| 摘要 |
<p>A work cell (210) for populating a ball grid array (218) employs gravity for tranferring solder balls (221) from a tooling plate (216) to the ball grid array. The tooling plate is positioned on a gantry (211) along with a reservoir (215) for solder balls. The gantry, along with the tooling plate and reservoir, is rotated, in one embodiment, through about one hundred and eighty degrees to spread the solder balls over the tooling plate and to recapture loose solder balls as the gantry rotates. A riser cylinder (219) moves a ball grid array into juxtaposition with the populated tooling plate prior to the point (i.e. angle of rotation) at which gravity operates to drop the solder balls out of the tooling plate. Further rotation results in gravity transfer of the solder balls to a (fluxed) ball grid array. Apparatus (313) employing more than one work cell (316, 317) is also described.</p> |
