JPS6121176Y2 - - Google Patents

Description

[Detailed Description of the Invention] The present invention relates to the structure of an oxide film removal device for a molten solder bath for soldering terminals of electronic components.

2. Description of the Related Art In order to improve soldering performance when connecting lead wires of electronic components such as fixed resistors and fixed capacitors are soldered to other components, the lead wires are soldered in advance.

The lead wires are plated by immersing them in an open-top solder bath containing molten solder metal, and then pulling them out. By the way, both lead and tin, which are the main elements of solder metal, easily combine with oxygen in the air, and the upper surface of the molten solder metal is likely to be covered with an oxide film, so the oxide film is removed before dipping the lead wire. Therefore, a scraping port for the oxide film is provided on one side of the solder tank, and a scraping plate with its lower end slightly dipped in the upper surface of the molten solder metal is run from the other side of the tank toward the scraping port. , the oxide film is scraped out and swept away.

In this case, when the scraping plate advances toward the scraping port, the lower end of the scraping plate is submerged slightly below the upper surface of the molten solder metal, so the front surface of the scraping plate has an oxide film and an unoxidized molten metal. The solder metal will also be scraped up, and if the front of the scraping plate is in close contact with the edge of the scraping opening of the solder tank,
There was a problem in that the molten solder metal was also scraped out along with the scum of the oxide film at the scraping opening, and the solder metal was wasted.

As a prior art to solve this problem, for example, Japanese Patent Publication No. 57-33093 discloses that the solder tank has an inclined surface that rises along the advancing direction of the scraping plate with an appropriate gap from the inner wall of the scraping port. A guide plate is provided, and the lower end of the scraping plate is provided with a bent edge so as to contact the sloped surface of the guide plate, so that while the lower edge of the scraping plate rests on the sloped surface of the guide plate, The slag and molten metal are scraped up together, but when it comes to the gap between the guide plate and the inner wall, the molten metal falls into the tank through that gap (some of the slag also falls), and only the slag is scraped out of the tank. A device for doing so has been disclosed.

According to this, the guide plate must be placed with an appropriate gap from the inner wall of the tank, which complicates the device and shortens the effective length of the solder tank by the dimensions of the guide plate and the gap. This had the disadvantage that the device would be longer and larger.

Furthermore, if slag accumulates in the gap between the guide plate and the inner wall of the solder tank and tightly fills the gap, the molten solder metal scraped up by the scraping plate will accumulate on the slag above the gap. This prevents the slag from falling into the tank, and the scraping board scrapes it out of the tank together with the slag. Therefore, in order to eliminate this inconvenience, it is necessary to separately remove the slag within the gap at appropriate time intervals.

Therefore, in the present invention, a contact body is provided at an appropriate location on the scraping plate, and even when the scraping plate approaches the upper edge of the scraping port of the solder bath and this part and the contact body are in contact, A gap is created between the upper edge of the scraping port and the front surface of the scraper at other locations, so that the molten solder metal can pass downward through this gap and only the oxide film can be scraped out of the tank. Even with a simple configuration, waste of solder metal is eliminated.

Next, the present invention will be described based on an embodiment. In the figure, reference numeral 1 denotes a solder tank with an open top surface that stores solder metal 2 in a molten state by keeping it warm, and the front plate 3 of the solder tank 1
The upper end is bent outward and downward at a lower position than the other three side plates to form a scraping opening 4 with a slide 5.

Reference numeral 6 denotes a metal scraping plate made of stainless steel or the like having a width that is approximately the same as the width of the scraping opening 4;
is configured to be able to freely reciprocate so as to scrape up the oxide film of the molten solder metal with its front surface and discharge it to the outside of the tank 1 when it advances toward the scraping port 4. That is, a support rod 9 is attached substantially horizontally to a suitable drive means 8 such as an endless chain that is wound around the outside of the side plate 7 of the solder tank 1 and whose lower side advances in the direction of the scraping port 4, and 9 is disposed above the solder bath 1 so that its axis is perpendicular to the direction of movement of the support rod, and the scraping plate 6 is rotatably pivoted to the support rod 9 at its left and right upper ends; In the solder bath 1, the scraping plate 6 is lowered at a position farthest from the scraping port 4, and moves forward toward the scraping port 4 with its lower end immersed in the upper surface of the molten solder metal 2 to a suitable depth. death,
The scraping plate 6 is raised at an outer position beyond the scraping port 4, returns to the position farthest from the scraping port 4 in that state, and repeats the above operation thereafter.

Then, at an appropriate location such as the root portion of the scraping plate 6 near the driving means 8 or the tip on the opposite side thereof, a front surface 1 of the scraping plate 6 is placed near the lower end thereof.
4, a contact body 10 formed to protrude forward by an appropriate dimension is detachably provided with bolts 11, etc., and the front surface of the scraping plate 6 is connected to the upper edge 12 of the scraping port 4.
While the front end surface of the abutment body 10 is in contact with the upper edge 12 when approaching the abutment body 10, the abutment body 10 is placed between the front surface of the scraping plate 6 and the upper edge 12 of the scraping port 4.
A gap corresponding to the protruding dimension of is maintained over a length approximately equal to the length of the scraping plate 10, and the lower end of the scraping plate 6 is located at the rear opposite to the direction of movement of the scraping plate 6. It is configured so that it can escape and rotate upward.

