JPH0314545B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION [Industrial Application Field] The present invention relates to a vapor phase soldering device that performs reflow soldering using latent heat of vaporization in the vapor phase.

[Conventional technology]

Vapor-phase soldering equipment melts the solder interposed between the printed wiring board and the mounted components by the latent heat of vaporization of the vapor phase generated in the steam tank while transporting the printed wiring board, thereby bonding it to the printed wiring board.
It is used to solder mounted components such as ICs.

Conventionally, this type of vapor phase soldering equipment has a liquid tank installed at the bottom of the steam tank, and a liquid such as a fluorine-based inert solvent stored in this liquid tank is evaporated by a heater and then released into the vapor tank. to form a vapor phase.

[Problem that the invention seeks to solve]

However, in the vicinity of the upper opening of the liquid tank, an inlet and an outlet for carrying printed wiring boards, etc. There is a possibility that the phase may flow out from the carry-in port and the carry-out port. Furthermore, the liquid tank may be too large for a small printed wiring board, in which case the thermal efficiency is poor.

The purpose of the invention is to prevent the diffusion of the vapor phase and prevent the vapor phase from flowing out to the outside, and to improve thermal efficiency by changing the opening area at the top of the liquid tank depending on the size of the printed wiring board. There is a particular thing.

[Means for solving problems]

The present invention provides a liquid tank 12 at the lower part of the steam tank 11, evaporates the liquid in the liquid tank 12 to form a vapor phase 41 in the vapor tank 11, and forms a vapor phase 41 in the vapor tank 11.
The mounted component W is soldered to the printed wiring board P by heating and melting the solder interposed between the printed wiring board P inserted in 1 and the mounted component W by the latent heat of vaporization of the vapor phase 41. In the vapor phase soldering apparatus, a pair of adjustment plates 3 are provided above the liquid tank 12 to variably adjust the opening area of the liquid tank.
1 is provided, and this pair of adjustment plates 31 is provided with a mounting part 3 that is moved and adjusted in parallel with the substrate conveyor 21.
2 and mutually opposing nozzle parts 34 provided perpendicularly from this mounting part 32, and this nozzle part 34 is provided with an insertion hole 35 through which the substrate conveyor 21 is inserted. It is.

[Effect]

In the present invention, a pair of adjusting plates 31 are provided at the upper part of the liquid tank 12.
Therefore, the vapor phase 41 is formed between the pair of adjustment plates 31 and is difficult to diffuse to the outside of the steam tank 11. Further, the range of the vapor phase 41 acting on the component mounting board P is changed by adjusting the distance between the pair of adjustment plates 31 according to the size of the printed wiring board P, component density, etc. The pair of adjustment plates 31 adjust the distance between the pair of nozzle parts 34 by adjusting the movement of the mounting part 32 at the board transport level where the printed wiring board P is transported, so that the distance between the pair of adjustment plates 31 is adjusted by adjusting the movement of the mounting part 32. can be accurately limited.

〔Example〕

Hereinafter, the present invention will be explained in detail with reference to embodiments shown in the drawings.

A liquid tank 12 is provided below the steam tank 11, a fluorine-based inert solvent 13 is stored inside the liquid tank 12, and this solvent 13 is heated by a heater 14 disposed inside the liquid tank 12. It is evaporated into the steam tank 11. Further, a carry-in port 15 is provided on the carry-in side of the steam tank 11, and a carry-out port 16 is provided on the carry-out side.
A cooling coil 1 as a cooling section is installed on the inner wall of each
7, 18, and 19 are provided.

Further, a conveyor 21 mainly consisting of a pair of endless chains is disposed in an endless manner via the carry-in port 15, the steam tank 11, and the carry-out port 16.
The printed wiring board P is suspended between the pair of chains, placed thereon, and transported. Electronic components W such as surface-mounted integrated circuits are mounted on this printed wiring board P.

Furthermore, as shown in FIG. 1, a pair of adjustment plates 31 are provided above the liquid tank 12 to variably adjust the opening area of the liquid tank 12.

