JPH08340077A - Method for removing solvent - Google Patents

Abstract

PURPOSE: To provide a method by which a solvent adhering to a strip type lead frame can be easily and inexpensively drained. CONSTITUTION: In a method for removing solvent, a solvent adhering to a strip type lead frame 1 is removed in a housing case 2 by sucking the solvent by means of a suction blower while high-pressure air is blown upon the lead frame 1 from an air nozzle 3 connected to a high-pressure blower 7. Namely, the solvent is removed in the case 2 airtightly sealed with an upper cover section 8 which can be expanded and contracted in the horizontal direction and lower suction hood 5 by simultaneously performing the blowing of the high- pressure air and sucking of the solvent and moving the nozzle 3 in the horizontal direction.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for draining a strip-shaped lead frame from a solvent, and after cleaning the strip-shaped lead frame of a transistor or an IC with degreasing and cleaning, a cleaning solvent liquid adhering to the lead frame is placed in an airtight storage case. The present invention relates to a solvent liquid draining method for draining liquid with.

[0002]

2. Description of the Related Art A conventional lead frame has a die pad, a central portion for mounting an IC element, and a plurality of outer leads connected to electrodes on the IC element, which are continuously formed. Such leadframes are made of iron,
With a strip material such as copper or its alloy, the central portion to which the IC element is attached and the unnecessary portion of the wide side edge bar are punched out with a press die to form an outer lead, and the central portion and the outer lead are connected by a connector wire. It is configured by.

As described above, since the lead frame punched by the press die has the press oil attached thereto, it is degreased and washed to remove it. At that time, if the used solvent is dried while adhering to the product, the drying time becomes long, the cleaning solvent liquid is consumed, and the product quality deteriorates. Further, in the case of a flammable solvent liquid, the safety deteriorates.

Then, various conventional draining and drying methods will be described with reference to FIGS. 5 to 7 for a strip type lead frame.

FIG. 5 is an explanatory view of an air blow method which is one method of a conventional liquid draining drying method, FIG. 6 is an explanatory view of a vacuum drying method which is one method of a conventional liquid draining drying method, and FIG. It is explanatory drawing of the suction method which is one method of the conventional drainage drying method.

In FIGS. 5, 6 and 7, 1 is a strip type lead frame, 2 a is a cleaning case, 3 is an air blow nozzle,
4 is a high pressure blower, 5 is a suction hood, 11 is a closed container, 1
2 is a vacuum pump.

In FIG. 5, (a) shows the front surface of the air blow method and (b) shows the side surface of the air blow method. As shown, the strip-shaped lead frame 1 to which the solvent in the cleaning case 2a adheres. On the other hand, it is a method in which high pressure air is blown from a plurality of air blow nozzles 3 connected to the high pressure blower 4 from the upper part to remove and discharge the solvent. The air blow nozzle 3 is often a movable type that reciprocates at a uniform speed.

In the vacuum drying method shown in FIG. 6, the cleaning case 2a accommodating the strip-shaped lead frame 1 is entirely covered with a closed container 11.
It is a method in which the adhering solvent is stored in a high vacuum and the evaporated solvent vapor is exhausted by the vacuum pump 12.

In the suction method shown in FIG. 7, the cleaning case 2a accommodating the strip-shaped lead frame 1 and the suction hood 5 are airtightly joined to each other, and the suction blower 7 connected to the suction port of the airtight suction hood 5 is used. It is a method of sucking and discharging the attached solvent.

[0010]

The above-mentioned various conventional liquid draining methods have the following problems.

The air blow method is a method of blowing off the adhering solvent with the mechanical energy of high-pressure air. Although the solvent on the surface of the strip-shaped lead frame can be removed, the solvent adhering between the lead frames can be easily removed. Cannot be removed.
In order to remove this solvent, it is necessary to increase the blowing speed of the high-pressure air, the high-pressure blower has to have a large capacity, and there is a problem that the equipment cost is high.

In the vacuum drying method, not only is the equipment cost of a closed container, a vacuum pump, etc. large, but it is not suitable for mass production due to the batch process, and when the adhering solvent evaporates, the latent heat of evaporation leads to lead. When the frame cools and its temperature drops, evaporation stops.
There was a problem that it had to be heated to -80 ° C, which was costly and troublesome.

