JPH0832005A - Lead frame plating equipment - Google Patents

Abstract

(57) [Abstract] [Purpose] To provide a lead frame plating apparatus capable of suppressing the peeling of the plating material. The present invention is a plating apparatus 1 for performing a predetermined plating treatment while continuously feeding a long lead frame 10 in a longitudinal direction thereof into a plating solution 3 in a solution tank 2,
A shield plate 6 for hindering the progress of the plating process is provided around both side ends 10a along the longitudinal direction of the lead frame 10 in the plating solution 3. In addition, the shield plate 6 is provided around both side ends 10a of the lead frame 10 and other portions where plating is unnecessary, or the lead frame 1
It is also a plating apparatus 1 provided with a shielding means which also serves as a transport mechanism of 0.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a plating apparatus for performing a predetermined plating process on a long lead frame, a so-called hoop lead frame.

[0002]

2. Description of the Related Art In electronic parts such as diodes and transistors, a lead frame formed by pressing a thin metal plate is used as a member for mounting chip-shaped elements and for obtaining electrical connection with the outside. The lead frame is
Mainly composed of a die pad portion for mounting a chip-shaped element, a lead portion extended outward from the vicinity of the die pad portion and held by a frame portion serving as a side end, and a sprocket hole for feeding provided in the frame portion Has been done.

To manufacture an electronic component using this lead frame, first, a chip-shaped element is mounted on the die pad portion of the lead frame, and the element and the lead portion are wired by a bonding wire. Next, after the element and the portion of the bonding wire are molded with resin, the lead portion is plated with solder or the like. After the plating treatment, the lead portion is separated from the frame portion and the electrical characteristics are measured as individual devices. Further, particularly when a large number of electronic components are continuously manufactured, a long lead frame, a so-called hoop lead frame is used.

A so-called hoop-shaped lead frame is wound around a reel in units of several tens of meters to several hundreds of meters, and when electronic parts are manufactured, they are continuously fed into the manufacturing apparatus from the reel in order. Processing is done. The same applies to the plating equipment.The long lead frame is sent from the reel to the pretreatment tank, then into the bath containing the plating solution, and after the prescribed plating treatment is performed, it is sent to the posttreatment tank. To be Then, the processed lead frame is taken up by another reel.

[0005]

In such a plating apparatus, since the long lead frame is simply continuously fed into the bath of the plating solution, the plating treatment is performed over the entire metal portion of the lead frame. Will be given. In particular, since electric field concentration occurs in the vicinity of the side end portion of the lead frame during the plating process, the plating thickness at that portion becomes thicker, and the lead frame is easily peeled off. Specifically, the plating material deposited on the surface around the side edges of the lead frame has a thickness two to three times that of the plating material deposited on the surface of the central portion, which makes it very easy to peel off. There is.

When the lead frame after such a plating treatment is fed into the inside of the next measuring device or the like, the gear is bitten into a sprocket hole for feeding provided on the side end portion of the lead frame, or fed. A feeding belt is brought into contact with the side end portion to feed it. Therefore, there is a disadvantage that the plating material is easily peeled off due to the contact between the feed mechanism and the side end portion of the lead frame to which the plating material is easily attached, and the dust is scattered in the measuring device.

Originally, such a side end portion of the lead frame is one of the portions which need not be subjected to plating treatment, and the plating solution is wastefully used by attaching the plating to this portion. In addition, it is necessary to flow an electric current for plating more than necessary, which causes unnecessary cost increase.

[0008]

SUMMARY OF THE INVENTION The present invention is a lead frame plating apparatus which has been made to solve such problems. That is, the present invention is a plating apparatus for performing a predetermined plating treatment while continuously feeding a long lead frame in the longitudinal direction thereof into a plating solution in a solution tank,
A shield means for hindering the progress of the plating process is provided around both end portions in the plating solution along the longitudinal direction of the lead frame.

Further, the present invention is also a lead frame plating apparatus in which the shielding means is provided around both side end portions of the lead frame and other portions not requiring plating, and the shielding means also serves as a lead frame transport mechanism.

[0010]

In the plating apparatus of the present invention, since the shielding means is provided around both end portions along the longitudinal direction of the lead frame in the plating solution in the bath, the shielding means allows the electric field in the plating solution and the plating to be performed. The flow of liquid is blocked,
The deposition rate of the plating material around the both ends of the lead frame is significantly reduced. For this reason, the plating material is hardly deposited around the both end portions of the lead frame, and even if the feed mechanism in the apparatus in the step after the plating treatment comes in contact with the both end portions of the lead frame, it does not fall off.

Further, by providing the shielding means around both end portions of the lead frame and around other portions not requiring plating, the plating process is performed only on the required portion of the lead frame, and the plating solution and the current amount are wasted. Can be suppressed. Further, by using both the shielding means and the transport mechanism, it is possible to simultaneously feed the lead frame into the plating solution and shield the unnecessary plating portion.

