Integrated circuit tester having a fail-safe mechanism for moving IC-chips

An integrated circuit tester which includes a fail-safe mechanism for moving an integrated circuit chip between an initial position where said integrated circuit chip is inserted into said tester and a test position where said integrated circuit chip is actually tested;

• said fail-safe mechanism for moving being comprised of:
• a motor;
• a shaft, coupled to said motor, which has a threaded section that said motor rotates;
• a threaded member which travels linearly along said threaded section of said shaft when said shaft is rotated by said motor;
• a lifter arm, coupled to said threaded member, that moves between predetermined first and second positions in response to said linear travel of said threaded member;
• a linkage means, coupled between said lifter arm and said integrated circuit chip, which places said integrated circuit chip at said initial position and said test position as said lifter arm moves to said first and second positions respectively;
• and, said shaft having first and second unthreaded sections, adjacent to opposite ends of said threaded section, onto which said threaded member linearly travels and stops if said shaft fails to stop rotating when said lifter arm respectively reaches said first and second positions.