JP3123269B2 - Lead frame transfer device - 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 frame transfer device for picking up lead frames which are stacked and stocked one by one with a chuck claw and transferring them to a predetermined position.

[0002]

2. Description of the Related Art After plating a lead frame,
An inspection is performed to determine whether the plating has been properly formed. Such plating inspection is performed by picking up the solidly stacked lead frames one by one by a transfer device and transferring the lead frame to an inspection stage.

FIG. 9 shows a conventional lead frame transfer device, in which 1 is a first chuck claw, 2 is a second chuck claw, and the chuck portions 3, 4 are respectively formed in a C-shape. Is provided. The surfaces of the chuck portions 3 and 4 are
The lead frames 5 are both rough surfaces so that the lead frames 5 can be easily chucked.
Are picked up one by one and picked up and transferred to a predetermined position.

[0004]

However, the above-described conventional lead frame transfer apparatus has problems that the lead frame 5 cannot be satisfactorily chucked and is dropped, or two or more lead frames 5 are easily picked up at the same time. There was a point. Such a lead frame transfer device is used not only in the plating inspection process but also in the case of transferring a lead frame solidly stacked on a stocker to a predetermined position in a die bonder or the like. There was a point.

SUMMARY OF THE INVENTION It is therefore an object of the present invention to provide a lead frame transfer apparatus capable of reliably picking up solid lead frames one by one and transferring them to a predetermined position.

[0006]

SUMMARY OF THE INVENTION Accordingly, the present invention provides a method for picking up a lead frame by chucking a lead frame from right and left by a first chuck jaw and a second chuck jaw.
Up and down moving means for relatively vertically moving the chuck pawl and the second chuck pawl.

[0007]

According to the above construction, when the lead frame is chucked and picked up by the first chuck jaws and the second chuck jaws, the first chuck jaws and the second chuck jaws are relatively moved up and down. This makes it possible to reliably pick up one lead frame.

[0008]

Next, an embodiment of the present invention will be described with reference to the drawings.

FIG. 1 is an overall perspective view of a lead frame transfer device. Reference numeral 11 denotes a base, on which a plurality of poles 12 are erected in the center of the upper surface, and a large number of lead frames 5 are stacked and stocked inside the poles 12. On the side of this frame 12 is a second pole 1
3 are provided upright. The lead frame 5 from which a pickup error has occurred is collected inside the pole 13. That is, these poles 12 and 13 are stockers for the lead frame 5. Numeral 60 denotes a magnetic sensor provided on the side of the pole 12, which detects the number of lead frames 5 picked up by means described later.

At the rear of the base 11, a support 14 is provided upright. A horizontally long moving table 15 is supported on the upper front surface of the column 14. Reference numeral 16 denotes a motor for driving the moving table 15. On the front surface of the moving table 15, a bracket 17 having an L-shaped cross section is provided. A cylinder 21 as an elevating means is provided on the upper surface of the bracket 17.
Is provided. When the motor 16 is driven as described later, the first chuck claw 3 held on the bracket 17 is moved.
9 and the second chuck pawl 47 move horizontally in the Y direction.

In FIG. 2, a rod 22 of a cylinder 21
Is connected to a frame 23 having an inverted U-shaped cross section. Therefore, when the cylinder 21 is driven to project the rod 22, the frame 23 is lowered, and when the rod 22 is retracted, the frame 23 is raised. Reference numeral 18 denotes a vertical guide rod for guiding the frame 23 up and down.

In FIG. 2, a horizontal ball screw 24 is provided inside a frame 23, and a motor 25 for rotating the ball screw 24 is mounted on a side surface of the frame 23. A left screw 26 is formed on the left side of the ball screw 24, and a first nut 27 is screwed into the left screw 26. On the right side of the ball screw 24, a right-hand thread 28 is formed.
Nut 29 is screwed.

A bracket 31 having an inverted U-shaped cross section is connected to the lower surface of the first nut 27, and a pulse motor 32 is disposed inside the bracket 31. The rotary shaft 33 of the pulse motor 32 extends downward, and a lower-end portion thereof is connected to a cam 34 having a different shape. A vertical Z rail 35 is mounted on the side surface of the bracket 31. A slider 36 is fitted on the Z rail 35, and a frame 37 is mounted on the slider 36.

