JPH0446670A - Automatic soldering device - Google Patents

Abstract

PURPOSE:To manufacture a printed-wiring board excellent in reliability by constituting a conveyor for conveying the printed-wiring board of conveyors of first and second zones, providing a buffer conveyor on the front stage of the conveyor of the first zone and adjusting the speeds of these conveyors arbitrarily independently. CONSTITUTION:The conveyor for conveying the printed-wiring board 1 is constituted of the conveyor 13 of the first zone and the conveyor 14 of the second zone. The conveyor 13 of the first zone conveys the printed-wiring board 1 in a flux applying stage and a preheating stage. The conveyor 14 of the second zone conveys the printed-wiring board 1 in a soldering shape. The buffer conveyor 12 is provided on the front stage of the conveyor 13 of the first zone. The speeds of these conveyors 12, 13 and 14 can be adjusted arbitrarily independently. Consequently, soldering having satisfactory soldering quality can be performed.

Description

DETAILED DESCRIPTION OF THE INVENTION Field of the Invention The present invention relates to an automatic soldering device used for soldering electronic components to printed wiring boards.

Conventional technology In recent years, automatic soldering equipment has become more and more popular as electronic equipment becomes lighter and smaller, and semiconductor components become more highly integrated. is required to have gender.

Hereinafter, a conventional automatic soldering device will be described with reference to the drawings.

Figure 2 is a schematic diagram showing the structure of a conventional automatic soldering device. In the figure, 1 is a printed wiring board, 2 is an electronic component, 3 is a conveyor for conveying the printed wiring board 1, and 4 is a flux coating. equipment (hereinafter abbreviated as fluxer),
5 is a preheating heater; 6 is a soldering tank; as a motor 7- rotates, a primary jet stream is spouted up from the first nozzle 8 and a secondary jet stream is spouted up from the second nozzle 9, and soldered to the bottom surface of the printed wiring board 1. I do. Further, 10 is a cooling fan, and 11 is a main body of the apparatus.

The operation will be explained below.

The printed wiring board 1 on which the electronic component 2 is mounted is moved by the conveyor 3 at a constant speed in the direction of the arrow. first,
Flux (not shown) is applied to the lower surface of the printed wiring board 1 using a fluxer 4 . Next, the flux applied to the lower surface of the printed wiring board 1 is dried using a preheating heater 5, and solvents such as alcohol in the flux components are removed. At the same time, the entire printed wiring board 1 is maintained at a constant temperature. The printed wiring board 1 continues to move, and soldering is performed in the solder bath 6 by the primary jet solder spouted up in an irregular manner and the secondary jet solder gently spouted.

Finally, the entire printed wiring board 1 is cooled down by the cooling fan 10 and is carried out from the main body 11 of the apparatus.

Problems to be Solved by the Invention However, in the conventional automatic soldering apparatus described above, it is difficult to set and control conditions such as the amount of flux applied, the preheating time, or the contact time between the jet solder and the printed wiring board.
This is uniformly determined by the speed of the conveyor 3.

For example, if it is desired to lengthen the preheating time for a printed wiring board 1 or the like having a large heat capacity, the speed of the conveyor 3 may be reduced. However, if the speed of conveyor 3 becomes slower,
The immersion time in the solder bath 6 is long (as a result, the thermal stress on the printed wiring board 1 is large and there is a risk of component destruction. Also, due to problems with the heat resistance of the electronic components 2, etc., the solder bath 6
If the immersion time has to be shortened, the speed of the conveyor 3 needs to be increased. However, if this is done, the preheating time is shortened, the flux cannot be dried sufficiently, and flux gas is sometimes generated during soldering, making it difficult to apply solder sufficiently. As described above, the conventional automatic soldering apparatus has a problem in that when performing soldering, the automatic soldering apparatus does not have a high degree of freedom in setting conditions and controlling methods using the apparatus.

The present invention solves the above problems, and aims to provide an excellent automatic soldering device in which the preheating time and the immersion time in a solder bath can be freely set.

Means for Solving the Problems In order to achieve the above object, the present invention provides a conveyor for conveying printed wiring boards in a flux application process and a preheating process (hereinafter referred to as the first zone), and a soldering process (hereinafter referred to as the first zone). A buffer conveyor is installed before the first zone, and the conveyor speed of the first zone can be arbitrarily adjusted to adjust the amount of flux applied and the preheating time under appropriate conditions. The conveyor speed in the second zone can also be adjusted arbitrarily.

