JPH0435005Y2 - - Google Patents

Description

[Detailed Description of the Invention] [Industrial Application Field] The present invention relates to a soldering bath used in automatic soldering equipment and the like.

[Conventional technology]

In the soldering bath of automatic soldering equipment, the solder is melted by a heater. There are two methods for installing a heater in a soldering bath: an ``immersion heater,'' in which a sheathed heater is inserted into the soldering bath through a hole protruding from the wall of the soldering bath, and an ``external heater,'' in which the heater is attached to the outside of the soldering bath in contact with the soldering bath. attached heater”
There is.

[Problem that the invention attempts to solve]

Immersion heaters have very high thermal efficiency because the heater comes into direct contact with the molten solder, but since the sheath heater is installed directly into the hole by drilling a hole in the wall of the solder bath, there is a gap between the hole and the heater. There is a risk of molten solder leaking from the Therefore,
In immersion heaters, mechanical means have been used, such as sealing the sheath (outer cylinder) and the hole by welding, or filling the space with a sealing material and tightening with screws.

Therefore, with immersion heaters, when the heater is broken or the heater is replaced to change the capacity, if the heater is attached by welding, the attached part is melted with a flame such as oxygen-acetylene flame and the sheath is replaced. The heater must be removed,
A great deal of time and effort was required for the preparation of the flame device and the fusing work. In addition, in cases where the sheath heater is attached by mechanical means, solder often sticks to the threaded portion or the fitting portion, or seizes due to the heat, making it difficult to remove the sheath heater.

Furthermore, with the immersion heater, the sheath part sometimes breaks off from the heater attachment part after long-term use. This is because the long heater, which is fixed at only one end, is moved greatly by the thermal expansion and contraction of the solder. That is, when the electricity to the heater is turned off at the end of the soldering operation, the solder that has been melted in the solder bath cools and solidifies. At this time, the solder contracts and bends the heater in the direction of the solder's contraction. When the soldering operation is restarted, the solidified solder is melted by a heater, but since the solder expands thermally, the heater is bent in the direction of thermal expansion, which is opposite to the direction of contraction. In this way, as the solder in the solder bath is repeatedly solidified and melted, the mounting portion suffers metal fatigue and breaks.

By the way, in a soldering bath, before starting the soldering work, it is necessary to melt the solidified solder in the soldering bath. The solder melts first, and the melted solder thermally expands and becomes solid at the top.
It can spray out forcefully upward from the gap, which is extremely dangerous. This can be prevented by melting the top solder first or by melting all the solder at the same time. For this purpose, it is known that a heater should be installed at the top of the soldering bath, but in the case of a sheath heater used as an immersion heater, the sheath that covers the heater is close to the heater, and the sheath is very close to the heater. Because of the high temperatures, if a sheath heater was installed at the top of the solder bath, there was a risk that the oxidation-preventing cover wax floating on the solder liquid surface would catch fire.

On the other hand, external heaters are easy to replace, and because they are indirect heating that heats through the wall of the soldering bath, they do not generate high temperatures locally, and do not require cover wax even when installed above the soldering bath. There's no such thing as setting it on fire. However, external heaters have the disadvantage of extremely low thermal efficiency and higher power consumption than immersion heaters. In particular, when the heater is cylindrical, the contact with the solder wall surface becomes a line contact, which further deteriorates thermal efficiency.

The purpose of the present invention is to provide a soldering bath in which the heater is easy to replace, the heater does not break even after long-term use, and even when installed on the top of the soldering bath, it does not burn the cover wax and has good thermal efficiency. There is a particular thing.

[Means for solving problems]

According to the present invention, the above object is achieved by installing a pipe in a solder bath, making it easy to take the heater in and out of the pipe, and holding both ends of the pipe.

The feature of this invention is that a pipe with a closed tip is sealed and fixed to one wall of the solder bath with the opening of the pipe exposed to the outside, and a pipe fixed to the other wall of the solder bath is sealed. A soldering bath characterized in that the tip of the pipe is slidably held in the holding part, and a heater is inserted through the opening of the pipe.

[Effect]

Since one end of the pipe is fixed and the other end is slidably held, it is difficult to bend due to thermal expansion and contraction of the solder and the pipe.

One end of the pipe is opened to the outside of the wall surface, and the heater can be taken in and out through the opening, making it easy to replace the heater.

The fact that the heater heats the solder through the pipe reduces thermal efficiency somewhat, but since it does not cause a fire even if it touches the cover wax, the heater can be installed on top of the solder bath, and when the solder melts, it prevents solder from flowing inside. Prevents blow-up.

〔Example〕

A pipe 4 whose tip is closed is installed between opposing wall surfaces 2 and 3 of the solder bath 1. The pipe is attached by having an opening 5 of the pipe exposed to the outside on one wall surface 2, and fixing the wall surface 2 and the pipe 4 with a weld bead 6, and sealing the space between them. Further, on the other wall surface 3, the tip of the pipe is slidably inserted into a pipe-shaped holding portion 7 fixed to the wall surface 3 by welding or the like. In such an installation in which one end is slidably held, even if the pipe itself expands and contracts thermally due to heating and cooling of the solder, this is absorbed by the holding portion, so that the pipe will not be deformed. Further, a hole 8 is bored in the pipe-shaped holding part 7. The hole is for letting out the air that has been in the holding part, and allowing the molten solder that has entered the holding part to come in and out when it thermally expands and contracts.

A heater 9 is connected to the opening 5 extending outside the solder bath.
is inserted into the pipe 4 and attached to the wall of the solder bath in an appropriate manner.

〔effect〕

According to the present invention, it is extremely easy to replace the heater, and because one end of the pipe is slidably inserted into a pipe-shaped holding part fixed to the wall of the solder tank, thermal expansion and contraction of the solder This prevents deformation of the pipe, and since heating through the pipe does not burn up the cover wax, it is possible to install a heater on the top of the solder bath, thereby suppressing solder spouting when melting the solder.

[Brief explanation of drawings]

FIG. 1 is a perspective view of the solder bath of the present invention, and FIG. 2 is a front sectional view thereof. 1...Solder bath, 2, 3...Wall surface, 4...Pipe, 5...Opening, 9...Heater.

Claims (1)

[Scope of utility model registration request] The pipe with the tip closed is sealed and fixed to one wall of the solder bath with the opening of the pipe exposed to the outside, and the tip of the pipe is fixed to the other wall of the solder bath using a pipe-shaped holding part fixed to the other wall of the solder bath. A soldering bath characterized by being slidably held and having a heater inserted through an opening in the pipe.