JP2001284372A - Lead frame gripper - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a lead frame gripper of a large clamp force. SOLUTION: A lead frame gripper 1 is provided with an upper claw 21 and a lower claw 22, which pinches a lead frame 4 from above and below. The upper claw 21 is provided at an upper claw support plate 23 supported freely vertically, and an arm 26 for an upper claw is projected at the upper claw support plate 23. The lower claw 22 is provided at a lower claw support plate 32 supported freely vertically, and an arm 34 for the lower claw is projected at the lower claw support plate 32. A cam 41 set around a rotary shaft 15 is arranged between the cam follower 28 of an actuating arm 26 for an upper claw and the cam follower 35 of an actuating arm 34 for the lower claw. A large-diameter part 43 is made at the cam 41, and in condition that both cam followers 27 and 35 catch the large-diameter part 43, both arms 26 and 34 shift in the direction, where they separate from each other, and the upper and lower claws 21 and 22 pinch the lead frame 4 from above and from below.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

The present invention relates to a lead frame gripper for holding a lead frame.

[0002]

2. Description of the Related Art Conventionally, a lead frame transport device has
As shown in FIG. 4, a lead frame gripper 102 for holding the lead frame 101 was provided.

The lead frame gripper 102 has an upper claw 111 and a lower claw 112 which hold the lead frame 101 from above and below. The upper claw 111 is supported by a base plate 114 via an upper claw support plate 113 so as to be vertically movable.
Is provided with an upper claw arm 115. The lower claw 112 is supported by the base plate 114 via a lower claw support plate 116 so as to be vertically movable, and the lower claw support plate 116 is provided with an arm 117 for a lower claw. The arms 115 and 117 are
The intermediate portion is urged by a coil spring 118 in a direction approaching each other.

A rotatably supported cam 121 is disposed between the arms 115 and 117. The cams 121 are mounted on the arms 115 and 117, respectively.
Are provided in contact with the cam followers 122, 122. The cam 121 has a large diameter portion 123 and a small diameter portion 124.
Are formed, and the two cam followers 122 and 12 are formed.
2 with both small arms 124 sandwiching the small-diameter portion 124.
5 and 117 are urged by the coil spring 118 so that the lead frame 101 can be held between the upper and lower claws 111 and 112. Further, with the two cam followers 122, 122 sandwiching the large-diameter portion 123, the two arms 115, 117 are moved in a direction away from each other,
The upper and lower claws 111 and 112 are configured to be separated from each other.

[0005]

However, in the lead frame gripper 102, since the clamping force for clamping the lead frame 101 depends on the spring force of the coil spring 118, there is a limit in increasing the clamping force. Was.

The present invention has been made in view of such a conventional problem, and has as its object to provide a lead frame gripper capable of obtaining a large clamping force.

[0007]

In order to solve the above-mentioned problems, a lead frame gripper according to the present invention comprises a lead frame for vertically holding a lead frame between upper and lower pawls movably supported. In the gripper,
An upper claw operating arm that moves up and down with the upper claw is disposed below a lower claw operating arm that moves up and down with the lower claw,
A cam for moving the two operation arms in a direction away from each other during the rotation operation is disposed between the two operation arms.

That is, when the lead frame is clamped between the upper and lower claws, the cam provided between the upper and lower pawl operating arms is rotated to rotate the cam. Move the arms away from each other. Then, the upper claw is moved downward by moving the upper claw operating arm downward, and the lower claw is moved upward by moving the lower claw operating arm upward, and the lead frame is moved. , And are clamped from above and below by the upper and lower claws. At this time, the clamping force of the lead frame by both claws is determined by the bending of each arm.

[0009]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS One embodiment of the present invention will be described below with reference to the drawings. FIG. 1 is a view showing a transport device 2 including lead frame grippers 1 and 1 according to the present embodiment. The transport device 2 moves a strip-shaped lead frame 4 on a transport path 3 from upstream to downstream. It is a device that conveys.

The transport path 3 includes transport rails 11 for supporting the edge of the lead frame 4, and a guide rail 13 for movably supporting a slider 12 is provided on a side of the transport rail 11. It has been extended. A feed screw 1 for moving the slider 12 is provided on the guide rail 13.
The slider 12 can be moved along the transport path 3 by rotating the feed screw 14 by a rotation mechanism (not shown). A rotating shaft 15 that extends through the slider 12 extends between the guide rail 13 and the transport rail 11.
The rotation shaft 15 is configured to be rotated by a rotation mechanism (not shown). A base plate 16 is provided at the tip of the slider 12, and the lead frame grippers 1 and 1 are provided at both ends of the base plate 16.

As shown in FIG. 2, the lead frame gripper 1 has an upper claw 21 and a lower claw 22 which hold the edge of the lead frame 4 from above and below. Both claws 21,2
Reference numeral 2 denotes an L-shaped cross section which is capable of avoiding the transfer rail 11. Carbide portions 21a and 22a made of a cemented carbide are provided at the tips of both claws 21 and 22 to enhance wear resistance. Have been. As shown in FIG. 3, the upper claw 21 is fixed to an upper end of an upper claw support plate 23. As shown in FIG. It is supported on the base plate 16 via guides 24, 24 so as to be vertically movable. As shown in FIG. 3, a balance spring 25 for the upper pawl is provided between the upper pawl support plate 23 and the base plate 16, and the upper pawl support plate 23 is urged in the upward moving direction. ing. At the lower end of the upper pawl support plate 23, an arm 26 for the upper pawl projects as shown in FIG. 2, and a cam follower 27 is pivotally supported at the tip of the arm 26 for the upper pawl. ing. The cam follower 27 is eccentric with respect to the shaft portion 28, and is configured to be able to change the amount of protrusion upward from the upper claw arm 26 by rotating and fixing.

