JPH01258926A - Apparatus for cutting cull - Google Patents

Abstract

PURPOSE:To accurately and surely split the boundary part between gate parts and molding articles by a process wherein a culls are fixed and all of the molding articles are held horizontally, furthermore, these molding articles are inclined and all of the gates are bent simultaneously. CONSTITUTION:A scooping paw 32 is raised and the whole lead frames L, L with cull are lifted up from a lower die, at the same time, a vacuum pump is activated and all of culls C are absorbed by means of a cull absorbing nozzle 63. The first lower surface pressing members 87, 87 are placed into contact with the lower surface of elements S at the central part of the lead frames L, L and the elements S are lightly held therebetween and upper surface pressing members 56, 56. Next, air-cylinders 49, 49 positioned at the upper part are activated and a receiving plate 46 is depressed. As a result, each crank plate 50 is opened, an upper inclining plate 53 is press-spread. Simultaneously, a pivoting plate 74 follows and pivots about a pin 74, so that the upper surface inclining plate 53 and each lower pressing member 85, 80 are inclined to the direction of separation from the cull C remaining packages S held therebetween. In this manner, the most thinned part can be split accurately.

Description

Detailed Description of the Invention "Field of Industrial Application" The present invention is directed to a cull cutting device that is used, for example, to automatically cut culls from each package after forming a resin package on a lead frame by transfer molding. Regarding.

``Prior Art'' As is well known, when forming a resin package on a wire-bonded lead frame, a transfer molding method that uses a low resin injection pressure is often used.

FIG. 10 and FIG. 11 are a plan view and a side view showing an example of a lead frame molded product obtained by this type of transfer molding, and the reference numerals in the figures indicate the lead frame, S
is a resin package (molded product), C is a cull that is the remainder of the resin during molding, and G is a gate portion that connects the cull C and the package S.

By the way, by cutting the gate portion G...
Conventionally, a thin disc-shaped roller is used to separate the parts. Then, after fixing this lead frame L with Cal C on a horizontal table, roll this roller while pressing it against the gate part G...
. . . will be pushed one after another.

"Problem to be Solved by the Invention" However, in the above cull cutting method, when pushing the gate part G... with a roller, the thinnest connecting part between the gate part G... and the package S... It does not necessarily mean that the gate part G... will break, and there may be inconveniences such as fragments of the gate part G... remaining on the package S... side, or the roller hitting the package S... and damaging the package S... There was a need for improvement.

"Means for Solving the Problems" The present invention has been made to solve the above problems, and includes a claw drive mechanism that includes a horizontal scooping claw and moves the scooping claw in the longitudinal direction and moves it up and down; A cull fixing means capable of fixing a cull connected to a molded product lifted by a mold, and an upper surface pressing member arranged to face the upper surface of the lifted molded product and capable of tilting, a movable body that is movable and operable to move; and a movable body that is movable up and down below another moving position of the movable body, and when the movable body is raised, a lower surface suppressor that can horizontally clamp a molded product between the upper surface presser and that is tiltable. The present invention is characterized by comprising: an elevating body having a body; and a tilting mechanism capable of tilting both the upper surface pressing body and the lower surface pressing body in a state in which the molded product is held between them.

"Function" In this cull cutting device, the movable body is first moved above the lower mold which is opened after molding, and then the scooping claw is moved up and down and opened/closed to scoop up the molded product with cull on the lower mold.

Then, with the cull connected to the molded product fixed by the cull fixing means, the movable body is moved to above the elevating body.

Next, the elevating body is raised to press the lower surface pressing member against the lower surface of the molded product, and then the scooping claw is removed from the molded product, and the molded product is further sandwiched and fixed between the lower surface pressing member and the upper surface pressing member.

In this state, the upper surface pressing member and the lower surface pressing member are tilted by the tilting mechanism to bend the gate portion between the cull fixed by the cull fixing means and the molded product. Thereby, with this device, it is possible to accurately and reliably break the narrowest connection part with the molded product among the gate parts.

Embodiment Hereinafter, a transfer molding apparatus employing an example of a lead frame transport mechanism (equipment) according to the present invention will be described with reference to the drawings.

