JPH0791678B2 - Strip-shaped member plating equipment - Google Patents

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a transfer device for continuously feeding a strip-shaped member typified by, for example, a lead frame to a processing device such as plating, and a plating device incorporating the transfer device. It is a thing.

[0002]

2. Description of the Related Art A lead frame plating apparatus to which the present invention is typically applied will be described below.

As shown in FIG. 7, the lead frame 1
Is a strip-shaped member punched out from a long metal ribbon and transfer-molded to cover an IC circuit and the like with a plastic package 2. A large number of semiconductor devices are composed of a package portion and a lead wire portion extracted from the package portion. It is a semi-finished electronic component that is continuously installed. Then, the lead wire portion is plated for the purpose of improving solderability of the semiconductor device, improving corrosion resistance, and the like.

In the conventional plating treatment for this purpose, a rack having a net-like plane shape made of a conductive material and having a large number of protrusions formed thereon is used to form a lead frame.
It was usual to support them so as to sandwich them up and down at several places, and to mount a large number (for example, 100) of them in one rack, and to immerse them in a plating bath for electroplating.

In addition, an apparatus of the type in which the member is suspended from a conductive endless belt 10 that rotates endlessly and the member is immersed in a plating bath disposed in the middle of the rotation path of the endless belt has also been proposed. There is. The method of directly suspending the object to be processed with an endless belt is preferable because a mechanical operation mechanism is easily adopted, and the suspension is performed by, for example, a clip type device or an endless metal plate as shown in FIG. A number of slits in the width direction are formed on the belt 10 to form a strip-shaped lead frame 1
There is known a device using an endless belt in which a large number of thin tongue pieces 11 which are elastically engaged with each other on the front and back sides are formed in a comb shape.

In the endless belt 10 having the latter comb-shaped tongue piece 11, the engaging portion 12 at the tip of the tongue piece easily engages and disengages from the front surface or the back surface of the lead frame 1 and can grip it. For example, it is provided in the following structure. That is, a plurality of tongue pieces 11 continuously provided in the rotating direction of the endless belt 10 are divided into two groups, and adjacent tongue pieces 11 are provided so as to engage with the surfaces of the lead frame 1 opposite to each other. And every other first
A tongue piece 11a of one group and a tongue piece 11b of every other second group are provided with protrusions 13a and 13b for opening / closing operation which are bent on opposite sides, and a group of several tongues that are continuous. By pressing these protrusions 13a, 13b of the pieces from the outside, the tip engaging portions 12a, 12b of these tongue pieces are pressed.
A structure in which a gap is formed between the two in the thickness direction, the lead frame 1 is inserted into this gap, and then the pinching pressure from the outside is released, and the lead frame is held by the elastic restoring force of these tongue pieces. By using the endless belt 10 having such a configuration, the endless belt 10 can directly suspend the strip-shaped member such as the lead frame 1.

By the way, in equipment for plating a large amount of products such as the lead frame 1, the work in each step in the process is mechanical, not manual.
Needless to say, it is desirable to be able to automatically and continuously perform the treatment, and this is also desirable for the above-mentioned plating treatment step.

The method using the endless belt is more suitable for mechanization than the method using the mesh rack described above. Suspending the lead frame and immersing it in the plating bath As a method of suspending each lead frame by mechanical means on the endless belt, for example, many lead frames are stored in a magazine rack. , A transfer device of the type in which lead frames are taken out from the rack one by one using a gripping hand, a suction hand, etc., and are carried to a position where they are suspended on an endless belt and suspended (Japanese Patent Laid-Open No. 2-27).
7800).

The method using the endless belt is considered to be a preferable method from the following points. That is, the thickness of the plating layer applied to the lead frame by the above-described plating treatment is generally required to be about 7 to 8 μm, although it varies depending on the type. If the unevenness of the plating thickness is large, it is necessary to set the plating processing time long because it is necessary to satisfy the above-mentioned required specifications even for the product with the minimum plating thickness, and the productivity cannot be increased. In addition, a product with an unnecessarily large plating thickness is produced, and the waste of plating material increases. Therefore, it is required in this type of industrial plating process to prevent the unevenness of the plating thickness as much as possible, but in the plating method of the type using the mesh rack described above, the unevenness of the current distribution in the rack is caused. generally it which may lead to uneven thickness of about ± 40% have been inform <br/> for likely to occur, but its improvement is desired, the plating apparatus of the endless belt type, one by belt If you can hang each lead frame securely, the uneven plating will be ± 10.
% Or less.

