Two dimensional drive system

A two dimensional drive system, comprising:

• a pair of first linear guides provided in a first direction;
• a pair of second linear guides provided in a second direction perpendicular to the first direction;
• a pair of first travellers respectively engaged with said first linear guides, said first travellers being capable of moving in the first direction along said first linear guides;
• a pair of second travellers respectively engaged with said second linear guides, said second travellers being capable of moving in the second direction along said second linear guides;
• a first ball bearing screw being provided in the first direction, said first ball bearing screw rotatably extending between said second travellers;
• a second ball bearing screw being provided in the second direction, said second ball bearing screw rotatably extending between said first travellers;
• a slider being screwed with said first ball bearing screw and said second ball bearing screw, said slider being capable of moving in the first direction and the second direction on said first ball bearing screw and said second ball bearing screw with rotation thereof;
• a first motor for driving said first ball bearing screw, said first motor being provided on one of said second travellers;
• a second motor for driving said second ball bearing screw, said second motor being provided on one of said first travellers;
• first restraining means for restraining the inclination of said first ball bearing screw with respect to the first direction;
• and
• second restraining means for restraining the inclination of said second ball bearing screw with respect to the second direction;
• said first restraining means comprises:
• a pair of first racks being respectively provided in parallel to each of said second linear guides;
• a first shaft being provided in the first direction, said first shaft rotatably projecting through said second travellers;
• and
• a pair of first pinions being respectively fixed at each end of said first shaft, said first pinions respectively engaging with each of said first racks, and
• said second restraining means comprises:
• a pair of second racks being respectively provided in parallel to each of said first linear guides;
• a second shaft being provided in the second direction, said second shaft rotatably projecting through said first travellers;
• and
• a pair of second pinions being respectively fixed at each end of said second shaft, said second pinions respectively engaging with each of said second racks.