First, an outline of the entire molding apparatus will be described using FIGS. 1 to 5. In addition, Fig. 1 is a front view of the device, Fig. 2 is a plan view, Fig. 3 is a right side view, and Figs. 4 and 5 are a right side view and a left side view with the cover attached. The front, rear, left, and right directions used in the description correspond to the state in which the device is viewed from the front.

Reference numeral 1 in the drawing denotes a magazine mounting table fixed on a base 2, on which a plurality of rectangular parallelepiped-shaped magazines M in which lead frames are stacked and housed are placed side by side at equal intervals. In addition, 3 lifts the magazines M one by one from the mounting table 1,
This is a magazine transfer mechanism that transfers the magazine onto the turntable 4.

The turntable 4 can place the magazine M eccentrically from the rotation axis, and by rotating the turntable 4 alternately forward and backward half a rotation, the magazine is alternately moved to the Pi or P2 position, and the frame is extruded. The mechanism 5 pushes out lead frames one by one from the magazine M at each position. The extruded lead frame is transferred into the transfer mold B by the frame transport mechanism 6 together with resin tablets sequentially supplied from the tablet supply mechanism 7. Reference numeral 9 denotes a cleaning mechanism that cleans the opposing surfaces of the upper and lower molds of the transfer mold 8.

Then, the lead frame L with a cull C formed in the transfer mold 8 as shown in FIGS. 10 and 11 is passed to the cull cutting mechanism 10, and the gate portion G... The lead frame L is separated from the cull C... and the package S... is formed in this way.
can be stored in a rack 12 by a product storage mechanism 11.

Next, the cull cutting mechanism (device) 10, which is the main part of the present invention, will be explained in detail using FIGS. 6 to 9.

At the rear of the transfer mold 8, as shown in FIG. 1, two guide bars 15 extending to the left and right ends of the device are arranged horizontally. are slidably attached at intervals, and both are connected by ball screws (not shown).
It is adapted to be moved along a guide bar 15.15.

A rectangular movable base plate (movable body) 18 is fixed to the upper ends of these supporting members 16 in a horizontal manner.

Above the four corners of the movable table plate 18, guide bars 19 extending in the front-rear direction are installed on the mounting members 20 and 2.
It is fixed horizontally via 1. In addition, between the guide bars 19 and 19 that form a pair in the left and right direction, there are posts 22, respectively.
An opening/closing support 23 is attached to the opening/closing support body 23 so as to be slidable back and forth.

As shown in FIG. 7, a pawl position adjustment screw 24 is rotatably attached to the lower surface of each opening/closing support 23 along the longitudinal direction, and an adjustment knob 25 is fixed to the center thereof. Furthermore, adjustment members 26 having female screw holes are screwed into the male threaded portions 24A formed on both sides of the pawl position adjustment screw 24, and when the adjustment knob 25 is turned, these adjustment members 26.26. are set to move at the same time. Further, a post 27 is fixed to the upper surface of each adjustment member 26, and the post 27 and the guide bar 28
An upper member 29 extending horizontally outward is attached so as to be movable up and down. Furthermore, a detent pin 30 is fixed to these upper members 29 and penetrates into the adjustment member 26 .

On the other hand, at the other end of each upper member 29, a lower end is provided with a movable base plate 18.
Claw support members 31 reaching downward are fixed, and thin scooping claws 32 are fixed horizontally to the lower ends of these claw support members 31 so as to face each other in the front-rear direction.

Furthermore, a middle plate 33 is horizontally hooked and fixed to the middle part of the claw support members 31, 31 arranged in the left-right direction. These intermediate plates 33 are supported so as to be movable up and down via a pair of guide bars 34, as shown in FIG. 7, with respect to the movable table plate 18.
It is biased downwardly through. Further, a claw lifting cylinder (claw drive mechanism) 37 is embedded and fixed upward in the upper surface of the movable base plate 18, facing the center of each intermediate plate 33, and when these claw lifting cylinders 370 rods are protruded,
The middle plate 33 is pushed up against the springs 36, and the scooping claws 32 are raised.

