| 摘要 |
A system for handling stiff but flexible discs, particularly semiconductor wafers, including fail safe mechanisms that prevent the disc from being dropped if power to the unit is interrupted. Also, the electronics controlling operation resumes functioning at the point in the operation cycle existing when power was interrupted. A wafer hand assembly member is slipped under a wafer, or between parallel stacked but spaced wafers, and one or more fingers are rotated 90° to a position perpendicular to the plane of the stiff hand assembly member. The hand assembly also has one or more posts positioned perpendicular to the surface of the hand assembly. The finger(s) and post(s)or rear barrier constitute three upright projections or points forming the corners of a triangle with the wafer to be grasped there between. A translator solenoid or voice coil, controls the lateral location of one finger or post, moving that finger or post toward the other two stationary fingers or post(s) causing the wafer to be grasped with controlled traction force between the fixed posts and the moveable finger. The traction force is controlled by the amount of driving energy fed to the translator solenoid. If the power to the solenoid or voice is interrupted, springs in the system cause the disk to be held between the posts or barrier and fingers until power is restored.
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