3 selectively deposits the molten solder Fn 3a. For example, a printed circuit board solder coating apparatus comprising an air nozzle is used for blowing hot air to remove excessively deposited solder by blowing hot air at high temperature and high pressure. In addition, in the figure, 5 is a housing.

(Problems to be Solved by the Invention) According to the solder coating apparatus for printed circuit boards, the excessively adhered solder can be blown away by the high-temperature, high-pressure hot air and the desired solder coating can be achieved. There are some inconveniences.

In other words, since excessively deposited solder is blown off with high-temperature, high-pressure hot air, the thickness of the solder film tends to vary, making it difficult to form a uniform solder film, and it also tends to re-adhere to the printed circuit board and fill through holes. Koto, blown away half II
There are problems such as the need for frequent cleaning and maintenance of the coating equipment since the air nozzle may become clogged due to I dregs and flux. Furthermore, there are reports that the blown-off solder errors and flux are scattered in the air, which tends to worsen the working environment around the device.

[Structure of the Invention] (Means for Solving the Problems) The present invention has been made in response to the above-mentioned circumstances, and uses a solder coating apparatus having the above-mentioned structure to blow off solder excessively adhered to a printed circuit board. The key point is that a means for suctioning and removing the excessively deposited solder is provided.

In other words, the main idea is to remove excess solder in two stages.

(Function) According to the coating apparatus according to the present invention, the solder excessively adhered to the printed circuit board due to immersion in the molten solder tank is pulled up from the molten solder tank, and then first removed by suction and removal means. Even after this suction removal, the excess solder still remaining on the tube is blown off with hot air and removed. In other words, the amount of solder layer that must be blown away with hot air is significantly reduced, which prevents solder scum and flux from scattering, clogging the air nozzle, and re-adhering to the printed circuit board, while also reducing the deterioration of the working environment. Prevented.

(Example) The present invention will be described in detail below with reference to FIG. ji1
The figure is a sectional view showing the main part configuration of the solder coating apparatus for printed circuit boards according to the present invention, and is configured as follows. That is, a moving means that vertically supports the printed circuit board 1 on which the solder resist is selectively applied and moves it in the vertical direction includes an automatic transport mechanism such as a robot, and the printed circuit board 1 lowered by the moving means 2. a molten solder tank in which molten solder 3a is selectively applied by immersing the printed circuit board 1 in the molten solder tank 3; A suction removal means 6 which is disposed so as to be able to come into contact with and separate from the side and which suction removes at least most of the solder having excessive troughs. Means 4 uses, for example, an air nozzle to blow hot air, which is disposed so as to be able to come into contact with and separate from both sides of the printed circuit board 1 that is lifted up by means 2, and removes the excess solder that still remains by blowing hot air at high temperature and high pressure. This is a solder coating device for printed circuit boards. The hot air blowing means 4 and the suction removal means 6, for example, are operated by an air cylinder or an oil cylinder, and when the pudding 14 plate 1 descends, they move backward and away, and when the solder is applied and rise, they move forward. It is configured to be close to each other. Furthermore, these hot air blowing methods
The suction removal means 6 has a length sufficient to cover the inside of the printed circuit board 1 to be soldered,
Further, it is adapted to move toward and away from (advance and retreat) substantially downward with respect to the printed circuit board.

In the above configuration example, the hot air blowing means 4 and the suction removing means 6 are configured to have a length sufficient to cover the inside of the printed circuit board 1 to be soldered, but depending on the area to be soldered, does not necessarily have to extend over the entire r11 direction.

[Effects of the Invention] As described above, according to the solder coating device for printed circuit boards according to the present invention, adhesion (coating) can be achieved by immersion in a molten solder bath.
Most of the excess solder 1 is first removed by suction, and then the remaining portion is removed by blowing high-temperature, high-pressure hot air. In this way, since the excess solder is removed in two steps, the excess can be easily removed while leaving the required --shaped solder film. Moreover, since the residual amount removed by blowing high-temperature, high-pressure hot air is reduced and reduced in volume by suction removal as described above, the degree of scattering is also significantly reduced. Therefore, for example, clogging of air nozzles, clogging of through holes on printed circuit boards, and re-adhesion (solder) to printed circuit boards are completely prevented.
As a result, the frequency of cleaning and maintenance of the equipment is reduced, which not only contributes to improved productivity but also improves the working environment.

[Brief explanation of the drawing]

FIG. 1 is a sectional view showing an example of the configuration of a solder coating apparatus for printed circuit boards according to the present invention, and FIG. 2 is a sectional view showing an example of the configuration of a conventional solder coating apparatus for printed circuit boards. 1... Printed circuit board 2... Moving means 3... Melting semi-11I tank 3a... Molten solder 4... Hot air blowing means 5... Housing 6... Suction removal means Applicant Stock Company Toshiba

Claims (2)

[Claims] (1) A moving means that vertically supports a printed circuit board on which solder resist has been selectively applied and moves it vertically, and a printed circuit board lowered by the moving means is immersed and selectively coated with molten solder. a molten solder bath, and a suction removal means that is detachably disposed on both sides of a printed circuit board that is covered with molten solder in the molten solder bath and that is moved up by a moving means, and that sucks and removes excessively coated solder; A solder coating apparatus for a printed circuit board, comprising: hot air blowing means for removing the excess adhered solder remaining on the suction-removed surface by blowing hot air. (2) A moving means that vertically supports a printed circuit board on which solder resist has been selectively applied and moves it vertically; and a printed circuit board lowered by the moving means is immersed and selectively coated with molten solder. a molten solder bath, and a suction remover for suctioning and removing excessively adhered solder, which is disposed substantially downwardly so as to be able to come into contact with and separate from both sides of the printed circuit board, which is covered with molten solder in the molten solder bath and is lifted up by a moving means. A solder coating device for a printed circuit board, comprising: a means for blowing hot air to remove excess adhered solder remaining on the suction-removed surface by blowing hot air.