Note that 13 is a slag storage box disposed below the slide 5 at the scraping port 4 of the solder tank 1.

With this configuration, the scraping plate 6 is lowered into the solder bath 1 at the farthest position from the scraping port 4, and the lower end thereof is immersed in the upper surface of the molten solder metal 2 to an appropriate length in the direction of the scraping port 4 (in the direction of the scraping port 4). When the scraping board 6 is moved forward in the direction of the arrow in Figure 1), a buoyant force is applied to the lower end of the scraping board 6, and the lower end, which is the free end, moves forward in an inclined state lagging behind in the direction opposite to the forward direction of the scraping board 6. (See solid line in Figure 3). Along with this, the front surface 1 of the scraping plate 6
In step 4, the oxide film 15 is scraped and captured. At this time, the upper surface of the molten solder metal on the front surface 14 of the scraping plate 6 is in a slightly raised state.

Next, when the scraping plate 6 approaches the upper edge 12 of the side plate 3 at the scraping opening 4, the front end surface of the front surface contacting member 10 comes into contact with the upper edge 12, and therefore, the scraping is performed at a location other than the contact point. The front surface of the panel 6 and the upper edge 1
2, a gap having a size approximately corresponding to the amount of protrusion of the abutting body 10 is created. When the upper part of the scraping plate 6 comes out from the scraping port 4 at a constant height while the gap remains, the lower end of the scraping plate 6 rotates backward and upward, and the lower end melts. The solder metal 2 is rotated until it almost contacts the upper surface of the solder metal 2 (see the two-dot chain line in FIG. 3).

As a result, the upper surface of the molten solder metal 2 pushed and raised by the front surface of the advancing scraping plate 6 is connected to the front surface of the scraping plate 6 formed by the abutting body 10 and the upper edge 12 of the scraping opening. The oxide film 15 sneaks downward through the gap and moves to the rear side of the scraping plate 6, and only the oxide film 15 is scraped onto the slide 5 of the scraping port 4.

In the embodiment described above, the front surface of the scraping board 6 is formed so as to be inclined downwardly and rearward, and the front end surface of the abutting body 10 is a substantially vertical plane, and the front surface of the scraping board 6 comes into contact with the lower end of the scraping board 6. Although the distance from the front end surface of the object 10 is made to be large, instead of this,
Even if the scraping plate 6 is made into a vertical flat plate shape and the front end surface of the abutment body 10 is formed into a forward convex curved shape such as a side semicircular shape, the front end surface of the abutment body 10 is the upper end of the scraping port. When in contact with the edge 12, the contact body 10
A gap of an appropriate size is formed between the upper edge 12 and the front surface of the scraping plate 6 at a location other than the above-mentioned portion, and while the gap is maintained, the lower end of the scraping plate 6 is moved backward. You can escape and rotate upwards.

In summary, the present invention provides a scraping plate on one side of the solder tank, which has its lower end immersed in the upper surface of the molten metal to scrape up the oxide film on the upper surface of the solder tank with its top open, in which the solder metal is stored in a molten state. The scraping plate is provided so as to move forward toward the provided scraping opening, and the scraping plate is configured such that its lower end is freely rotatable backward and upward in the opposite direction to the traveling direction, and the scraping plate is configured to move forward toward the provided scraping opening. is provided with an abutting body, and when the scraping plate approaches the upper edge of the scraping port of the solder tank and this part is in contact with the abutting body, the upper edge of the scraping opening and the front surface of the scraping plate so that there is a gap between
The structure allows the molten solder metal to sneak downward through this gap, while scraping only the oxide film out of the solder tank, so when the scraping plate approaches the scraping opening, the contact body While it comes into contact with the top edge of the scraping port, the front surface of the scraping plate other than the contact body does not come into contact with the top edge of the scraping port, and the molten solder metal sinks down and falls through the gap. This eliminates the need for the entire front surface of the scraping plate to hit the upper edge and push out the raised solder metal from the scraping opening, instead of forcing the raised solder metal outward from the scraping opening, as would be the case without this contact member. It has the effect of not wasting solder metal, and the structure for this purpose is extremely simple.

[Brief explanation of the drawing]

The drawings show an embodiment of the present invention, and FIG. 1 is a schematic side sectional view of the device, FIG. 2 is a sectional view taken along the line -- in FIG. 1, and FIG. 3 is an explanatory diagram of the operation. 1... Solder tank, 2... Molten solder metal, 4... Scraping opening, 5... Slide, 6... Scraping plate, 8...
... Drive means, 9 ... Support rod, 10 ... Contact body.

Claims (1)

[Scope of utility model registration request] At the top of a solder tank with an open top that stores solder metal in a molten state, a scraping plate is installed with its lower end immersed in the top surface of the molten metal to scrape off the oxide film on the top surface, and is inserted into a scraping port provided on one side of the solder tank. The scraping plate is configured such that its lower end can be freely rotated backwards and upwards in the opposite direction to the advancing direction, and abutting bodies are provided at appropriate locations on the scraping plate. When the scraping plate approaches the upper edge of the scraping port of the solder tank and this portion is in contact with the contact body, a gap is created between the upper edge of the scraping port and the front surface of the scraping plate. An oxide film removal device for a molten solder tank, which is configured to allow molten solder metal to pass downward through the gap, while scraping only the oxide film out of the solder tank.