| 摘要 |
PURPOSE:To improve the accuracy of installation as well as to cut down the hours of working by a method wherein a pyramid-shaped recessed part is provided on the lower end face of the outer collet surrounding the inner collet, and a pellet is pulled up by attracting it to the nozzle protruding from the lower end of the inner collet, thereby enabling to properly maintain the pellet by controlling its position using the pyramid-shaped recessed part. CONSTITUTION:The collet 8 is lowered with its own weight by opening a vacuum hole 12 and it is brought to come in contact with a pellet 6 by protruding an attracting nozzle 10 to the lower direction from the outer collet 9. When the pellet 6 is attracted to a vacuum hole 11, the pellet does not come in contact with the guide 9c of the outer collet 9. Accordingly, the pellet 6 can be attracted without giving effect on the other pellets even when the pellet interval is small. As the nozzle 10 is made of soft material such as Si rubber and the like, no damage is given to the surface of the pellets. When a pellet is attracted to a vacuum hole 12 following the vacuum hole 11, the inner collet 8 is raised by a cylinder 9a, and it is supported by the guide 9c in such a manner that its position is adjusted to the pyramid-shaped surface of the collet 9. The above is conveyed to a lead frame by an arm 4, and it returns to the original position and restores to the original state after installation. According to this constitution, the accuracy of installation can be improved and the hours of work can also be reduced. |