Therefore, according to the present invention, by dividing the conveyor for conveying printed wiring boards into two and further providing a buffer conveyor, the speed of each conveyor can be independently and freely controlled, and the flux to the printed wiring boards can be controlled. By freely setting and controlling the coating amount and preheating time, or the contact time between the jet solder and the printed wiring board in the solder bath, you can apply the appropriate solder to a wide variety of printed wiring boards. It becomes possible to apply soldering, and the quality of soldering can be improved.

Embodiment Hereinafter, regarding an embodiment of the present invention, parts that are the same as those in FIG. 1 and FIG. FIG. 1 is a front view showing the schematic structure of an automatic soldering apparatus according to an embodiment of the present invention. Reference numeral 12 denotes a buffer conveyor for conveying a printed wiring board 1. In FIG. Further, 13 is a conveyor 14 of the first zone, and a conveyor 14 of the second zone is a buffer conveyor 12 that sequentially conveys the printed wiring boards l conveyed into the apparatus together with the conveyor 13 of the first zone. .

Next, the operation of the above embodiment will be explained.

The printed wiring board 1 on which the electronic component 2 is mounted moves in the direction of the arrow and waits on the buffer conveyor 12.

. At this time, the speeds of the conveyor 13 in the first zone and the conveyor 14 in the second zone are not necessarily the same. For example, if the conveyor 13 in the first zone is slower than the conveyor 14 in the second zone, the buffer conveyor The timing for carrying in the printed wiring board 1 waiting on the conveyor 12 must be synchronized with the slow conveyor speed of the conveyor 13 in the first zone. That is, the carry-in timing must be synchronized with the slow conveyor speed of the conveyor 13 in the first zone or the conveyor 14 in the second zone. The printed wiring board 1 is transported according to such delivery timing, and an appropriate amount of flux is applied to its lower surface by the fluxer 4. At this time, if the conveyor speed of the conveyor 13 in the first zone is high, only a small amount of flux is applied. On the other hand, if it is slow, a large amount will be applied. Next, the printed wiring board 1 passes over a preheating heater 5 to completely dry the flux. At the same time, the temperature of the entire printed wiring board 1 is maintained at a constant temperature. At this time, the temperature setting of the preliminary heater 5 or the speed of the conveyor 13 in the first zone is set to an appropriate value in consideration of the heat capacity of the printed wiring board 1. Next, the printed wiring board 1 is transferred to the conveyor 14 in the second zone. Here, the irregularly spouting primary jet stream and the quietly spouting secondary jet stream from the solder bath 6 come into contact with the lower surface of the printed wiring board 1. Ideal soldering can be achieved by setting the dipping time to an appropriate condition by adjusting the speed of the conveyor 14 in the second zone. Finally, the entire printed wiring board 1 is cooled down by the cooling fan 10, and the automatic soldering device is carried out of the main body 11 of the apparatus.

According to this embodiment, by arbitrarily adjusting the speed of the conveyor 13 in the first zone, the amount of flux applied to the lower surface of the printed wiring board 1 and the preheating time can be controlled to appropriate conditions. By arbitrarily adjusting the speed of the conveyor 14 in the second zone, the immersion time of the printed wiring board 1 in the solder bath 6 can be controlled to appropriate conditions.

In addition, in this embodiment, the buffer conveyor 12, the first
The same effect can be obtained by using each or all of the zone conveyor 13 and the second zone conveyor 14 as an inclined type or as a horizontal type.

Effects of the Invention As described above, according to the automatic soldering device of the present invention, the amount of flux applied to the printed wiring board, the preheating time, or the immersion time in the solder bath can be set to appropriate conditions, and it is possible to Since extremely good soldering can be performed on a wide variety of different printed wiring boards, it is possible to perform soldering with high quality, resulting in the effect that printed wiring boards with excellent reliability can be manufactured.

[Brief Description of the Drawings] Fig. 1 is a front view showing a schematic structure of an automatic soldering device according to an embodiment of the present invention, and Fig. 2 is a front view showing a schematic structure of a conventional automatic soldering device. be. 1...Printed wiring board, 12...Buffer conveyor 13...Conveyor in the first zone 14...Conveyor 7 in the second zone
°SuJ+! , 1 piece of "J thread"

Claims (2)

[Claims] (1) The printed wiring board conveyor is divided into a first zone conveyor that conveys the printed wiring board in the flux application process and preheating process, and a second zone conveyor that conveys the printed wiring board in the soldering process. An automatic soldering device comprising: further comprising a buffer conveyor upstream of the conveyor in the first zone, and the speeds of these conveyors can be arbitrarily adjusted independently. (2) The automatic soldering apparatus according to claim 1, wherein at least one of the three conveyors is used as an inclined conveyor or a horizontal conveyor.