In the suction method, since the suction is carried out from below the cleaning case through the air-tight suction hood, the solvent adhering to the lower portion of the lead frame can be easily removed, but the solvent adhering to the upper and middle portions is difficult to remove. There was a problem.

A method using both the air blowing method and the suction method is conceivable. However, since the suction hood must be hermetically closed in the suction method, a blow nozzle for blowing high pressure air is also provided in the air blowing method. The top of the leadframe needs to be airtight. If the blow nozzle is fixed, the airtight structure on the upper part of the lead frame is relatively easy, but high-pressure air will be blown out from one place, so if the blower capacity is not large, There is a problem that it is difficult to provide mechanical energy for blowing off the adhering solvent.

The present invention has been made in order to solve the above-mentioned problems of the prior art, and incorporates the advantages of the air blow method and the suction method into a simple and inexpensive strip-shaped lead frame in a container having an airtight structure. Air blow from the top, at the same time,
It is an object of the present invention to provide a method for draining a solvent that sucks from a lower portion and drains the attached solvent reliably.

[0016]

In order to achieve the above object, the structure of the present invention relating to a solvent liquid draining method is such that a solvent attached to a strip-shaped lead frame is blown with high pressure air from an air nozzle connected to a high pressure blower. It is a solvent liquid draining method in which it is sucked with a suction blower and drained in the storage case, and the spraying and the suction are performed at the same time, the air nozzle is moved in the horizontal direction, and the horizontal upper and lower cover is expandable. It is characterized in that the liquid is drained in a storage case having an airtight structure in which a part and a lower suction hood are attached.

[0017]

The function of each of the above technical means is as follows.

According to the structure of the present invention, high-pressure air is blown from the air nozzle connected to the high-pressure blower and is simultaneously sucked by the suction blower to move the air nozzle in the horizontal direction, so that the upper cover portion which can be expanded and contracted in the horizontal direction is formed. Since the solvent attached to the strip-shaped lead frame is drained in the attached airtight structure storage case, it is possible to remove all the solvent attached to the surface, the middle part, the lower part and between the lead frames of the strip-shaped lead frame. Further, the spraying from the air nozzle and the suction of the suction blower act synergistically to further strengthen the function of removing the adhering solvent.

[0019]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of the present invention will be described below with reference to FIGS.

FIG. 1 is an explanatory view of a liquid draining device used in a solvent liquid draining method according to an embodiment of the present invention, and FIG. 2 is shown in FIG.
4 is an explanatory view of an example of an expandable cover of the liquid draining device of FIG. 3, FIG. 3 is an explanatory view of another example of the expandable cover of the liquid draining device of FIG. 1, FIG.
FIG. 2 is an enlarged explanatory view of an airtight structure of a stretchable cover in the liquid draining device of FIG. 1. In the figure, the same reference numerals as those in FIGS. 5 and 6 are the same parts, and therefore the repetitive description will be omitted and only new reference numerals will be described. 2 is a washing case, 6 is an upper lid, 8 is a cover, 9 is a bellows type cover, 10 is a splice plate type cover, 13
Is the drive chain.

In FIG. 1, (a) is a front view of a liquid draining device used in the solvent liquid draining method according to the present invention.
(B) is a side view of the liquid draining apparatus used for the solvent liquid draining method according to the present invention.

A suction hood 5 is airtightly joined to the lower portion of the cleaning case 2 in which the strip lead frame 1 is housed, and an upper lid 6 is airtightly joined to the upper portion thereof. A blower 7 is connected to the suction hood 5 to suck air.

A plurality of air nozzles 3 that can move horizontally at a constant speed are attached to the upper lid 6, and a high pressure blower 4 is connected to the plurality of air nozzles 3.

A cover 8 is attached to the upper lid 6 so as to be expandable and contractible while maintaining airtightness even when the plurality of air nozzles 3 are horizontally moving at a constant speed.

