JPH02211978A - Method for applying flux - Google Patents

Abstract

PURPOSE:To apply a fixed quantity of flux on a fixed area by dropping a fixed quantity of flux on the transferring surface of an applying jig having a prescribed shape and transferring the flux extended on the transferring surface of the applying jig to a material to be applied. CONSTITUTION:A fixed quantity of flux 25 is applied on the limited area of the material 23 to be applied. A fixed quantity of flux 25 is then dropped on the transferring surface 27 of the applying jig 26 having a prescribed shape. The flux 25 extended on the transferring surface 27 of the applying jig 26 is transferred to the material 23 to be applied. At the time of dropping the flux, the transferring surface of the applying jig is made upward and at the time of transferring, the applying jig is rotated by 180 deg.. By this method, the influence by drying of the flux is avoided.

Description

DETAILED DESCRIPTION OF THE INVENTION (Objective of the Invention) (Industrial Application Field) The present invention relates to a flux application method applied to soldering of electronic devices.

(Prior Art) Conventionally, flux application to a small area when connecting flexible substrates or the like by a solder fusion method has been performed by a dip method, a brush method, a dispense method, a transfer method, or the like.

The dip method is a method in which an object to be coated (hereinafter referred to as a sample) 11 is held by a gripping mechanism 12 and dipped into a flux 13, as shown in FIG.

The brush coating method was applied to sample 11 as shown in FIG.
This is a method of applying flux 13 to a predetermined location using a brush 14.

In the dispensing method, as shown in Figure 6, flux 13 is dropped onto a predetermined location of sample 11 using a dispenser (Note 04 WA-like equipment) 15, and this flux 13 is expanded as shown in (2). This is a method that allows you to

In the transfer method, as shown in FIG.
6 is rotated, and the flux 13 inside this container 16 is stretched into a film of constant thickness using a spatula 17.
As shown in (2), the transfer jig 18 is brought into contact with the film-like flux 13 in the stationary container 16. The flux 13a is peeled off, and as shown in Φ),
This is a method of transferring the flux 13a to the sample 11.

(Problems to be Solved by the Invention) Such conventional flux coating methods have the following problems.

The dip method shown in FIG. 4 cannot be applied while the sample 11 is fixed on a positioning stage, etc.
This method has the disadvantage that the mechanism for pinching and dipping the sample 11 becomes complicated, and flux is also applied to the back side of the sample, which is not necessary. Flux in Zaraani tank 1
Process control is 1 to keep the concentration constant in 3! It has the disadvantage of being sloppy.

The brush coating method shown in FIG. 5 has drawbacks such as shedding of hairs, hardening of the brush due to drying of the flux, and uneven coating.

The dispensing method shown in FIG. 6 has the disadvantage that the shape of the flux applied is dome-shaped, making it difficult to apply it to a minute regular-shaped surface.

The transfer method shown in FIG. 7 has a drawback that the viscosity of the flux in the container 16 changes over time due to drying.

SUMMARY OF THE INVENTION An object of the present invention is to provide a flux application method that solves these conventional problems at once, eliminates the influence of flux drying, and can apply a fixed amount of flux to a small fixed area.

(Structure of the Invention) (Means for Solving the Problems) The invention of claim 1 is a flux application method for applying a fixed amount of flux to a limited area of a workpiece 23. This is a flux application method in which a fixed amount of flux 25 is dropped onto the transfer surface 27 and the flux expanded over the entire surface of the transfer surface 27 of the application jig 26 is transferred onto the object 23 to be coated.

The invention according to claim 2 is the flux application method according to claim 1, in which the transfer surface 27 of the application jig 26 is directed upward when dropping flux, and the application jig 26 is rotated by 180° during transfer. This is a flux application method in which the surface is facing downward.

In the invention of claim 3, when performing the flux application method of claim 1 or claim 2, a transfer surface 27 of a coating jig 26 formed of a resin into which flux does not permeate is applied to the transfer surface 21. This is a flux application method in which flux is expanded along the formed grooves 31.

(Function) In the invention of claim 1, immediately before the flux is transferred to the object 23 by the coating jig 26, fresh flux 2 is applied from a dispenser or the like to the transfer surface 21 of the coating jig 26.
5 can be added dropwise, so there is no effect from the drying of the flux. Furthermore, a fixed amount of flux 25 dropped onto the transfer surface 27 of the coating jig 26 having a certain shape expands over the entire surface of the transfer surface 27 to form a flux film having a certain shape and a certain thickness. By transferring this flux film to the object 23 to be coated, a fixed amount of flux can be applied to a fixed area.

According to the second aspect of the invention, when the object to be coated 23 is located below the coating jig 26, first, the transfer surface 27 of the coating jig 26 is
with the flux facing upward and applying flux 25 to this transfer surface 21.
The flux on the transfer surface 27 is transferred to the object 23 on the lower side by dropping a fixed amount of the flux on the transfer surface 27 and then inverting the transfer surface 27 downward.

According to the third aspect of the invention, since the coating jig 26 is made of a resin that does not allow flux to penetrate, there is no effect of drying of the flux. Flux 25 is spread evenly.