A holder 38 is mounted on a lower portion of the inner surface of the frame 37. A first chuck claw 39 is rotatably mounted on a lower portion of the holder 38 around a pin 40.
A horizontal shaft 41 extends from the rear surface of the frame 37, and a cam follower 42 that is in contact with a cam surface 34 a formed on the lower surface of the cam 34 is axially mounted at the tip of the shaft 41. 43 is a bracket 31 and a frame 37
The cam follower 42 attached to the frame 37 via the pin 40 is brought into contact with the cam surface 34 a of the cam 34 by the spring force of the coil spring. Accordingly, when the pulse motor 32 is driven to rotate the cam 34 horizontally, the slider 36 slides along the Z rail 35, and the first chuck 39 moves up and down. That is, the pulse motor 32, the cam 34, the cam follower 42, and the like constitute vertical moving means for vertically moving the first chuck pawl 39 with respect to the second chuck pawl 47 (described later).
A coil spring 44 is stretched between the holder 38 and the first chuck claw 39. The first chuck pawl 39 is resiliently rotated so as to rotate inward (counterclockwise) by the spring force of the coil spring 44, but its rotation limit is defined by hitting the stopper 50. As described later, when the first chuck claws 39 press against the side surface of the lead frame 5 to chuck the lead frame 5, the first chuck claws 39 are moved outward (clockwise) against the spring force of the coil spring 44. Direction) slightly. That is, this coil spring 44
Is for imparting a cushion effect to the first chuck claw 39.

In FIG. 2, a frame 45 having an inverted L-shaped cross section is mounted on the lower surface of the second nut 29. A holder 46 is mounted on a lower inner surface of the frame 45, and a second chuck pawl 47 is mounted on a lower portion of the holder 46. A slider 48 is provided on each of the upper surfaces of the bracket 31 and the frame 45. The slider 48 is provided on a horizontal Y-axis provided on the ceiling surface of the frame 23.
It is fitted on the rail 49. Therefore, when the motor 25 is driven to rotate the ball screw 24, the nuts 27, 29
Chuck jaws 39 and second chuck jaws 47 integrated with
Move horizontally in opposite directions.

Here, when the motor 25 rotates forward, the first
Chuck jaws 39 and the second chuck jaws 47 approach each other and chuck the lead frame 5 from the left and right. When the motor 25 rotates in the opposite direction, the first chuck pawl 39
And the second chuck pawl 47 are separated from each other to release the chuck state. Therefore, the ball screw 24, the motor 25, and the nuts 27 and 29 constitute opening / closing means for opening and closing the first chuck jaws 39 and the second chuck jaws 47. FIG. 3 shows the arrangement structure inside the frame 23. The frame 37 and the frame 45 have a first chuck claw 39 and a second chuck claw 39, respectively.
Of the lead frame 5 are chucked by the four chuck claws 39 and 47.

In FIG. 2, a chuck portion 51 is mounted on the lower inner surface of the first chuck claw 39. The front surface of the chuck portion 51 has a smooth surface so that the lead frame 5 can slide easily. FIG. 4 is a partially enlarged view of the chuck portion 51, and an edge E1 is formed on the front surface thereof. This edge E1 is
2 is formed by cutting
A hole 53 is formed at the back of the hole. When the lead frame 5 is chucked, the edge E1 is pressed against the side surface of the lead frame 5 as shown. Lead frame 5
The burrs 54 at the time of molding are adhered to the end face of the. If the burrs 54 adhere to the edge E1 in a large amount, a malfunction occurs in the chuck operation. Therefore, by forming a slit 52 and a hole 53 in the chuck 51, the burrs 54 are accumulated inside the hole 53 through the slit 52, thereby eliminating chuck errors.

A chuck portion 56 is also provided at the lower portion of the front surface of the second chuck claw 47. This chuck portion 56
Has a rough surface with a large coefficient of friction to prevent the lead frame 5 from slipping. This roughened surface is formed by roughening the surface of the chuck portion 56 made of stainless steel,
Alternatively, it is ensured by forming the chuck portion 56 from a material having a large friction coefficient such as hard rubber. As shown in FIG. 2, the chuck portion 51 and the chuck portion 56 are disposed so as to face each other in a C shape.

In FIG. 1, a transport rail 57 is provided between the poles 12 and 13. The transport rail 57 transports the lead frame 5 chucked and transported by the chuck claws 39 and 47 to the next step such as a plating inspection device or a die bonder (not shown). 58
Is a frame for supporting the transport rail 57.

