JPH0257467B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION [Object of the Invention] (Field of Industrial Application) The present invention relates to a vapor phase soldering apparatus having a feature of a liquid recovery system.

(Prior Art) As shown in FIG.
2 is provided, and a vapor phase 15 is formed in the vapor tank 11 by evaporating the liquid (fluorine-based inert solvent) 13 housed inside the liquid tank part 12 with a heater 14, A carry-in port 16 provided on one side of the steam tank 11 for this vapor phase 15
Printed wiring board 1 as an object to be soldered
7 is carried in, the board-mounted components are reflow soldered to the board 17 using the latent heat of vaporization of the vapor phase 15, and the parts are soldered externally to the board 17 through the outlet 18 provided on the other side of the steam tank 11. A cooling coil 19 is provided inside the carrying-in port 16 and the carrying-out port 18, and the condensing action of the cooling coil 19 prevents the vapor phase 15 from leaking to the outside. . However, the cooling coil 19 alone is not sufficient to prevent the vapor from leaking out.

Therefore, conventionally, a liquid recovery system 21 shown in FIG. 2 has been provided. This liquid recovery system 21 sucks steam into the condensation tank 23 from near the openings of the carry-in port 16 and the carry-out port 18 through a steam introduction hose 22, and the vapor is condensed into a coil (an evaporator in a refrigeration cycle). The air is condensed and liquefied in the condensing coil 24, and the liquid component is removed by the condensing coil 24. The air is forced to the outside through an exhaust pipe 25 by a fan. The liquid 13a dripped from the condensing coil 24 and accumulated in the tank 23 is circulated and supplied to the liquid tank section 12 via a liquid supply pipe 28 by a pump 27.

(Problems to be Solved by the Invention) The steam introduced into the condensation tank 23 contains mist with large particle diameters.

A large amount of these mist particles adhere to the condensing coil 24, lowering the steam condensing efficiency (liquid recovery efficiency) of the condensing coil 24, and causing a problem that a large amount of steam is contained in the exhaust gas to the outside. . This liquid 13 that becomes vapor is very expensive.

An object of the present invention is to improve the liquid recovery efficiency in a vapor phase soldering apparatus.

[Purpose of the invention]

(Means for Solving the Problems) The present invention evaporates the liquid 13 contained in the liquid tank portion 12 of the steam tank 11 to form a vapor phase 15 in the vapor tank 11, and Soldering items 17
The vapor phase 15 carries in flow soldering using the latent heat of vaporization that the vapor phase 15 has, and the vapor sequentially generated in the vapor tank 11 is introduced into the condensation tank 23 and liquefied, and the liquid 13a is transferred to the liquid tank section 12. In this vapor phase soldering apparatus, a mist removing body 32 for removing mist particles in the vapor is provided in the vapor introduction section 22 to the condensing tank 23.

(Function) The present invention provides the steam introduction section 22 from the steam tank 11.
When steam is introduced into the condensing tank 23 through the above, mist particles contained in the steam are collected from the steam by the mist removing body 32 and immediately fall to the lower part of the condensing tank 23, and the remaining steam is removed. only that amount is condensed in the tank 23.

(Example) Hereinafter, the present invention will be explained in detail with reference to an example shown in FIG. Note that the vapor phase soldering device and the liquid recovery system are the same as those shown in FIG. 2, so illustration and description thereof will be omitted.

A steam introduction hose 22 as the steam introduction section is connected to pipe connection sections 31 provided on the left and right side surfaces of the condensation tank 23, and a mist removal body 32 is provided inside this hose 22.

As the mist removing body 32, a material such as a fine wire mesh is filled inside the hose 22.

Then, the mist particles (large particle diameter) in the steam easily collide with obstacles, and even without cooling, they are easily caught by the obstacles and separated from the steam flow. At the stage where steam is sucked into the condensation tank 23 from near the openings of the carry-in port 16 and the carry-out port 18 through the steam introduction hose 22, mist particles contained in the steam are captured by the mist remover 32. It is separated from the steam flow and quickly falls through the pipe connection 31 to the lower part of the condensation tank 23. On the other hand, only the remaining fine vapors that cannot be captured by the mist remover 32 come into contact with the condensing coil 24 and the surface of the coil 24 when moving toward the exhaust pipe 25 in the upper part of the condensing tank 23. It is condensed at the coil surface, drips from the coil surface, and accumulates in the lower part of the tank 23.
Then, only air is exhausted to the outside through the exhaust pipe 25.

The mist removing body 32 is not limited to the wire mesh of the embodiment, but may be any other material as long as it allows steam to pass through and acts as an obstacle for mist particles.

〔Effect of the invention〕

According to the present invention, since the mist removing body for removing mist particles in the steam is provided in the steam introduction part to the condensing tank, the mist particles contained in the steam are collected by the removing body before entering the condensing tank. do,
Only the remaining vapor content can be effectively condensed in the condensation tank, thereby increasing the liquid recovery efficiency.

[Brief explanation of the drawing]

FIG. 1 is a cross-sectional view showing one embodiment of the present invention, and FIG.
The figure is a sectional view of a vapor phase soldering device. 11... Steam tank, 12... Liquid tank section, 13... Liquid, 15
...vapor phase, 17...printed wiring board as an object to be soldered, 22...steam introduction hose as a steam introduction part, 23...condensation tank, 32...mist removal body.

Claims (1)

[Claims] 1. The liquid contained in the liquid tank part of the steam tank is evaporated to form a vapor phase in the steam tank, and the objects to be soldered are carried into this vapor phase and reflow soldering is performed using the latent heat of vaporization of the vapor phase. In a vapor phase soldering apparatus, the steam sequentially generated in the steam tank is introduced into a condensation tank and liquefied, and the liquid is circulated to the liquid tank. A vapor phase soldering device characterized by being provided with a mist removing body for removing mist particles therein.