Apparatus for automated loading of wafer cassette

摘要

An apparatus for preventing the over-tilt of a gripper assembly in a cassette loading device is described. The apparatus provides an additional sensor arm system rigidly mounted to the gripper assembly such that the additional sensor arm not only provides a method for it to reach an over-tilt position, but also provides a mechanical stop to manually stop the gripper assembly from making further motion beyond the maximum downward-tilt position of the arm. The apparatus may further be provided with a warning system and a manual override device such that a machine operator may be alerted of the over-tilt condition and further, may manually override the sensor system by temporarily restoring power to the gripper assembly and returning it to a safe position.