Furthermore, a pair of L-shaped plates 40, 40 facing each other are vertically fixed to the center of the movable base plate 18, and these L-shaped plates 40 are provided with a pair of claw opening/closing cylinders (claw driving cylinders) facing oppositely to each other. mechanism) 41 is attached. The ends of the rods of these claw opening/closing cylinders 41 are fixed to the opening/closing support 23 via connecting members 42, and the connecting length can be adjusted with screws 43.

On the other hand, support tubes 44 are vertically fixed to the upper surface of the central portion of the left and right ends of the movable table plate 18, respectively. These support tubes 4
4 includes a horizontal receiving plate 46 at the upper end via a post 45.
A rod 47 with a
It is usually raised upwards. In addition, when the movable base plate 18 is moved to the right end position, air cylinders (tilting mechanisms) 49 are disposed above these receiving plates 46 so as to face downward as shown in FIG. Fixed.

As shown in FIG. 9, a pair of crank plates 50 are connected to the lower ends of each of the rods 47 in an inverted V shape, and are rotatable in the front and rear directions. Further, one end of an actuating plate 51 is rotatably connected to the other end of these crank plates 50, and these actuating plates 51 can be operated in a state in which the rod 47 is raised (double-dashed line in FIG. It is adapted to be housed in a recess 52 formed on the lower surface of the movable table plate 18.

In addition, the front side actuating plates 51 and the rear side actuating plates 5
Upper tilting plates 53 extending in the left-right direction I are horizontally hooked and fixed between the two. A spring 54 is interposed between each of the upper tilting plates 53 and the movable base plate 18, and these springs 54 normally keep the upper tilting plate 53 in close contact with the lower surface of the movable base plate 18. There is. In addition, retaining bins 55 are fixed to both end surfaces in the longitudinal direction of each upper tilting plate 53 in a protruding state.

A thin upper pressing plate 56 is attached to the lower surface of each upper tilting plate 53. A pair of guide bars 57 are fixed upright at several locations on the upper surface of the upper pressing plates 56, and are penetrated by posts 58 fixed inside the upper tilting plate 53. Further, a spring 60 is attached to another part of the upper pressing plate 56 via a stopper rod 59 between the upper pressing plate 56 and the upper tilting plate 53, and the urging force of the spring 60 normally causes the upper pressing plate 56 to be kept at a constant distance from the upper tilting plate 53. They are kept parallel and spaced apart. In this state, the lower surface of the upper pressing plate 56 is located at a higher position than the upper surface of the scooping claws 32, which are in the lowered state.

As shown in FIGS. 7 and 8, the movable table plate 18 also has an elongated opening 61 formed along the center line in the left-right direction, and a nozzle fixing member 62 is inserted into the opening 61. , Cull C . . . , Cull suction nozzles (Cull fixing means) 63 . . . are installed in positions corresponding to Cull C . These cull suction nozzles 63 have nozzle openings that penetrate through the movable table plate 18 and open at approximately the same height as the lower surface of the upper pressing plate 56, and the upper part thereof is fixed to the nozzle fixing member 62 with a nut 65. Adjustable and fixed. All the suction nozzles 63 are connected to a vacuum pump via tubes (not shown).

On the other hand, below the position where the movable base plate 18 has moved to the right end,
As shown in FIG. 1, a lifting platform (
A lifting body) 70 is arranged horizontally, and a ball screw 71 provided upright on the side moves the movable table plate 18.
It is designed to be raised and lowered until it is close to the .

A side plate 7 is provided at the center of the right end and left end of this elevating table 70.
2.72 are fixed vertically, and on both sides of the upper end of these side plates 72, a pair of rotating plates 73 and 73 are respectively connected to the pins 7.
It is rotatably attached via 4. A notch 75 into which the engagement pin 55 of the upper tilting plate 53 is fitted is formed on the inner surface of the center portion of the upper end of the rotating plates 73 .

Furthermore, lower tilting plates 76 are fixed to the lower ends of the rotating plates 73 facing each other in the left and right direction, and these lower tilting plates 76 are interposed between the elevator platform 70. It is normally kept horizontal by a spring 77 (see Figure 8).

