JP2852171B2 - Lead cutting machine - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a lead cutting machine,
In particular, the present invention relates to a lead cutting machine used for cutting outer leads and individual lead frame frames in a semiconductor device manufacturing process.

[0002]

2. Description of the Related Art A lead cutting machine having a schematic configuration shown in FIG. 7 is used to perform an external lead cutting process shown in FIG. Other than the external lead cutting section 36 that actually performs the external lead cutting process in the schematic configuration shown in FIG. 7, the automatic setting according to the type of the semiconductor device can be easily performed by the related art, and thus the description is omitted.

The conventional external lead cutting section uses a lead cutting die 21 shown in FIG. 5, and the equipment has a press unit 22 for pressing the lead cutting die 21.

Next, the operation of cutting the external lead 17 into the shape shown in FIG. 4B will be described with reference to FIG. The lead frame 1 after mold sealing is placed on the cutting die 4 fixed to the lower base plate 23. The upper base plate 26 connected to the press unit 22 shown in FIG.
Collides with the lead frame 1 and is pinched between the cutting die 4. If the upper base plate 26 continues to descend even after the collision,
The cutting punch 3 incorporated in the punch insert 28 and fixed to the upper base plate 26 is a stripper plate 29
The lead frame 1 is further protruded and inserted into the die cutting groove 30 of the cutting die 4 to cut the lead frame 1. At this time, the cutting range is as shown in FIG.
The cutting punch cutting length dimension 32 and the cutting punch cutting width dimension 33 shown in (c) are in the range, and are determined by the component dimensions of the cutting punch 4 and cannot be changed.

[0005]

In this conventional lead cutting section, the cutting punch incorporated in the upper base plate is moved vertically up and down by the vertical movement of the upper base plate using the press unit as a drive source, and the die cutting of the cutting die is performed. An external lead is cut by inserting a cutting punch into the groove. Therefore, the cutting dimension when cutting the lead frame is one type in one lead cutting die, and only a semiconductor device having a common cutting dimension can be shared. If the cutting dimensions are different, the cutting die is replaced. Was compatible. For this reason, the number of mold changing steps is increasing while the production of many kinds and small quantities is progressing. In addition, each time a new model was supported, a cutting die was designed, manufactured and obtained. Therefore, it took time and cost to design and manufacture the cutting die, and quick response was impossible. At present, as semiconductor devices are becoming denser and more compatible with ASICs, it is expected that the development of new models will be increasingly spurred, and there is a situation where more rapid response is required.

On the other hand, in terms of the maintenance and management of the mold, a spare part of the cutting blade, which wears along with the cutting, is required. Therefore, the number of spare parts is increasing as the number of types of the cutting mold increases. Further, since the conventional lead cutting die for a semiconductor device has a structure in which one external lead of one semiconductor device or a plurality of semiconductor devices is cut by one vertical up and down movement, a large pressure of 1 to 5 Ton is applied. However, there is a problem that noise and vibration are large.

[0007]

A lead cutting machine according to the present invention mounts and fixes a lead frame on a cutting die fixed to a base plate. The cutting punch attached to the disk is a part of the circumference on a circle concentric with the disk, and is incorporated so that it can rotate on the disk support plate via a radial bearing around the rotation axis. Is connected via a coupling to a disk rotation motor of a rotary drive source attached to the disk support block. Furthermore, the disk support plate is attached to the base plate via an LM guide, and the motor for the disk slide mounted on the base plate is used as a drive source, and the rotation operation is changed to the slide operation via the ball screw and the ball screw bush mounted on the disk support plate. Converting. The slide operation is performed in parallel with the die cutting groove of the cutting die, and the disk is simultaneously rotated and slid, whereby the cutting punch is inserted into the die cutting groove to cut the lead frame. The cutting range of the external lead is limited to the external lead cutting portion. Select one to apply from among several types of cutting punches attached to the disk. The rotation and slide operation of the cutting punch can be set arbitrarily by a disk rotation motor and a disk slide motor, and the cutting punch can be inserted at any position in the direction parallel to the die cutting groove. Can be cut according to each semiconductor device.

[0008]

DESCRIPTION OF THE PREFERRED EMBODIMENTS Next, the present invention will be described with reference to the drawings.

FIG. 1 is a view showing a semiconductor device cutting machine according to a first embodiment of the present invention. FIG. 1 (a) is a sectional view and FIG. 1 (b) is a sectional side view.

In this embodiment, a cutting die 103 having a cutting groove 120 having a fixed width fixed on a base plate 101, and a disk-shaped punch moving a predetermined height on the cutting die 103 in parallel with the cutting groove 120 are provided. 109a, and a stripper plate 105 for inserting the lead frame 1 into the cutting die 103 is provided. The distance between the cutting die 103 and the disk-shaped punch 109a is maintained at a constant distance by the support 102 and the top plate 112, and the thrust bearing 111 attached to the top plate 112 is provided.
The disk-shaped punch 109a attached to the punch holding block 110 with the guide as the guide has a center radial bearing 108 provided for the disk-shaped punch 109a that moves in parallel with the cutting die 103, and can freely rotate in the punch holding block 110. It is kept as possible. Also, a disc-shaped punch 1
The horizontal movement 09a is performed by the driving cylinder 128.