FIG. 5 is a block diagram of an electric circuit. 61
Denotes a control unit such as a CPU, 62 denotes a memory, 63 denotes an input unit such as a keyboard, and 64 denotes a driver. Control unit 61
Controls the motors 16, 25, 32 via a driver 64 and controls the cylinder 21. The memory 62
Required data such as dimensions of the lead frame 5 is registered in the.

This lead frame transfer device is constructed as described above. Next, the overall operation will be described with reference to FIGS.

First, in FIG. 1, the motor 16 is driven to move the bracket 17 in the Y direction so that the first
Of the chuck jaws 39 and the second chuck jaws 47 of the pole 12
Is located above the leadframe layer solidly stacked in the inside. FIG. 6A shows this state. Next, FIG.
As shown in FIG.
And the first and second chuck claws 39 and 47 are lowered.

Next, by rotating the motor 25 shown in FIG. 2 forward, the first chuck jaws 39 and the second chuck jaws 47 are brought close to each other, and as shown in FIG. The uppermost lead frame 5 is chucked. FIG. 7 shows the chuck operation of FIG. 6C in more detail. That is, as shown in FIG. 7A, the first chuck jaws 39 and the second chuck jaws 47 are lowered to the position sandwiching the uppermost lead frame 5, and then the first rotation is performed by the motor 25 rotating. The chuck jaws 39 and the second chuck jaws 47 approach each other, but in this case, first, as shown in FIG. As shown in the drawing, some of the lead frames 5 near the uppermost row stacked as shown are shifted to the left. By doing so, the lead frames 5 are separated from each other, and two or more lead frames 5 are not picked up.

Next, when the motor 25 further rotates, the uppermost lead frame 5 is brought into contact with the first chuck claws 39.
And the second chuck pawl 47 chucks from the left and right (see chain lines in FIGS. 6C and 7B). Next, by driving the pulse motor 32 shown in FIG. 2 to rotate the cam 34, the first chuck claw 39 is raised. When only the first chuck pawl 39 is raised in this manner, the first
The chuck claw 39 of FIG.
(C) The left edge E of the lead frame 5 up to the solid line position
3, the lead frame 5 is chucked at the edge E1 when the edge E1 hits the end face of the lead frame 5, and when the first chuck claw 39 still rises in this state, the lead frame 5 5 right edge E
2 is in contact with the chuck portion 56 which is a rough surface, so that the lead frame 5 is centered on the right end edge E2 in FIG.
Rotate clockwise from the solid line position (c) to the chain line position. In this case, the cam 34 may be rotated in the forward and reverse directions by reversing the forward rotation and the reverse rotation of the pulse motor 32, and the first chuck claw 39 may be moved up and down. The next lead frame 5, which tends to adhere to the lower surface of the upper lead frame 5, is sieved, so that only the uppermost lead frame 5 can be reliably picked up.

When the lead frame 5 is chucked by the chucks 51 and 56 in this manner,
The rod 22 of the cylinder 21 is retracted, and the chuck pawl 3
9 and 47 rise to complete the pickup of the lead frame 5 (see FIGS. 6E and 7D).

Next, the motor 32 is driven to drive the chuck pawl 3
9 and 47 are lowered to bring the picked-up lead frame 5 into a horizontal posture. Next, when the motor 16 shown in FIG. 1 is driven, the chuck claws 39 and 47 are horizontally moved above the transport rail 57, and the cylinder 21 is driven there to cause the rod 22 to protrude.
When the motor 25 reversely rotates, the first and second chuck jaws 39 and 47 move horizontally in a direction away from each other to release the chuck state.
The lead frame 5 is transferred onto the transport rail 57. Then, the transport rail 57 transports the lead frame 5 to the next step, and the motor 16 is driven in the reverse direction to
Of the chuck jaws 39 and the second chuck jaws 47 of the pole 12
Is returned to above the lead frame 5 solidly stacked therein, and the above operation is repeated. Note that two or more lead frames 5 are picked up by the first chuck claws 39 and the second chuck claws 47.
, The two or more lead frames 5 are collected inside the pole 13 as described above.