[0010]

Therefore, the inventor of the present invention has made extensive studies on an apparatus using an endless belt suitable for the lead frame plating treatment as described above, and has completed the present invention.

That is, in the case of plating a large number of products, it is natural that a certain plating treatment is desired for quality control as described above, but in the above-mentioned type of apparatus in which the lead frame is suspended on the endless belt. However, if the amount of grip of the lead frame 1 by the endless belt is not constant, there is a problem in that the suspension is not performed securely and the lead frame 1 falls off, or the suspension (holding) posture becomes unstable, and the plating process becomes incomplete. It is not always easy to avoid that problem.

For example, the lead frame to be plated is not always limited to a single type with a fixed standard, and even the same type of lead frame has manufacturing tolerances in terms of dimensions and the like, which causes the above problems. easy. In order to avoid this, for example, it is conceivable to place the lead frame at a predetermined reference position and grasp it with a gripping hand, etc. However, in this case, the lead frame is taken out from the magazine rack and set to the reference position. Further, a mechanism or a device for accurately placing the transfer device is required, and the transfer device is duplicated and complicated, and adjustments when handling lead frames of different sizes are troublesome.

In the present situation where a semiconductor chip which is a smaller, lighter and thinner product is required as the integration density of integrated circuits is further improved, a lead frame which is a semi-finished product in the preceding stage is required. Also in the plating treatment of, the handling of the members is performed from the viewpoint that the frame substrate of the lead frame that is the processing target is thinned and easily curved or corrugated, and more controlled and uniform plating treatment is required. The conditions are becoming more severe. Also, in the plating process, the endless belt grips the part that is not needed in the final product, the semiconductor chip, so it will be cut and removed.
For this reason, there is a great demand to reduce the size of the portion as much as possible to effectively use the resources and reduce the cost, and from this point, the problem of improving the accuracy control of the transfer apparatus is extremely important. There is a big one.

Further, recently, the consistency and continuity of the production line have been emphasized, and the pretreatment process such as deburring performed before the plating process of the lead frame is continuously performed from the pretreatment process to the plating process. When planning equipment that can feed frames, use lead frames with unstable positions and postures, such as those conveyed by a conveyor, instead of the lead frames stored in magazine racks, as endless belts for plating equipment. A transfer device is required so that a desired posture and a reliable suspension are always performed. For this purpose, a new transfer device having a new configuration different from the conventional type is required.

The present invention has been made on the premise of the above-mentioned conventional techniques and the present situation, and its purpose is to process and manufacture products for which extremely strict product control is required, especially in the field of semiconductors. apparatus required in the process, specifically, when configuring the device for plating the strip-shaped member represented by the lead frame, exactly the endless belt, with a reliably suspended can move NoSo location and to provide a main Tsu key device.

Another object of the present invention is suitable for providing not only the demands of the conventional type apparatus but also the products of which the dimensional accuracy and the processing accuracy are more severe than ever. It is an object of the present invention to provide a strip-shaped member plating apparatus that can be used.

[0017]

Means for Solving the Problems In order to achieve the above-mentioned object, the inventor of the present invention has a strip-shaped member in a vertical posture or a slanted posture in which a pair of long sides or short sides thereof are vertically parallel to each other. While forming a bottomed groove type receiving cavity for loose fitting,
Receiving means for a strip-shaped member having a pair of opposing gripping members for gripping the upper portion in the thickness direction of the strip-shaped member loosely fitted in the receiving space, leaving an edge portion having a constant width as a gripping margin from the lower end thereof. When a reverse moving means Before moving to a predetermined transfer position in a state where the grip member gripping the strip-shaped member by a predetermined angle is projected upward the edges of the strip-like member from the grip member, A means configured to suspend the edge portion of the strip-shaped member moved to the delivery position by a belt that rotates endlessly, and a means for suspending the suspension means on the transfer side , and the pair of gripping members at the delivery position. Releasing means for releasing the grip of the strip-shaped member by the gripping member and returning the gripping member to the initial position forming the bottomed groove type receiving space, and rotation of the endlessly rotating belt. Gauge
The strip-shaped member suspended by the belt is immersed in the road.
Bell that comprises a kick bath and constitutes the suspending means on the transfer side
Are alternately elastically engaged with both sides of the edge of the strip member.
By rotating the narrow tongue that grips the strip member
The present invention has been completed, which is a strip-shaped member plating apparatus characterized in that it has comb teeth in a continuous direction .

