JPH0245946B2 - - Google Patents

Description

[Detailed Description of the Invention] [Object of the Invention] (Industrial Application Field) The present invention relates to a vapor phase soldering device, and particularly to a vapor phase soldering device that prevents leakage of vapor to the outside. It has characteristics.

(Prior Art) As shown in FIG. 2, in a vapor phase soldering apparatus, a liquid (fluorinated inert solvent) 13 contained in a liquid reservoir 12 at the bottom of a steam tank 11 is supplied to a heater 14. By being heated and evaporated, the steam tank 1
A saturated vapor phase 15 is formed inside the tank 1, and the latent heat of vaporization of the saturated vapor phase 15 causes the printed wiring board 17 as a work carried into the steam tank 11 by the conveyor 16 and its mounted components 18 to The paste solder (cream solder) in between is reflowed, and the component 18 is reflow soldered to the board 17.

The liquid (fluorinated inert solvent) 13 used in such a vapor phase soldering device is expensive;
It is necessary to prevent the steam from leaking to the outside of the steam tank 11 as much as possible.

Therefore, a duct-shaped workpiece loading port 21 is provided on one side of the steam tank 11, and a duct-shaped workpiece loading port 22 is provided on the other side, and cooling coils are provided between the loading port 21 and the loading port 22. 23, 24
are arranged, and by cooling the inside of the loading port 21 and the loading port 22 by the cooling coils 23 and 24, the region of the saturated vapor phase 15 is limited, and the saturated vapor phase 15 Most of the unsaturated vapor floating around and about to leak to the outside is condensed and liquefied, and collected in the liquid reservoir 12.

(Problems to be Solved by the Invention) However, during operation of this device, leakage of the unsaturated vapor to the outside is not completely prevented. Inside the steam tank 11, from the workpiece loading port 21 to the workpiece loading port 22, there is movement of air due to external convection, etc., and movement of air accompanying the conveyance of the workpieces, so that the saturated vapor phase 15 There is a problem that a part of the unsaturated vapor floating around the moving air leaks outside.

An object of the present invention is to prevent the steam in the tank from leaking to the outside by preventing the movement of air within the steam tank from the workpiece loading port to the workpiece loading port.

[Structure of the invention]

(Means for Solving the Problems) The present invention provides a saturated vapor phase 15 inside the steam tank 11.
is formed, and the workpieces 17 and 18 are transported from the workpiece loading port 21 located on one side of the saturated vapor phase 15 to the workpiece loading port 22 located on the other side of the saturated vapor phase 15. , saturated vapor phase 1
In a vapor phase soldering device in which reflow soldering is performed using the latent heat of vaporization of the saturated vapor phase 15, the saturated vapor phase 15 is placed above the central part of the steam tank 11 corresponding to the top of the saturated vapor phase 15 within a range that does not interfere with the conveyance of the workpiece. A partition plate 31 inserted into the top of the vapor phase 15 is provided.

(Function) The present invention utilizes a saturated vapor phase 15 that is generated from a liquid with a very high specific gravity and can be regarded as a single immobile mass, and a partition plate 31 inserted into a part of this saturated vapor phase 15. Then, the workpiece entrance part 2
1 and the workpiece unloading port 22 are blocked, and the movement of the air in the tank from the loading port 21 to the unloading port 22 is prevented, so that the steam in the tank caused by the movement of the air in the tank leaks to the outside. is prevented.

(Example) Hereinafter, the present invention will be explained in detail with reference to an example shown in FIG. Note that the same parts as in the conventional example shown in FIG. 2 are given the same reference numerals, and the explanation thereof will be omitted.

Steam tank 11 corresponding to the top of saturated vapor phase 15
An intermediate partition plate 31 is provided at the upper center of the saturated vapor phase 15 to the extent that it does not interfere with the conveyance of the printed wiring board 17 as a workpiece and its mounted components 18. Therefore, the space above the conveyor in the steam tank 11 is completely divided into a workpiece loading side and a workpiece unloading side.

The saturated vapor phase 15 is generated from the liquid (fluorine-based inert solvent) 13 with a very high specific gravity, and can be regarded as a single immobile mass that does not move with the air flow that occurs in the steam tank 11. ,
This saturated steam phase 15 and the partition plate 31 inserted into a part of the saturated steam phase 15 constitute a kind of partition wall in the center of the steam tank 11, and extend from the workpiece loading port 21 to the workpiece loading port 22. The tank interior space is blocked off at the center.

Therefore, from the loading port 21 to the loading port 22
This prevents the tank air from moving over the tank, and also prevents the tank steam from leaking out on the tank air. This in-tank steam is mist-like unsaturated steam floating around the saturated steam phase 15.

〔Effect of the invention〕

According to the present invention, by providing a partition plate above the center of the steam tank corresponding to the top of the saturated vapor phase, the partition plate is inserted into the top of the saturated vapor phase within a range that does not interfere with the conveyance of the workpiece. Since the characteristics of the saturated vapor phase are utilized to eliminate the movement of air within the steam tank, it is possible to effectively prevent the steam within the tank from leaking to the outside, which occurs due to the movement of air within the tank.

[Brief explanation of the drawing]

FIG. 1 is a sectional view showing an embodiment of a vapor phase soldering apparatus according to the present invention, and FIG. 2 is a sectional view of a conventional vapor phase soldering apparatus. 11... Steam tank, 15... Saturated vapor phase, 17,
18...Printed wiring board and mounted components as a workpiece, 21...Workpiece loading port, 22...Workpiece loading port, 31...Inner partition plate.

Claims (1)

[Claims] 1 A saturated vapor phase is formed inside the steam tank, and a workpiece is transported from a workpiece loading port located on one side of this saturated vapor phase to a workpiece loading port located on the other side of the saturated steam phase. On the other hand, in a vapor phase soldering machine that performs reflow soldering using the latent heat of vaporization of the saturated vapor phase, there is a space above the center of the steam tank corresponding to the top of the saturated vapor phase in an area that does not interfere with the conveyance of the workpiece. A vapor phase soldering apparatus characterized in that a partition plate is provided at the top of the saturated vapor phase.