The air nozzle 3 blows high-pressure air onto the strip lead frame 1 in the cleaning case 2 located below the tip of the air nozzle 3 while the strip lead frame 1 is being blown.
It moves upwards in the horizontal direction at a constant speed. By the function of the elastic cover 8, the cleaning case 2 and the upper lid 6 are
In addition, the suction hood 5 is kept airtight,
The suction can effectively remove the adhering solvent.

The specific structure of the expandable cover 8 is as follows.
It is shown as a bellows type cover in FIG. 2 and as a slide plate type cover in FIG.

In FIG. 2, 9 is a bellows type cover,
(A) is an explanatory view of a state where the bellows are contracted, (b) is an explanatory view of a state where the bellows are extended, and (c) is a side view.

In FIG. 3, 10 is a slide plate type cover, (a) is an explanatory view of the slide plate in a contracted state, (b) is an explanatory view of the slide plate in an extended state, and (c) is a side view. Is.

Next, a specific example of the airtight structure in the case where the bellows type cover 9 is used as the expandable cover 8 will be described with reference to FIG. 4A is an enlarged plan view of the airtight structure of the expandable cover, and FIG. 4B is an enlarged sectional view of the airtight structure of the expandable cover.

As shown in the drawing, a bellows type cover 9 is attached in the upper lid 6. That is, both lateral surfaces of the bellows-type cover 9 are airtightly attached and fixed to both lateral surfaces of the upper lid 6. Both sides of the bellows-type cover 9 in the longitudinal direction are attached so as to maintain airtightness while sliding on the wall surface of the upper lid 6 in the longitudinal direction.

A mounting housing having an air nozzle 3 is arranged substantially in the center of the bellows type cover 9 so as to divide the bellows type cover 9 into two parts. The bellows-type covers 9 are attached airtightly. A drive chain 13 is connected to both ends of the mounting case of the air nozzle 3 so as to move horizontally in the left and right in the figure.

When the air nozzle 3 moves horizontally to the left and right, the bellows of the bellows type cover 9 expands and contracts as shown in FIGS. 2 (a) and 2 (b) to maintain airtightness with the upper lid 6. To do. In this way, the inside of the cleaning case 2 is kept airtight, air is blown from the upper portion, and at the same time, suction from the lower portion works effectively to drain the attached solvent.

Although the bellows type cover 9 has been described above, the same applies to the slide plate type cover 10.

[0034]

As described in detail above, according to the configuration of the present invention, the advantages of the air blow method and the suction method are introduced,
A strip-shaped lead frame housed in a simple and inexpensive airtight container is air blown from the top and at the same time sucked from the bottom to reliably drain the adhering solvent, improving quality and shortening the draining time. It is possible to provide a method for draining a solvent.

[Brief description of drawings]

FIG. 1 is an explanatory diagram of a liquid draining device used in a solvent liquid draining method according to an embodiment of the present invention.

FIG. 2 is an explanatory diagram of an example of an expandable cover of the liquid draining device of FIG.

FIG. 3 is an explanatory view of another example of the expandable cover of the liquid draining device of FIG.

FIG. 4 is an enlarged explanatory view of an airtight structure of a telescopic cover in the liquid draining device of FIG.

FIG. 5 is an explanatory diagram of an air blow method, which is one method of a conventional liquid draining and drying method.

FIG. 6 is an explanatory diagram of a vacuum drying method which is one method of a conventional liquid draining drying method.

FIG. 7 is an explanatory diagram of a suction method, which is one of the conventional liquid draining and drying methods.

[Explanation of symbols]

 1 Strip Lead Frame 2, 2a Cleaning Case 3 Air Blow Nozzle 4 High Pressure Blower 5 Suction Hood 6 Top Lid 7 Suction Blower 8 Cover 9 Bellows Type Cover 10 Slide Plate Type Cover 11 Sealed Container 12 Vacuum Pump 13 Drive Chain

Claims (1)

[Claims] 1. A solvent attached to a strip-shaped lead frame,
A method of solvent drainage in which high-pressure air is blown from an air nozzle connected to a high-pressure blower and is sucked by a suction blower, and liquid is drained in the storage case.The spraying and the suction are performed simultaneously, and the air nozzle is horizontally A method of draining a solvent, which comprises moving and draining in a storage case having an airtight structure in which an upper cover portion which is elastic in a horizontal direction and a lower suction hood are attached.