JPS5829188B2 - soldering equipment - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a soldering device, and more particularly to a soldering device that creates a solder application surface by jetting molten solder, and performs automatic soldering by moving a printed circuit board on this solder application surface. The purpose of this is to stabilize the height position of the solder coated surface and to prevent waves from forming on the solder coated surface.

A conventional soldering device was constructed as shown in FIG.

That is, 1 is a solder tank, 2 is a heater for melting solder, 3 is a solder blowing drive motor, 4 is a variable speed reducer, 5 is a solder blowing pump drive shaft, 6 is a solder blowing fan,
Reference numeral 7 denotes a solder blow-up duct, and when the motor 3 is rotated, a fan 6 is driven to rotate, and solder 9 is injected into the solder tank 1 from a solder blow-in port 8 provided in the duct 7 and is melted by the heater 2. is sucked in and blown up towards the opening side of the duct 7.

The opening surface of this duct 7 is located at a higher position than the solder surface 9a in the solder tank 1, and the solder blown up at the opening surface 1 of the duct 7 flows from the opening periphery of the duct 7 to the solder surface 9a of the solder tank 1 [falling down]. go.

By continuing the operation of blowing up the solder inside the duct 7, a solder coating surface 9b was formed on the opening surface of the duct 7, and the printed circuit board into which the electronic components were inserted was moved on this solder coating surface 9b. It was configured to perform automatic soldering.

However, this type of soldering apparatus is configured such that the solder blowing force of the fan 6 immediately affects the formation state of the solder application surface 9b, and therefore the solder turbulence caused by the rotation of the fan 6 is unstable. When this turbulent flow of solder is sent through the duct 7, the flow is unevenly suppressed by the inner wall surface of the duct 7, so that many small waves are formed on the solder application surface 9b and the solder is applied. A major drawback has arisen in that the surface 9b moves up and down and its height changes every moment.

Such defects can cause solder icicles to form on the conductive foil surface of a printed circuit board, or warp of solder between adjacent conductive foils, resulting in a short circuit between the conductive foils. Therefore, there was a strong demand for its resolution.

The present invention provides a soldering device that can easily overcome these conventional drawbacks, and one embodiment of the present invention will be described below with reference to FIG. 2.

In Figure 2, 11 is a solder tank, 12 is a solder melting heater,
13 is a solder lifting motor, 14 is a variable speed reducer 15 is a solder lifting pump drive shaft, and 16 is a solder lifting fan.

Next, reference numeral 17 denotes a solder ascending duct, through which the molten solder 19 in the solder bath 1 is sucked up by the rotational thrust of the fan 16 from its lower end opening 18 and sent upward.

20 is a preliminary solder tank connected to the upper end of the duct 17, which temporarily stores the solder sent through the duct 17.

Reference numeral 21 denotes a U-shaped solder blowing duct whose one end is connected to the preliminary solder tank 20, and whose other end projects upward from the solder surface 19a in the solder tank 11.

Then, the duct 2 is opened from the opening surface 20a of the preliminary solder tank 20.
The other end opening surface 21a of the duct 21 is set low, and the opening surface 21a of the duct 21 is set horizontally.

Following the above embodiment, its operation will now be explained.

The motor 13 is rotated to rotate the fan 16, and the rotational thrust of the fan 16 moves the molten solder 19 in the solder tank 11 from the lower end opening of the solder rising duct 17, that is, the solder suction port 18, to the solder surface 19a in the solder tank 11. rise above.

This raised solder is injected into the preliminary solder tank 20, but when the opening surface 20avC1 of the preliminary solder tank 20 is filled with solder, the extra solder is placed on a part of the opening periphery of the preliminary solder tank 20. The solder surface 19a in the solder tank 11 from the diversion port 22
K gradually decreases, and the solder surface in the preliminary solder tank 20 coincides with the opening surface 20a of the preliminary solder tank 20 in this embodiment.

Next, the solder in the preliminary solder tank 20 is sent through the solder blower duct 21 to the other end opening of this duct 21, that is, the solder spout 21a, and the solder in the solder tank 11 flows from the periphery of the spout 21a. Surface 19a [decreases.

The solder jet pressure from the solder spout 21a of the duct 21 is generated by the head difference HvC between the opening surface 20a of the preliminary solder tank 20 and the opening surface 21a of the duct 21, and the amount of solder jetted out is adjusted by the preliminary solder tank 20. This can be easily done by changing the relative height position of the opening of the duct 21 and the other end of the duct 21.

That is, the head H may be changed by changing the height position of the preliminary solder bath 21 or the height position of the opening at the other end of the duct 21.

As described above, in the soldering apparatus of this embodiment, a preliminary solder tank is provided, solder is once sent there, and the solder is squirted from the duct due to the head difference between the preliminary solder tank 20 and the solder blowing duct 21, and the solder is applied to the solder application surface 19b. Therefore, the solder coating surface 19b hardly moves up and down even when the rotation of the fan 16 changes, and a stable solder coating surface close to a mirror surface can be obtained without causing small waves.

In addition, since the solder flow passing through the solder blow-up duct 21 is not a turbulent flow but a laminar flow, the diameter of the solder spout of the duct 21 and the diameter of other parts may be made the same as in the embodiment, or the diameter of the solder spout may be made the same as in the embodiment. It can also be made smaller than the diameter of other parts, and the diameter of the solder spout can be made larger than the diameter of other parts as in the conventional example, and the diameter of the other parts is limited to the size of the fan 16. It is not a structure without such freedom.

As explained above, in the present invention, a preliminary solder tank is provided, molten solder is once sent there, and the solder is sent from this preliminary solder tank to the solder spouting port of the solder blow-up duct by the pressure caused by the difference in head between the two. It is characterized by the fact that
According to the present invention, phenomena such as vertical fluctuations of the solder coated surface and small waves on the solder coated surface hardly occur, and the surface is close to a mirror surface and the height position is stable.1. It is possible to obtain a solder coated surface that is uniform and of high quality.

[Brief explanation of the drawing]

FIG. 1 is a side sectional view showing a conventional soldering device, and FIG. 2 is a side sectional view showing a soldering device according to an embodiment of the present invention. 11...Solder tank, 16...Solder lifting fan 20...Preliminary solder tank, 21...
Solder blow-up duct.

Claims (1)

[Claims] 1. A solder tank into which molten solder is injected, a solder lifting means for partially lifting the solder in the solder tank, and a preliminary solder tank into which the solder lifted by the solder lifting means is injected;
A soldering device comprising: a duct that communicates with the preliminary solder tank and has a solder jet port at one end, the solder jet port surface of the duct being lower than the opening surface of the preliminary solder tank.