Next, the operation will be described. When the cylinder 113 is driven and the stripper plate 105 is lowered via the cylinder connecting plate 114 and the connecting lot bar 106, the lead frame 1 riding on the cutting die 103 is inserted and fixed. In this state, the disk-shaped punch 109a slides in parallel with the cutting groove 120.
The lead frame 1 includes a disc-shaped punch 109a and a cutting die 1.
03 with the cutting groove 120, and a shear load is applied.
Cut at zero width. According to the present embodiment, cutting can be performed with a pressure of about 5 kg, which is the thrust of the driving cylinder 128.

FIG. 2 shows a second embodiment of the present invention. FIG.
13A, the disc-shaped punch 209a and the shaft pin 207
Is locked with a key 227, and the shaft pin 207 is fixed to the punch holding block 210 via a radial bearing 208. A gear 226 is provided at the right end of the shaft pin 207,
Similarly, the key 227 is used to stop rotation. The rack 225 is fixed to the die base plate 232. The die base plate 232 is slid horizontally by the driving cylinder 233 together with the cutting die 203 fixed thereon.
The lead frame 1 is fixed on the cutting die 203 by a cylinder (fixing means is not shown). FIG. 2 (b)
Notch at the tip of the blade of the disc-shaped punch 209a.
30 are provided. The notch 230 is provided in order to leave an uncut portion on the lead frame.

According to the present embodiment, since the rotation angle of the disk-shaped punch 209a can be controlled by the sliding amount of the gear 226, the cutting range (cut length 2)
There is an advantage that it is possible to set 31). Also, by setting the gear 226 to an arbitrary number of teeth, the gear 22
The cutting range can be changed for the rotation angle of 6.

Next, the configuration and operation of a third embodiment of the present invention will be described below with reference to the front view of FIG. 3A and the sectional side view of FIG. The present embodiment is particularly characterized by the shape of the cutting punch. As shown in FIG. 3B, the cutting punch 303 is a part of the concentric circumference of the disk 302 about the rotation shaft 306 as the center of rotation. One end of the rotating shaft 306 is connected via a coupling 307 to a rotating shaft of a disk rotating motor 308 attached to the disk supporting plate 309. The rotating shaft 306 is fixed to the disk support plate 309 via the radial bearing 305. Further, the disk support plate 309 is attached to the base plate 312 via the LM guide 310, and the base plate 31
The rotation axis of the disk slide motor 313 attached to 2 is connected to a ball screw 314, and the rotational movement is converted to slide movement via a ball screw bush 311 attached to the disk support plate 309.

The cutting die 304 is connected to the base plate 31.
2 is fixed to a position where the cutting punch 303 can be inserted into the die cutting groove 330. Here, the shape and mechanism of the cutting punch, which is a main part of the present embodiment, will be described in detail.
The cutting punch 303 has a cutting length dimension 332 and a cutting punch cutting width dimension 333 specified by the product drawing, and the cutting punch 303 mounted on the disk 302 is designated by the product drawing. A cutting punch 303 having an appropriate size is selected. Cutting punch 303
Is selected using the disk rotation motor 308. The selected cutting punch 303 is connected to the disk rotating motor 30.
In response to the drive of the disk slide motor 8 and the disk slide motor 313, it is inserted into the die cutting groove 330 of the cutting die 304 while simultaneously performing rotation and sliding operation.

Next, the mechanism of the cutting operation of this embodiment will be described below. Prior to the lead cutting process, the cutting punch 303 is selected by inputting the identification code of the object to be cut, and the process ends. When the lead frame 1 is fixed on the cutting die 304 in this state, the disk slide motor 313 starts driving, and the cutting punch 303 starts sliding. At the same time, the disk rotating motor 308 starts driving, and the cutting punch 303 starts rotating around the rotating shaft 306. When the operation is started, the cutting punch 303 is inserted into the die cutting groove 330 little by little, and one side of the external lead 17 arranged in four directions is cut little by little. The rotation stops. The width of the die cutting groove 330 is
The size is determined by adding 12% to 20% of the thickness of the workpiece to the cutting width 333 of the cutting punch specified in the product drawing. When inserting the punch 303 into the die cutting groove 330, 6% to 1% on one side.
Set so that a 0% gap can be secured. Since this is a conventionally well-known shearing process, a description thereof is omitted here. The insertion depth of the cutting punch 303 into the die cutting groove 330 is always constant because the cutting punch 303 is a part of the circumference around the rotation shaft 306. Also, cutting punch 3
No. 03 is inserted into the die cutting groove 330 while performing a rotating operation and a sliding operation, but the cutting length is arbitrarily operated while the ratio of the rotating operation speed of the tip to the sliding operation speed of the tip of the cutting punch 303 is up and down 10%. It was confirmed that it was possible and did not affect the product quality of the semiconductor device.