On the other hand, a pair of width position regulating members 78 is attached to the outer end of each lower tilting plate 76 so as to be movable along the guide protrusion 78B, and the bolts 78A are attached at positions corresponding to the width of the lead frame L. ... is fixed (see Figure 8). Moreover, longitudinal position regulating members 79° 79 for positioning both ends of the lead frame L are fixed to both longitudinal ends of each lower tilting plate 76 so as to be adjustable in position (see FIG. 7).

Furthermore, the upper surface pressing plate 5 is provided on the upper surface of each lower tilting plate 76.
6, a rectangular parallelepiped-shaped second lower surface pressing body 80 is movable up and down along a plurality of guide bars 81, and is supported by a spring 82.
It is mounted horizontally with an upward force (
(See Figure 8). The second lower pressing plate 80 has a rectangular opening 83 formed in its center. Furthermore, a width position regulating member 84.84, which faces the width position regulating member 78, 78, is fixed to the inner end of the second lower surface pressing member 80 via a port 85 and a spring 86.

On the other hand, a rectangular parallelepiped-shaped first lower surface presser 87 is housed in the opening 83 of the second lower surface presser 80 so as to be retractable. A guide bar 88 that vertically passes through the lower tilting plate 76 is fixed to the lower surface of the first lower pressing member 87, and is urged upward by a spring 89 so as to protrude from the second lower pressing member 8o. is maintained.

Next, the operation of the cull cutting mechanism 10 having the above configuration will be explained.

Now, use transfer mold 8 to make lead frame L.

After molding the package S into L, the mold 8 is opened.

Next, with the scooping claws 32... closed, the movable base plate 18
is moved along the guide bar 15.15 to the vicinity of the upper surface of the lower mold 8A, and the claw opening/closing cylinders 41, 41 are operated to open the scooping claws 32... and mold lifting cylinder 37.3
7, the lead frames L and L placed on the lower mold 8A
The scooping claws 32... are lowered on both sides of the scooping claws 32...
... and insert them into the gap between the lead frame L and the package S of L. Next, scooping claw 32...
・Raise the lead frame L, L with Cal C...
At the same time as lifting the whole thing from the lower mold 8A, the vacuum pump is activated and all the Cal C.
... adsorbs. The reason for adsorbing Cal C... in this way is that the gate part G
This is to prevent the gate surface of the product from becoming dirty due to breakage.

Next, the movable table plate 18 is moved to the original position I, and the elevating table 7
Position it directly above 0. Then, the lifting table 70 that was waiting below is raised by the ball screw 71, and the first lower surface suppressor 87.87 is brought into contact with the lower surface of the lead frame L, the element S in the center of the L, and the upper surface Pressing body 56.56
Lightly sandwich the element S between them. And scooping claw 32
After opening and pulling out the lead frames L and L from the lower surface, the lifting platform 70 is raised another step, the spring 89 supporting the first lower surface pressing body 87°87 is compressed, and the first 2 lower surface suppressors 80 and 80 are pressed against the lower surfaces of the remaining elements S... In this process, both the longitudinal and widthwise ends of the lead frames L, L are accurately positioned by the position regulating members 7g, 79.84. Moreover, the engagement pin 55 of the upper tilting plate 53.53...
However, the rotating plate 73 fixed to the lower tilting plate 76, 76...
into the notches 75..., and these are fixed relatively.

Next, operate the air cylinder 49.49 located above,
The receiving plates 46, 46 are simultaneously pushed down against the springs 48, 48. Then, each crank plate 50.50 connected to the lower end of the rod 47 opens as shown in FIG.
is pushed open.

At the same time, the rotating plates 73.73 engaged with the retaining pins 55.55 of each upper tilting plate 53 follow and rotate around the pins 74. Therefore, the upper surface pressing plate 56° 56 and each lower surface pressing member 85, 85, 80, 80 tilt in the direction away from the cull C, with the package S sandwiched between them. Package S... and Cal C.
Stress is concentrated at the smallest part of the gate G that connects the gates G, and these parts are torn apart at exactly the same time.