In the above structure, the lead frame or the like is received in the bottomed groove type receiving space, and the received member is grasped by the grasping member and inverted. For this operation, even if the operation is relatively loose, it is allowed.On the other hand, the delivery of the received member to the next-stage device is the size and attitude of the grip margin for the lead frame of the next-stage device. This is because it is possible to give

Provision for configuring the plating apparatus of the present invention
In addition to the above-described structure, the transfer device is configured such that, in the bottomed groove type receiving cavity, the strip member loosely fitted in the receiving cavity moves from one side end to the other side end. It is also preferable to provide a gas spraying means for supplying the strip-shaped member and a positioning portion with which the other side end of the strip-shaped member engages. By doing so, the strip-shaped member such as the lead frame can be moved only in the vertical direction. Not only that, but also accurate positioning can be performed in the horizontal direction.

The present invention is typically applied to a lead frame plating apparatus, but the present invention is not particularly limited to this, and strip members are continuously transferred to a suspending means such as an endless belt. It can also be applied to other devices. When the present invention is applied to a plating apparatus for a lead frame, as a suspending means on the transfer side, a narrow width which grips the strip-shaped member by alternately elastically engaging both sides of the strip-shaped member is provided. It suffices to use an endless belt having tongue pieces continuously in the direction of rotation and having a comb-teeth shape, and to provide a plating bath in which the lead frame suspended by the belt is immersed on the rotation path of the endless belt.

[0021]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS The present invention will be described below in more detail as a case where the present invention is applied to an apparatus for plating the lead frame 1 shown in FIG.

An outline of the plating apparatus is as follows. The conductive endless belt 10 having the structure shown in FIG. 8 is rotated endlessly by four pulleys 40, 40, 40, 40 as shown in FIG.
On this rotation orbit, a loading unit 30 for suspending a lead frame on the endless belt by a transfer device described below, pretreatment for plating such as oxide film removal, plating, washing with water and drying after these treatments are sequentially performed. Plating processing part 3
1. Equipments such as an unloading unit 32 for removing the lead frame after the plating treatment from the endless belt, and a belt regeneration treatment unit 33 for removing the plating, washing, and drying the endless belt passing through the plating treatment unit are arranged. ing. Note that the specific configurations of the plating processing section 31, the unloading section 32, and the belt recycling processing section 33 are not directly related to the present invention. For example, the plating processing section uses known means such as a liquid flow-down type. Since it can be configured as follows, detailed description of the structure is omitted.

1 to 4 continuously show a series of movement states in an embodiment of the transfer apparatus of the present invention. In these figures, 50 is the loading shown in FIG. The frame main body of the transfer device disposed in the portion 30, the upper rising portion 51 is formed as a portion through which the endless belt 10 that intermittently moves in the track direction passes,
A pair of opening / closing operation claws 52, 52 for opening the tongue piece 11 of the passing endless belt to the left and right in the drawing and gripping the lead frame 1 are provided. These opening / closing operation claws 52, 5
In order to form a gap between the tip end engaging portions 12, the projection portion 13 of the tongue piece of the endless belt is pinched from the outside by means not shown when the intermittent movement of the endless belt is stopped. Which is similar to that described in FIG.

The frame main body 50 of this transfer device is equipped with a gripping device 60 constructed as follows. That is, the standing wall 62 is supported by the frame 61 provided so as to be movable in the vertical direction of the frame main body 50,
The reversing block 6 in which the shaft 63 is supported by the standing wall 62
8 is rotatably supported.