(Example) Hereinafter, the present invention will be explained in detail with reference to the example shown in FIGS. 1 to 3.

As shown in FIG. 1, when applying flux to an object to be coated (hereinafter referred to as a sample) 23 such as a flexible substrate fixed to the recess 22 of the alignment stage 21, a fixed amount of flux is discharged under pressure from the dispenser 24. The flux 25 is dripped onto the fixed-shaped transfer surface 21 facing upward of the coating jig 26 waiting below. This coating jig 26 is attached via an arm 29 to the end surface of a movable body 28 that is capable of horizontal, vertical, and rotational movements.

The coating jig 26 is made of resin that does not allow flux to penetrate, and as shown in FIG.
A groove 31 with a depth of about 1M is provided in the longitudinal direction of the groove 7. Therefore, the flux dropped onto the transfer surface 21 quickly spreads over the entire surface of the transfer surface 27 due to the guiding action of the grooves 31.

Next, when the coating jig 26 is horizontally moved to directly above the sample 23, the movable body 28 is rotated by 180 degrees, as shown in FIG.
Point it downwards and lower it further. As a result, the flux on the transfer surface 27 of the coating jig 26 is transferred and coated onto the sample 23.

After completing the fixed amount application of flux in this way,
The application jig 26 is raised slightly while facing downward, and the movable body 28 is horizontally moved toward the origin.

On the way back to the origin, the transfer surface 27 of the coating jig 26 is rubbed by the brush 41 attached upward to the side surface of the positioning stage 21, and excess flux remaining on the transfer surface 27 is removed.

When the movable body 28 returns to the origin, it rotates 180 degrees and waits with the transfer surface 27 of the coating jig 26 facing upward, as shown in FIG.

Note that if the flux solidification grows at the flux discharge port of the dispenser 24 and the flux discharge flow rate decreases, by adjusting the flux discharge time of the dispenser 24 to be longer, the transfer surface 27 of the application jig 26 can be It is possible to always supply a constant flux to.

The flux application method described above is particularly effective for stably connecting flexible substrates using the solder fusion method, but is not limited thereto.

Furthermore, the invention of claim 1 is not limited to the embodiment in which the coating jig 26 is reversed; for example, when a fixed amount of flux is dropped onto the coating jig 26 facing upward, the coating jig 26 is reversed. It also includes a flux application method in which the flux is moved to the underside of the object to be coated while facing upward without moving the flux to the lower surface of the object to be coated.

(Effect of the invention) According to the invention of claim 1, a fixed amount of flux is dropped onto the transfer surface of a coating jig having a fixed shape, the flux is stretched to a fixed shape and thickness on the transfer surface of the coating jig, and the flux is Since the flux is transferred to the object to be coated, even when applying flux to a small area where conventionally the opening angle was large, a fixed amount of flux can be applied to a fixed area using a coating jig with a fixed shape. Each time a new flux is applied, a fixed amount of new flux is added, so it is not affected by flux drying.

According to the second aspect of the invention, since the transfer surface of the coating jig receives a fixed amount of flux while facing upward and performs flux transfer with the transfer surface facing downward, the coating surface can be easily mounted on the positioning stage. The invention of claim 1 can also be applied to objects.

According to the invention of claim 3, the effect of flux drying can be eliminated by using the coating jig made of a resin that does not allow flux to penetrate, and furthermore, the grooves formed on the transfer surface of the coating jig can eliminate this effect. It is possible to smoothly guide the expansion of the flux dropped onto the transfer surface over the entire surface, and it is possible to ensure uniformity of the flux over the entire surface of the transfer surface.

[Brief explanation of the drawing]

FIGS. 1 and 2 are perspective views showing an embodiment of the flux coating method of the present invention, and FIG.
To) A perspective view during dropping, Figure 2 is a perspective view during transfer,
FIG. 3 is an enlarged perspective view of the coating jig according to the present invention, FIG. 4 is an explanatory diagram showing the conventional dip coating method, FIG. 5 is a perspective view showing the conventional brush coating method, and FIG. 6 is an explanatory diagram showing the conventional dip coating method. A perspective view showing the dispensing method, and FIG. 7 are explanatory diagrams showing the conventional transfer method. No. 23: Object to be coated, 25: Flux, 26: Coating jig, 21: Transfer surface, 31. e,? >, groove.

Claims (3)

[Claims] (1) In a flux application method in which a fixed amount of flux is applied to a limited area of the object to be coated, a fixed amount of flux is dropped onto the transfer surface of a coating jig having a fixed shape, and the flux is spread onto the transfer surface of this coating jig. A flux application method characterized by transferring flux to an object to be coated. (2) The flux application method according to claim 1, characterized in that the transfer surface of the application jig is directed upward when dropping the flux, and the application jig is rotated 180 degrees to bring the transfer surface downward during transfer. . (3) The flux is expanded along the grooves formed on the transfer surface of the application jig, which is made of a resin that does not penetrate the flux, on the transfer surface. 2. Flux application method described in 2.