The dimensions of the lead frame 5 differ depending on the type. Then, referring to FIG.
The operation corresponding to the change of the type of the lead frame 5 will be described. FIG. 8A shows a state in which a lead frame 5A having a large width is being picked up. This pickup operation is as described with reference to FIGS. 6 and 7, but the lead frame 5A is inclined at the angle θ1 by driving the pulse motor 32 and raising the first chuck jaws 39. . At this time, the first chuck claws 39
The distance between the second chuck pawl 47 and the second chuck pawl 47 is L1, and the height difference is D1.

FIG. 8B shows a state in which a lead frame 5B having a small width is picked up by changing the type. In this case, the distance L2 between the first chuck pawl 39 and the second chuck pawl 47 must be reduced in accordance with the width of the lead frame 5B. It is performed by

The angle θ2 of the lead frame 5B must be the same or almost the same as the angle θ1, and if the angle θ2 is too large or too small, the lead frame 5B is likely to be erroneously picked up. Therefore, the height difference D2 between the first chuck claw 39 and the second chuck claw 47 must be smaller than the height difference D1. This is because if the height difference D2 is the same or almost the same as D1, the angle θ2 at which the lead frame 5B is inclined becomes extremely large, and it becomes difficult to chuck the first chuck jaws 39 and the second chuck jaws 47. Because it becomes. Therefore, the dimensions of the lead frame 5 are registered in the memory 62 shown in FIG. 5 in advance, and when the type of the lead frame 5 is changed, the motor 25 is adjusted so that, for example, L: D becomes constant. The controller 61 controls the rotation amount of the pulse motor 32 and the like. The present invention is not limited to the above embodiment. For example, in the above embodiment, only the first chuck pawl 39 is moved up and down by the pulse motor 32, but the second chuck pawl 47 may be moved up and down. In short, the first chuck jaws 39 and the second chuck jaws 47
Should be relatively moved up and down.

[0030]

As described above, according to the present invention, the solid lead frames can be reliably picked up one by one by the first and second chuck claws and transferred to a predetermined position. it can.

[Brief description of the drawings]

FIG. 1 is a perspective view of a lead frame transfer device according to an embodiment of the present invention.

FIG. 2 is a front view of a main part of a lead frame transfer device according to an embodiment of the present invention.

FIG. 3 is a bottom view of a main part of the lead frame transfer device according to one embodiment of the present invention.

FIG. 4 is a partially enlarged view of a chuck portion of a chuck claw according to one embodiment of the present invention.

FIG. 5 is a block diagram of an electric circuit of the lead frame transfer device according to one embodiment of the present invention.

6A is a diagram showing a pickup operation of a lead frame according to an embodiment of the present invention. FIG. 6B is a diagram showing a pickup operation of a lead frame according to an embodiment of the present invention. (D) Pick-up operation of lead frame according to one embodiment of the present invention (e) Pick-up operation of lead frame according to one embodiment of the present invention

FIG. 7A is a diagram illustrating a lead frame pickup operation according to an embodiment of the present invention. FIG. 7B is a diagram illustrating a lead frame pickup operation according to an embodiment of the present invention. Operation diagram (d) Pickup operation diagram of lead frame according to one embodiment of the present invention

8A is a diagram illustrating a pickup operation of a lead frame according to an embodiment of the present invention. FIG. 8B is a diagram illustrating a pickup operation of a lead frame according to an embodiment of the present invention.

FIG. 9 is a front view of the conventional lead frame transfer device during chuck operation.

[Explanation of symbols]

 5 Lead frame 15 Moving table 16 Motor 21 Cylinder 24 Ball screw 25 Motor 27 First nut 29 Second nut 32 Pulse motor 34 Cam 39 First chuck jaw 42 Cam follower 47 Second chuck jaw

──────────────────────────────────────────────────続 き Continuation of the front page (56) References JP-A-4-275440 (JP, A) JP-A-63-5536 (JP, A) (58) Fields investigated (Int. Cl. ⁷ , DB name) H01L 21/50

Claims (1)

(57) [Claims] 1. A first chuck jaw and a second chuck jaw for chucking a lead frame from right and left, and a lead frame stacked and stacked on the first chuck jaw and the second chuck jaw to move up and down. Lifting means for operating,
Opening and closing means for opening and closing a first chuck jaw and a second chuck jaw to chuck and release the lead frame; and a state in which the lead frame is chucked by the first chuck jaws and the second chuck jaws. Up-and-down moving means for relatively moving the first and second chuck claws up and down, and moving means for moving the first and second chuck claws which have chucked the lead frame to predetermined positions. A lead frame transfer device, comprising: