JPS6233023B2 - - Google Patents

Description

[Detailed Description of the Invention] This invention provides a method for soldering while melting solder using a soldering iron, and in particular, prevents solder from adhering to the soldering iron that has been pulled up at the end of soldering work, and prevents solder from adhering to the soldering iron. In addition to ensuring the amount of adhesion to the top,
The present invention relates to a soldering method that can stabilize the shape of solder deposits.

FIG. 1 is a perspective view showing, as an example, a state in which a joint consisting of a covered wire end and a terminal plate is to be soldered by a conventional soldering method. In the figure, 1 is a soldering iron, 2 is solder to be melted, and 3 is a soldering iron.
Reference numeral 4 indicates a covered wire end, and 4 indicates a terminal plate to be joined to this covered wire end.

In the above method, the soldering iron 1 is brought into contact with the joint consisting of the coated wire end 3 and the terminal plate 4, and the solder 2 is melted and soldered. Figure 2 a is
A state in which solder is being fed and melted to the joint shown in FIG. 1 is shown, and in the figure, 5 indicates molten solder. Next, the soldering iron 1 is pulled up and cooled down to complete the soldering work. FIG. 2b shows a state in which the soldering iron 1 is pulled up after the solder 2 is fed to the joint as shown in FIG. Shows molten solder adhered to.

As shown in Figure 2b, in the conventional soldering method, the soldering iron 1 is generally used, although there are some differences in the amount due to differences in the joint shape, tip shape, solder feed amount, etc. A large amount of solder adheres to the iron tip during pulling up, and the amount of solder adhering also varies, so the amount of solder adhering to the joint and the shape of the solder pile are not constant. Therefore, the automatic soldering method in which a fixed amount of solder 2 is fed has the disadvantage that it may cause too much solder or not enough solder.

This invention was made in order to eliminate the drawbacks of the conventional ones as described above, and when pulling up the soldering iron 1, the temperature of the molten solder 5 near the iron tip is prioritized compared to other molten solder parts. raised to;
A soldering method that prevents solder from adhering to the soldering iron 1 by lowering the viscosity and surface tension compared to other parts, and makes it possible to keep the amount of solder adhering to the joint and the shape of the solder constant. is intended to provide.

FIG. 3 is a front view showing the state of a basic experiment for confirming the principle of this invention. FIG. 3a shows a state in which molten solder 7 is filled between two copper round bars 6a and 6b of the same shape that have flat end faces and are heated above the melting point of the solder. The rod 6a is heated to a higher temperature than the other round copper rods 6b. Fig. 3b shows a state in which the copper round bars 6a and 6b are pulled from the state shown in Fig. 3a, and the molten solder 7 is separated, 7a is the molten solder adhering to the copper round bar on the high temperature side, and 7b is the molten solder on the low temperature side. Molten solder attached to the copper round bar 6b is shown. A temperature gradient is generated in the molten solder 7 based on the temperature difference given to the copper round bars 6a and 6b. The higher the temperature, the lower the viscosity and surface tension, so the amount of molten solder 7a adhering to the copper rod 6a on the high temperature side is overwhelmingly less than the amount of molten solder 7b adhering to the copper rod 6b on the low temperature side. , variations in the amount of adhesion will no longer occur.

FIGS. 4a to 4c are perspective views showing other embodiments of the present invention, and in the figures, the same reference numerals as in FIGS. 1 to 2 indicate the same or corresponding parts. 8 is a dedicated power supply, 9 is a sweetener, 10 is an electrode, and 11 is a protrusion at the tip of the soldering iron 1, which increases the temperature of the molten solder 5 during the process of pulling up the soldering iron 1 at the end of soldering. The device is configured to do this. In FIG. 4a, the soldering iron 1 and the electrode 10 face each other with a gap maintained, and with the molten solder 5 filling the gap, turning on the switch 9 connects the dedicated power supply 8, the switch 9, the electrode 10, and the molten solder. 5. A circuit is formed between the soldering irons 1. Similarly, in FIG. 4b, the electrodes 10 face each other at a distance from each other near the tip of the soldering iron 1, and with the molten solder 5 spaced apart, turning on the switch 9 turns on the dedicated power source. 8, a circuit is formed between the switch 9, the electrode 10, the molten solder 5, and the electrode 10. In FIG. 4c, the protrusion 11 is provided on the soldering iron 1, so when the switch 9 is turned on, a circuit is formed between the dedicated power supply 8, the switch 9, the protrusion 11, the soldering iron 1, and the protrusion 11. It's getting old.

In FIG. 4a, when soldering using the soldering iron 1, in the process of pulling up the soldering iron 1 at the end of the soldering work, a special power source 8 is connected between the soldering iron 1 and the molten solder 5. The temperature of the molten solder 5 near the tip of the soldering iron 1 is preferentially increased by the resistance heat generated by passing an electric current through the soldering iron 1, and the viscosity and surface tension of the molten solder 5 are reduced. It is possible to prevent solder from adhering to the soldering iron tip, and to keep the amount of solder adhering to the joint and the solder shape constant. In FIG. 4b, in the process of pulling up the soldering iron 1 in the same manner as above, a second This produces the same effect as the case in Figure 4a. In FIG. 4c, in the same way, in the process of pulling up the soldering iron 1, from the dedicated power source 8 through the protrusion 11,
The resistance heat generated by passing a current through the tip of the soldering iron 1 produces the same effect as in the case of FIG. 4a. FIG. 5 is a perspective view showing the soldering result when soldering is performed using the method described above, and the electrode 10 and the like are omitted.
This shows that no molten solder 5b is attached to the soldering iron 1 after soldering.

In the above embodiment, one pair of electrodes has been described, but a plurality of pairs of electrodes may be provided. Furthermore, the means for passing the current is not limited to that of the above embodiment, but other structures and shapes can be used.

As described above, according to the present invention, in the process of pulling up the soldering iron 1, the temperature of the molten solder 5 near the tip is raised preferentially, and the viscosity and surface tension of that part are lowered. This has the effect of preventing solder from adhering to the soldering iron and keeping the amount of solder adhering to the joint and the shape of the solder constant.

[Brief explanation of the drawing]

Fig. 1 is a perspective view showing the state immediately before soldering in the conventional soldering method, Fig. 2 a is a perspective view showing the state in which the soldering is being performed, and Fig. 2 b is the state immediately after soldering. FIG. 3 is a perspective view showing the basic experiment of this invention; FIGS. 4 a to c are perspective views showing other embodiments of the invention, and FIG. 5 is a perspective view showing the soldering results. It is a diagram. In the drawings, the same symbols indicate the same or equivalent parts, 1 is the soldering iron, 2 is the solder, 3 is the coated wire end, 4 is the terminal board, 5, 5a, 5b is the molten solder, 6a, 6b is the copper A round bar, 7, 7a, and 7b are molten solder, 8 is a dedicated power source, 9 is a switch, 10 is an electrode, and 11 is a protrusion.

Claims (1)

[Claims] 1. In a method of soldering while melting solder using a soldering iron, current is applied to the molten solder at or near the tip of the soldering iron during the process of pulling up the soldering iron at the end of the soldering work. A soldering method characterized by a soldering method.