[0012]

Embodiments of the lead frame plating apparatus of the present invention will be described below with reference to the drawings. FIG. 1 is a schematic view illustrating a plating apparatus of the present invention, FIG. 2 is a side sectional view of the plating apparatus of the present invention, and FIG. 3 is a schematic plan view showing a lead frame to be plated. As shown in FIG. 3, the lead frame 10 to be plated is a long lead frame, and leads that are electrically connected to an element (not shown) sealed in the package 12 are formed. The portion 10b is held by the frame portions 10c at both ends. Also,
The frame portion 10c is provided with a sprocket hole 10d, so that the lead frame 10 can be fed in the longitudinal direction by engaging a gear of a feed mechanism provided in various manufacturing apparatuses with the sprocket hole 10d. Has become.

As shown in FIG. 1, the plating apparatus 1 according to the present embodiment is one in which such a long lead frame 10 is sequentially fed to perform a plating process such as solder plating. To perform the plating treatment, the lead frame 10 wound on the reel 11a is sequentially fed in the longitudinal direction, and pretreatment such as cleaning and degreasing is first performed in the pretreatment tank 20 and then the liquid tank 2
After the lead frame 10 is fed into the plating solution 3 therein to perform a predetermined plating treatment, post-treatment such as cleaning, neutralization and drying is performed in the post-treatment tank 30. The plated lead frame 10 is wound on another reel 11b and passed to a device for performing the next step, for example, a measuring device.

The plating apparatus 1 of this embodiment has a liquid tank 2 for containing a plating solution 3, an anode 4 arranged in the plating solution 3 and serving as an anode, and a liquid tank 2 for feeding the lead frame 10. It is provided with a pantograph 5 for contacting at the inlet portion to make the lead frame 10 a cathode, and further with a shield plate 6 for covering the periphery of both side ends 10a of the lead frame 10 in the plating solution 3.

As shown in FIG. 2, the shield plate 6 has a generally U-shaped cross section and is arranged slightly wider than the width of the lead frame 10. For example, by setting the distance between the shield plate 6 and the lead frame 10 to be about 0.2 mm to 0.4 mm, the electric field from the anode 4 is applied to the side end 10.
It is possible to suppress the concentration in the portion a and to suppress the inflow amount of the plating solution 3.

Specifically, for example, when solder is deposited on the surface of the central portion of the lead frame 10 with a thickness of 5 to 10 μm, the surface around the side ends 10a covered with the shield plate 6 is 1 to 2 μm. It is about the thickness. By continuously feeding the long lead frame 10 between the shield plates 6, the thickness of the plating material deposited around the both side ends 10a of the lead frame 10 can be extremely reduced.

As the material of the shield plate 6, resin, metal, ceramics or the like may be used, but it is particularly preferable to use fluororesin having strong chemical resistance. Further, the distance between the shield plate 6 and the lead frame 10 is not limited to the value shown above, and may be any distance that can reduce the deposition rate of the plating material at the side end 10a.

The lead frame 1 covered with the shield plate 6
The periphery of the side edge 10a of 0 is the frame portion 10c of the lead frame 10, and the sprocket hole 10d described above is provided therein. In the plating apparatus 1 according to this embodiment, since the plating material deposited on the frame portion 10c of the lead frame 10 is small, when the lead frame 10 is fed by the apparatus in the step after the plating process, the feeding mechanism of the apparatus has a frame portion. The plating material will not come off even if it comes into contact with 10c.

That is, by the action of the shield plate 6, both end portions 10a of the lead frame 10 and the frame portion 10c.
Since the plating treatment is not performed unnecessarily thick, the plating material will not be peeled off even if there is some contact. Therefore, even if the feed mechanism of the manufacturing apparatus comes into contact with the sprocket hole 10d and the frame portion 10c, the plating material is not peeled off and is not scattered as dust in the manufacturing apparatus.

FIG. 4 is a schematic plan view showing another lead frame. This lead frame 10 'is capable of arranging two rows of elements (not shown) and a package 12 in the width direction (widthwise direction) thereof, and the lead frame 10' is located between the two rows at substantially the center thereof. Is provided with a frame portion 10e for holding the lead 10b extending downward in the upper row in the drawing and the lead 10b extending upward in the lower row in the drawing.

FIG. 5 shows such a lead frame 10 '.
FIG. 6 is a side sectional view showing another example (No. 1) of the plating apparatus corresponding to FIG. In this lead frame 10 ', the frame portions 10c on both sides in contact with the feed mechanism in the device in the step after the plating treatment are the portions that do not require the plating treatment and are provided substantially in the center, as described above. The frame portion 10e also becomes an unnecessary portion for plating. That is, these parts are the parts that will eventually be cut off, and there is no need to perform plating.