The reversing block 68 has a pair of plate-like gripping members (hereinafter referred to as "gripping plates") 64, which are arranged so as to be able to approach and separate from each other at their rotating tips.
65, and these gripping plates 64, 65 are shown in FIG.
In the initial position shown in FIG. 2, the bottom block 66 fixed to the pedestal 61 and a bottomed groove type receiving space 67 that opens upward are formed. Here, the bottom block 66 is made of an elastic material such as rubber, and prevents the lead frame 1 dropped and supplied from above from being deformed by a drop impact. In this example, the bottomed groove type receiving space 67 is shown as being formed vertically, but this is formed so that the pair of gripping plates are slanted to form the receiving space slanted for the purpose of mitigating drop impact. You may allow it. Further, the bottom block 66 is preferably provided with a smooth surface having a small friction coefficient for horizontal positioning described later.

The operation of the transfer device having the above structure will be described. As shown in FIG. 1, the pair of grip plates 64 and 65 are in a separated state, and a device having a space 67 is not shown. The lead frame 1 carried by means such as a transfer conveyor from the preceding apparatus is fitted into the space 67 from above by, for example, a drop method.

The lower end of the fitted lead frame 1 contacts the bottom block 66 of the space 67, and the lead frame 1 is vertically positioned.

Next, a pair of grip plates 64, 65 are operated to approach the lead frame in this state by a driving device such as a motor (or an air cylinder) not shown, and as shown in FIG. Hold one. At this time, the pair of grip plates 64 and 65 are spaced apart from the bottom block 66 in the upward direction by a predetermined length, so that the lower end of the lead frame projects from the lower end of the grip plate by the predetermined length. Incidentally, this protrusion length, transfected good to be able to adjust appropriately by adjusting the vertical position of the gripping plate and the bottom block.

Next, the reversal block 68 in which the lead frame is gripped by the pair of grip plates 64 and 65 is rotated by 180 ° as shown in FIG.
It is rotated by a degree so that the edge portion of the lead frame is projected upward from the pair of grip plates 64 and 65 by a predetermined length.
Then, the reversing block 68 in such a reversed state
To a delivery position set below the endless belt 10 by parallel drive means ( not shown ) (upward) .
4) , the front end engaging portion 12 of the endless belt in which the adjacent tongue pieces 11 are opened by the opening / closing operation claws 52, 52.
The edge is inserted between a and 12b. Then, the pressing of the opening / closing operation claws 52, 52 is released, and the lead frame is gripped and suspended by the comb-teeth-shaped tongue of the endless belt, and the delivery is completed.

A pair of gripping members 6 that have completed the above delivery
4,65 is spaced from each other to release the grip of the lead frame 1, the downward movement, the return rotation or the like of the inversion block 68 returns to its initial position shown in FIG. 1, ready for receiving the next read frame To be in a state.

By repeating the above operation, that is, the lead frame fitted in the receiving space is always positioned in an accurate position and posture by the bottom edge of the lead frame hitting the bottom block 68. An extremely accurate and stable transfer operation can be performed only by gripping (holding) 1 by a pair of grip plates, and reversing and moving (upper) the grip plates.

It is also preferable to adopt the configuration shown in FIG. 6 in order to realize more accurate transfer.

In this device, for example, a space 67 formed by the pair of grip plates 64 and 65 and the bottom block 68 described above.
In addition, the air blowing pipe 6 is provided on one side of the hollow in the horizontal direction.
9 is arranged, and a positioning portion 70 as a contact wall is provided on the other side. According to such a device, the lead frame is positioned not only in the vertical direction but also in the horizontal direction by being pressed against the positioning portion 70 by the action of the blowing air, so that the lead frame is always fixed by setting the stroke length of the intermittent feeding of the endless belt. Because of the positional relationship
There is an advantage that can make grip on the tongue of the end belt.

[0034]

According to the present invention, when a strip-shaped member typified by a lead frame is transferred so as to be grip-suspended by, for example, an endless belt of a plating device, the strip-shaped member is attached to the endless belt. Always accurately grasp the gripping margin,
Moreover, since the lead frame and the like can be accurately positioned at the delivery position, there is an effect that stable, accurate and reliable delivery can be performed. Further, in recent years, since the frame substrate of the lead frame is thinned, it tends to bend, and in general, this bending tends to cause an erroneous grip when gripping with the tongue of the endless belt. but in the case of applying the transfer apparatus of the present invention for transfer of the lead frame, said tabular grasping member Lee
And挾圧 the lead frame in the thickness direction correcting the curved tongue
In this state, the endless belt is inserted into the gap between the tongue pieces, so that there is an effect that the risk of erroneous grip is reduced.