After completing the cull cutting in this way, use the air cylinder 49.4.
Return the rod No. 9, and each tilting plate 53, 53, 76, 7
Return 6 to horizontal position. Then, when the lifting platform 70 is lowered, the lead frame L is lowered in an inclined state with one end in the width direction placed on the first lower pressing plate 85 and the other end placed on the width position regulating member 78.78. . Then, the product storage mechanism 11 provided below picks up the two lead frames L, turns them in opposite directions, and stores them in the rack 12. It is configured to do this. On the other hand, the suction nozzle 63...
Cal C... is attracted to nozzle 63...
- A chute (path shown) is automatically inserted under the chute, the vacuum pump is stopped, and Cal C... is dropped onto the chute to be discarded, and one cycle is thus completed.

According to the cull cutting device having the above configuration, the cull C...
At the same time as suctioning and fixing all the packages S... horizontally, these packages S... are tilted in a direction perpendicular to the cull row to fix all the gate parts G...
Since the gate parts G... are bent at the same time, stress can be concentrated on the thinnest part of the gate part G, that is, the boundary with the package S, and this boundary can be broken accurately and reliably.

Therefore, compared to the conventional method in which the gate portion G... is successively broken with a P-ra, fragments of the gate portion G... may remain in the package S... or the package S... may be damaged. This eliminates the risk of spoiling the aesthetic appearance of the package S.

Additionally, in this device, even if the size of the lead frame L is changed, adjustment mechanisms are provided in each part.
By adjusting these, it has the advantage of being able to accommodate lead frames of any size.

In the above embodiment, a case was described in which the lead frame L is a lead frame with culls arranged in two rows on both sides of the cull C, but the above device can be used without changing the configuration.
The gate cutting process can also be performed when the lead frame has only one row on one side. Furthermore, by expanding the configuration of the above-mentioned apparatus, it is possible to process molded products in which three or more lead frames are connected by culls.

Further, the cull fixing means is not limited to the suction method, but may also be a structure in which the cull is clamped with claws. Furthermore, it is also possible to apply the present invention to transfer molded products other than element packages.

"Effects of the Invention" As explained above, according to the cull cutting device of the present invention,
In addition to fixing the cull, all the molded products are held horizontally, and the molded products are tilted to bend all the gate parts at the same time. Stress is concentrated and this boundary can be broken accurately and reliably.

Therefore, compared to the conventional method in which the gate parts are successively broken using a row arm, fragments of the gate part remain on the molded product and the molded product is not damaged by the rollers, eliminating the risk of damaging the aesthetics of the molded product. can.

[Brief explanation of the drawing]

1 to 5 show the overall outline of a transfer molding apparatus employing an example of the lead frame conveyance mechanism according to the present invention, in which FIG. 1 is a front view, FIG. 2 is a plan view, and FIG.
The figure is a right side view, and FIGS. 4 and 5 are a right side view and a left side view with the cover attached. 6 to 9 show the cull cutting mechanism which is the main part of the present invention, FIG. 6 is a plan view, FIG. 7 is a front view,
FIG. 8 is a side sectional view, and FIG. 9 is a side view. Furthermore, FIGS. 10 and 11 are a plan view and a side view showing an example of a lead frame with a cull. L...Lead frame, S...Element package, C
...Cal, G...Gate part, 10...
- Cull cutting mechanism, 18... Moving base plate, 32... Scooping claw, 37... Claw lifting cylinder (claw drive mechanism), 41...
Claw opening/closing cylinder (claw drive mechanism), 49...Air cylinder (main part of tilting mechanism), 56...Top pressure plate, 63...Cal suction nozzle (fixing means), 70... Lifting platform ( elevating body), 80... second lower surface pressing body, 87... first lower surface pressing body.

Claims (1)

[Scope of Claims] A claw drive mechanism comprising a horizontal scooping claw and moving and raising and lowering the scooping claw in the longitudinal direction; and a cull fixing means capable of fixing the cull connected to the molded product lifted by the scooping claw. ,
a movable body that is operable to move above the lower die of the mold, the movable body comprising an upper surface pressing body that is arranged to face the upper surface of the lifted molded product and is tiltable; and a lower part of the other moving position of the movable body. an elevating body provided with a lower pressing body that is movable up and down and capable of horizontally clamping and tilting a molded product between the upper pressing body and the upper pressing body when the lifting body is raised; and a tilting mechanism capable of tilting both the lower surface pressing body.