The adjustment plate 31 is a substantially L-shaped plate member as shown in FIG.
2, this attachment part 32 is provided with a pair of long holes 33, and the vertical part of the L-shaped adjustment plate 31 is a nozzle part 34, and this nozzle part 34 has the conveyor 21 and a pair of elongated holes 33 provided therein. Insertion hole 35 into which the printed wiring board to be transported is inserted
is provided.

Then, the bolt 36 is inserted into the elongated hole 33, inserted into a small hole (not shown) in the plate member of the loading port 15 or the loading port 16, and screwed into the nut 37.
By tightening this bolt, the pair of adjustment plates 31
is fixed.

Then, when the component mounting board P is supplied between the pair of chains at one end of the conveyor 21,
This component mounting board P is transported together with the chain and carried into the carrying-in port section 15, and further carried into the steam tank 11, and then carried into the steam tank 11.
The fluorine-based inert solvent is introduced through the insertion hole 35 between the pair of adjusting plates 34 in the inner side, and passes through the vapor phase 41 of the fluorine-based inert solvent formed between and around the nozzle portions 34 of the pair of adjusting plates 31. At this stage, it is heated to approximately 215°C by the latent heat of vaporization of this vapor phase 41,
This heating causes the printed wiring board P and the mounted components W to
The cream solder interposed between the two is melted, and the leads of the mounted component W are soldered to the printed wiring board P.

The component mounting board P carried out from the carrying out port 16 is taken out from the conveyor 21.

In addition, if the size of the printed wiring board P or the mounting density of the parts W mounted on the board changes, loosen the tightening force of the bolts 36 while the device is at rest, and tighten the pair of bolts within the range of the elongated holes 33. The upper opening area of the liquid tank 12 is variably adjusted by moving and adjusting the adjusting plate 31 to change the interval.

〔Effect of the invention〕

According to the present invention, since a pair of adjustment plates for variably adjusting the opening area of the liquid tank are provided at the upper part of the liquid tank, the pair of adjustment plates prevents the vapor phase evaporated from the liquid tank from diffusing. The leakage of the vapor phase to the outside can be suppressed, and the heating time can be changed by changing the opening area at the top of the liquid tank in response to changes in heat capacity such as the size of the printed wiring board, increasing thermal efficiency. You can improve. In particular, the pair of adjustment plates are formed by a mounting part that is movably adjusted in parallel with the substrate conveyor, and nozzle parts that are provided perpendicularly to the mounting part and face each other, and the nozzle parts include: Since the insertion hole through which the board conveyor is inserted is provided, the distance between the pair of nozzle parts can be adjusted by adjusting the movement of the mounting part at the board transport level where printed wiring boards are transported, and the vapor phase during reflow soldering can be adjusted. You can limit the area as you wish,
The amount of heat applied to the component mounting board can be controlled with high precision.

[Brief explanation of the drawing]

FIG. 1 is a sectional view showing an embodiment of the vapor phase soldering apparatus of the present invention, and FIG. 2 is an exploded perspective view of the main parts thereof. P...Printed wiring board, W...Mounted components, 1
DESCRIPTION OF SYMBOLS 1...Steam tank, 12...Liquid tank, 21...Substrate conveyor, 31...Adjustment plate, 32...Mounting part, 3
4... Nozzle part, 35... Insertion hole, 41... Steam phase.

Claims (1)

[Claims] 1. A liquid tank is provided at the bottom of the steam tank, and the liquid in this liquid tank is evaporated to form a vapor phase in the vapor tank, and the printed wiring board carried in by the board conveyor and mounted in this vapor phase. In a vapor phase soldering device that solders mounted components to a printed wiring board by heating and melting the solder interposed between the components and the components using the latent heat of vaporization of the vapor phase,
A pair of adjustment plates for variably adjusting the opening area of the liquid tank are provided at the top of the liquid tank, and the pair of adjustment plates have a mounting part that moves and adjusts parallel to the substrate conveyor, and a mounting part that moves perpendicularly from the mounting part. 1. A vapor phase soldering apparatus, characterized in that the nozzle portion is formed by mutually opposing nozzle portions provided in the nozzle portion, and the nozzle portion is provided with an insertion hole through which the substrate conveyor is inserted.