Next, a fourth embodiment of the present invention will be described with reference to a plan view of FIG. 8A and a front view of FIG. Third
The structure shown in the embodiment is fixed to each of two sets of slide tables 442, and is fixed to the base plate 12 via the LM guide 410. The slide table 42 has a right-hand thread on one side and a left-hand thread on the other, and has a ball screw 414 inserted therein so as to mesh with the right-hand and left-hand threads, and is fixed to the base plate 412.
1 is a driving source and is connected to a rotating shaft. Therefore, the cutting position can be arbitrarily set by the disk spacing motor 441.

[0018]

As described above, according to the present invention, the external lead cutting of a semiconductor device having different cutting dimensions can be performed by setting an external lead cutting portion capable of setting an arbitrary cutting dimension and a data storage device necessary for processing a workpiece. Has eliminated the problem of mold replacement work, which has been a problem in the past, by means of an automatic data retrieval device based on the code of the workpiece. In addition, mold design and production costs for the development of new models are unnecessary, enabling quick production response.
This has the effect of eliminating the need to store a large number of cutting blade spare parts.

On the other hand, since no press unit is used, noise and vibration are less generated.

[Brief description of the drawings]

FIG. 1 is a diagram showing a first embodiment of the present invention, and FIG.
Is a front sectional view, and FIG. 4B is a side sectional view.

FIG. 2 is a view showing a second embodiment of the present invention, wherein FIG.
Is a front sectional view, and FIG. 4B is a side sectional view.

3A and 3B show a third embodiment of the present invention, wherein FIG. 3A is a front view, and FIG. 3B is a right side vertical view.

FIG. 4 (a) is a view of a workpiece before processing and FIG.
Indicates after processing.

FIG. 5 is a diagram showing a conventional external lead cutting section.

6 (a) is a longitudinal sectional view, FIG. 6 (b) is a plan view of a lower side, and FIG. 6 (c) is a view of an upper side of a lead cutting die mounted on a conventional external lead cutting portion. FIG.

FIG. 7 is a schematic plan view of a conventionally operated lead cutting machine.

8 (a) is a plan view, FIG. 8 (b) is a front view, and FIG. 8 (c) is a cut-away side view of a fourth embodiment of the present invention.

[Explanation of symbols]

 REFERENCE SIGNS LIST 1 lead frame 17 external lead 18 PKG 19 frame-cut lead frame 20 external lead cutting part 21 lead cutting die 22 press unit 23 lower base plate 24 guide post 25 guide bush 26 upper base plate 27 hanger 28 punch insert 29 stripper plate Reference Signs List 30 die cutting groove 31 upper base plate operation direction 32 cutting punch cutting length dimension 33 cutting punch cutting width dimension 34 semiconductor device input section 35 frame-shaped semiconductor device transport section 36 external lead cutting section 37 frame piece cutting section 38 frame piece cutting section 38 frame piece piece Semiconductor device transport section 39 Semiconductor device recovery section 40 Semiconductor device transport direction 101 Base plate 102 Post 103, 203 Cutting die 105 Stripper plate 106 Connecting lot rod 107, 207 Axis pin 108, 208 Al bearings 109, 209 Cutting punches 109a, 209a Disc-shaped punches 110, 210 Punch holding blocks 111 Thrust bearings 112 Top plates 113 Stripper drive cylinders 114 Cylinder connecting plates 225 Racks 226 Gears 227 Keys 230 Notches 231 Cutting lengths 302 Disks 303 Cutting punch 304 Cutting die 305 Radial bearing 306 Rotating shaft 307 Coupling 308,408 Disk rotation motor 309 Disk support plate 310,410 LM guide 311 Ball screw bush 312,412 Base plate 313,413 Motor for disk slide 314,414 Ball screw 315 Disc rotation direction 316 Disc sliding direction 441 Disc spacing motor 442 Slide table

Claims (1)

(57) [Claims] 1. In a semiconductor device manufacturing process, in cutting an outer lead and cutting a lead frame frame piece after resin sealing, several blades each having a shape in which a circumferential portion of a disk is cut out, and widths of the blades. A storage device that has a cutting die having the same groove, and further uses a mechanism that independently performs the rotating operation and the sliding operation of the blade, and stores information such as the cutting dimensions and shape of the object to be cut, and identification of the object to be cut. A lead cutting machine characterized in that an appropriate tool is selected by a device for inputting a code to obtain an arbitrary cutting size, shape and the like.