Therefore, the plating apparatus 1 shown in FIG. 5 is provided with a shield plate 6 for covering the periphery of both side ends 10a of the lead frame 10 ', and also with a shield plate 62 for covering the periphery of the frame portion 10e. These shield plates 6, 6
2 reduces the amount of plating material deposited around the both ends 10a of the lead frame 10 ', that is, on both sides of the frame 10c and the substantially central frame 10e. That is, it becomes possible to deposit a prescribed amount of the plating material only on the portion where the plating treatment is necessary and reduce the amount of deposition on the other portions where the plating treatment is unnecessary.

As a result, as described above, it is possible to obtain an effect that the feeding mechanism of the lead frame 10 'can be prevented from coming into contact with the periphery of both side ends 10a and the plating material from peeling off, and an unnecessary portion can be obtained. Since the plating treatment is not performed, it is possible to obtain the effect of suppressing the consumption of the plating solution 3 and the consumption of the current supplied from the anode 4.

In the lead frame 10 'shown in FIG. 4, two rows of elements (not shown) and the package 1 are arranged in the width direction.
I have shown that 2 can be arranged, but in addition to this, 3 rows and 4
The same applies even if the elements (not shown) in a row and the package 12 can be arranged. Even in such a case, if the shield plates 6 and 62 are provided around the frame portions 10c and 10e, which are portions that do not require plating, the required minimum amount of plating deposition will suffice.

Next, another example (No. 2) of the plating apparatus 1 of the present invention will be described with reference to FIG. 6 which is a schematic perspective view. This plating apparatus 1 includes a shield plate 6 that covers the periphery of both side ends 10a of a lead frame 10 fed into a plating solution 3 in a solution tank 2.
(See FIG. 1) is a conveyor belt 61 of the lead frame 10.
It is also used as.

In such a plating apparatus 1, the long lead frame 10 can be fed into the plating solution 3 by the conveyor belt 61 and subjected to a predetermined plating treatment. Further, the conveyor belt 61 is the lead frame 10.
Feeding is performed by making contact with the periphery of both side ends 10a, that is, the frame portion 10c of the lead frame 10 shown in FIG. In other words, the contact of the transport belt 61 prevents the plating process from being performed around the both side ends 10a of the lead frame 10 in contact with the feed mechanism in the device in the step after the plating process, and the plating material does not deposit. become. This prevents the plating material from peeling off from this portion even if the feeding mechanism comes into contact.

Further, the lead frame 1 as shown in FIG.
In the case of 0 ', the conveyor belt 6 is provided around both side ends 10a.
1 may be arranged and brought into contact with each other for feeding, and the shielding plate 62 may be arranged around the frame portion 10e at the substantially center. Instead of the shield plate 62, a conveyor belt 61 as shown in FIG. 6 may be arranged so as to be in contact with the frame portion 10e for feeding.

Further, in the case of using the shield plate 6 having a substantially U-shaped cross section as shown in FIGS. 2 and 5, which covers the periphery of both side ends 10a of the lead frames 10 and 10 ', these shield plates 6 are used. The lead frame 10 as a guide,
10 'may be sent. That is, these shield plates 6 can prevent problems such as slack and undulation when the long lead frames 10 and 10 ′ are fed in the plating solution 3.

[0029]

As described above, the lead frame plating apparatus of the present invention has the following effects. That is, in the plating apparatus of the present invention, the deposition amount of the plating material in this portion can be remarkably reduced by the shield plates that cover the periphery of both end portions of the lead frame in the plating solution. This prevents the plating material from peeling off even if the feeding mechanism in the device in the step after the plating treatment comes into contact with the periphery of the side end portion of the lead frame, and the generation of dust can be suppressed. Further, since it is possible to suppress the plating material from depositing on the unnecessary portion, it is possible to reduce the consumption of the plating solution and the consumption of the current for the plating process. Moreover, because the power supply can be reduced,
It is also possible to contribute to downsizing of the plating apparatus.

[Brief description of drawings]

FIG. 1 is a schematic diagram illustrating a plating apparatus of the present invention.

FIG. 2 is a side sectional view of a plating apparatus.

FIG. 3 is a schematic plan view showing a lead frame.

FIG. 4 is a schematic plan view showing another lead frame.

FIG. 5 is a side sectional view for explaining another example (No. 1).

FIG. 6 is a schematic perspective view illustrating another example (2).

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Plating apparatus 2 Liquid tank 3 Plating liquid 4 Anode 5 Pantograph 6 Shielding plate 10, 10 'Lead frame 10a Side end 11a, 11b Reel 20 Pretreatment tank 30 Posttreatment tank 61 Conveyor belt

Claims (3)

[Claims] 1. A plating apparatus for performing a predetermined plating treatment while continuously feeding a long lead frame in a plating solution in a liquid tank in a longitudinal direction thereof, wherein the lead frame in the plating solution is A lead frame plating apparatus, characterized in that shielding means for preventing the progress of the plating process is provided around both side ends along the longitudinal direction. 2. The lead frame plating apparatus according to claim 1, wherein the shielding means is provided around both side end portions of the lead frame and around other plating unnecessary portions. 3. The lead frame plating apparatus according to claim 1, wherein the shield means also serves as a transport mechanism for the lead frame.