As shown in FIGS. 2 and 3, the lower claw 22 is connected to the lower claw support plate 3 via an L-shaped bracket 31.
The lower pawl support plate 32 is fixed to the lower end of
Is supported by the base plate 16 via a pair of lower claw linear guides 33, 33 disposed outside the upper claw linear guides 24, 24 (see FIG. 1) so as to be vertically movable. . At the upper end of the lower pawl support plate 32, an arm 34 for the lower pawl is provided so as to be located above the arm 26 for the upper pawl.
A cam follower 35 is pivotally supported at the tip end of the cam follower 35. The cam follower 35 is eccentric with respect to the shaft portion 36,
By rotating and fixing, the amount of projection downward from the lower claw arm 34 can be varied. Further, between the lower claw arm 34 and the base plate 16, a lower claw balance spring 37 is provided (see FIG. 2), and the lower claw operating arm 34 is urged in a downward moving direction. ing. As a result, the upper pawl 21 is urged upward by the upper pawl balance spring 25, and the lower pawl 22 is urged downward by the lower pawl balance spring 37. It is configured such that a gap is formed between them.

On the other hand, on both sides of the slider 12, FIG.
As shown in FIG.
41 is rotatably supported. A spline groove 42 is formed in the rotating shaft 15 so that the cams 41 and 41 can be rotated according to the rotation of the rotating shaft 15 while allowing the movement of the slider 12 along the rotating shaft 15. It is configured. The cam 41, as shown in FIG.
The lead frame gripper 1 is disposed between a cam follower 28 of the upper claw operating arm 26 and a cam follower 35 of the lower claw operating arm 34. This cam 4
1, a large-diameter portion 43 and a small-diameter portion 44 are formed.
The cam 41 is rotated and the two cam followers 27 and 35 are rotated.
With the small diameter portion 44 interposed therebetween, the arms 26,
34 is urged by the coil springs 25 and 37,
The upper and lower claws 21 and 22 are configured to be separated. Also, with the two cam followers 27 and 35 sandwiching the large diameter portion 43, the two arms 26 and 34 are moved in a direction away from each other, so that the upper and lower claws 21 and 22 can clamp the lead frame 4 from above and below. It is configured.

In the present embodiment having the above-described structure, when the lead frame 4 is sandwiched between the upper claws 21 and the lower claws 22, as shown in FIG. The cam 41 between the claw operation arm 26 and the lower claw operation arm 34 is rotated to move the two operation arms 26 and 34 in directions away from each other. Then, the upper arm operating arm 26
Is moved downward, the upper claw 21 is moved downward, and the lower claw operating arm 34 is moved upward, so that the lower claw 22 is moved upward. 21 and the lower claw 22 sandwich it from above and below. At this time, the clamping force of the lead frame 4 by the claws 21 and 22 can be given by the bending of the arms 26 and 34. Therefore, the clamping force depends on the urging force of the coil springs for urging the arms 26 and 34, so that a large clamping force can be obtained as compared with the related art in which the increase in the clamping force is naturally limited.

Then, the feed screw 14 is rotated while the lead frame 4 is held, and the slider 12 is moved along the guide rail 13. Then, the lead frame 4 is moved along the transport path 3. At this time, as described above, since the clamping force is increased, slippage between the lead frame 4 and each of the claws 21 and 22 can be reliably prevented, and the feed accuracy of the lead frame 4 can be improved.

[0016]

As described above, in the lead frame gripper according to the present invention, the clamping force of the lead frame by the upper pawl and the lower pawl is used to transfer the operating force of the cam to the upper and lower pawl operating arms. It can be provided by bending. Therefore, since the clamping force depends on the biasing force of the coil spring, a large clamping force can be obtained as compared with the related art in which the increase in the clamping force is naturally limited. Thus, slip during transport of the lead frame can be prevented, and the lead frame feeding accuracy can be increased.

[Brief description of the drawings]

FIG. 1 is a plan view illustrating one embodiment of the present invention.

FIG. 2 is a view corresponding to a cross section taken along line AA of FIG. 1;

FIG. 3 is a view corresponding to a cross section taken along line BB of FIG. 1;

FIG. 4 is a view corresponding to a cross section of a main part showing a conventional lead frame gripper.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Lead frame gripper 2 Transfer device 21 Upper nail 22 Lower nail 26 Operation arm for upper nail 34 Operation arm for lower nail 41 Cam

Claims (1)

[Claims] 1. A lead frame gripper for vertically holding a lead frame between an upper claw and a lower claw supported movably, wherein an operating arm for the upper claw moving up and down with the upper claw is moved up and down together with the lower claw. It is located below the lower arm operating arm that moves,
A lead frame gripper, wherein a cam for moving the two operation arms in a direction away from each other during a rotation operation is disposed between the two operation arms.