Drive device and substrate processing system

A drive device, comprising:

• a case;
• a first motor having an output shaft extending along a first axial line in the case, the output shaft including an outer peripheral surface having a rib formed in a spiral shape;
• a second motor having an output shaft extending along a second axial line parallel to the first axial line in the case, the output shaft including an outer peripheral surface having a rib formed in a spiral shape;
• a first output shaft including a first shaft body and roller followers, the first shaft body having a cylindrical shape extending along a third axial line extending in a direction perpendicular to the first axial line and the second axial line between the first axial line and the second axial line, the first shaft body having one end protruding to extend outside the case and the other end accommodated in the case, the roller followers being installed on an outer peripheral surface of the other end and engaged at a predetermined reduction gear ratio with the rib of the first motor;
• a second output shaft including a second shaft body and roller followers, the second shaft body being installed coaxially with the first shaft body to pass through an inner hole of the first shaft body, the second shaft body having one end protruding to extend outside the case and the other end protruding to extend from the inner hole of the first shaft body into the case, the roller followers being installed on the other end of the second shaft body and engaged at a predetermined reduction gear ratio with the rib of the second motor;
• a first sealing member located between the case and the outer peripheral surface of the first shaft body;
• and
• a second sealing member located between an inner peripheral surface of the first shaft body and an outer peripheral surface of the second shaft body.