摘要 |
A plurality of vertically extending cylinders are formed in the interior of a chuck body providing a chucking face on its lower surface. Pistons, in which permanent magnets are embedded, are vertically movably provided in respective ones of the cylinders. When compressed air is introduced into upper portions of the cylinders, the pistons are downwardly displaced so that the permanent magnets are relatively approached to the lower surface of the chuck body. Thus, the chucking face is supplied with magnetic force exceeding a prescribed level, to attract a holder holding electronic component chips, for example. When compressed air is introduced into lower portions of the cylinders, on the other hand, the pistons are upwardly displaced so that the permanent magnets are relatively separated from the lower surface of the chuck body. Thus, the chucking face is supplied with no magnetic force exceeding the prescribed level, so that the holder is separated from the chuck body. |