Further, the delivery operation can be performed mechanically by a relatively easy principle that is not affected by the dimensions of the lead frame, processing tolerances, etc., and the dimensional accuracy and the processing accuracy are higher than ever. There is also an effect that an automated plating apparatus or the like can be provided at low cost even when providing a product that is strictly demanded.

[Brief description of drawings]

FIG. 1 is a plating apparatus according to an embodiment of the present invention, together with FIGS.
1 shows an outline of a transfer device used for mounting, and FIG. 1 shows a state in which a lead frame is loosely fitted in a bottomed groove type receiving space.

FIG. 2 shows a state in which a lead frame is held by a pair of holding members.

FIG. 3 shows a state in which the grip member is inverted.

FIG. 4 shows a state in which a gripping member moves to a delivery position defined below an endless belt to perform delivery.

FIG. 5 is a plan view showing an overall configuration outline of a plating apparatus to which the above transfer apparatus is applied.

FIG. 6 is a partially cutaway perspective view of a receiving space into which a lead frame is loosely fitted.

FIG. 7 is a schematic front view of a lead frame.

FIG. 8 is a perspective view for explaining the relationship between the structure of the endless belt of the plating apparatus and the lead frame suspended by the endless belt.

[Explanation of reference numerals] 1 ... Lead frame, 2 ... Semiconductor device, 3, 4 ... Edge portion, 10 ... Endless belt, 11a, 11b
... Tongue pieces, 12a, 12b ... Tip engaging portions, 13a, 13b
... Projection part, 30 ... Loading part, 31 ... Plating process part, 32 ... Unloading part, 33 ... Belt regeneration process part, 40 ... Pulley, 50 ... Frame body, 51 ... Upper rising part, 52 ... Opening / closing claw, 60 ... Gripping device, 61 ...
Frame, 62 ... Standing wall, 63 ... Shaft, 64, 65 ... Gripping plate, 6
6 ... Bottom block, 67 ... Receiving space, 68 ... Inversion block, 69 ... Air blowing pipe, 70 ... Positioning part.

 ─────────────────────────────────────────────────── ─── Continuation of the front page (72) Inventor David Weisberg United States Rhode Island 02910 Spectacle Street Cranston 1 Technique Incorporated (56) Reference JP-A-1-272798 (JP, A) JP-A-56-93899 ( JP, A)

Claims (3)

[Claims] 1. A strip-shaped member forms a bottomed groove type receiving cavity into which a pair of long sides or short sides are freely fitted in a vertical posture or an oblique posture in which they are vertically parallel, and the receiving cavity is formed. A strip-shaped member receiving means having a pair of opposed gripping members for gripping an upper portion of the strip-shaped member loosely fitted in the thickness direction from the lower end of the strip-shaped member while leaving an edge portion having a constant width as a grip margin; This gripping member gripping the member is rotated a predetermined angle
A reverse moving means Before moving to a predetermined transfer position in a state of projecting by rolling the edges of the strip-like member upwardly from grip member, the edge of the strip-shaped member which has been moved to the delivery position A means for suspending by a suspending means on the transfer side composed of an endlessly rotating belt, and releasing the grip of the strip-shaped member by the grip members by separating the pair of grip members at the transfer position, Returning means for returning the gripping member to the initial position forming the bottomed groove type receiving space , and the bell on the rotation track of the endlessly rotating belt.
Equipped with a plating bath in which strip-shaped members suspended in
The belt constituting the suspending means on the transfer side is
By alternately elastically engaging both sides of the edge of the strip member,
A narrow tongue that grips a strip member is continuous in the direction of rotation.
And a strip-shaped member plating device having a comb-like shape . 2. The receiving groove of bottomed groove type according to claim 1, wherein the strip-shaped member loosely fitted in the receiving groove moves from one side end to the other side end. A strip-shaped member plating apparatus comprising: a spraying means for applying a gas for applying a force; and a positioning portion with which the other side end of the strip-shaped member engages. 3. The strip-shaped member plating apparatus according to claim 1, wherein the strip-shaped member is a lead frame.