Driving Mechanism And Robot

A robot comprising:

• a base;
• a first arm rotatably connected to the base around a first turning axis;
• and
• a second arm rotatably connected to the first arm around a second turning axis;
• the second arm comprising:
• a motor;
• a first pulley configured to rotate around a first axis and connected to the motor;
• a second pulley disposed to be separated from the first pulley and configured to rotate around a second axis parallel to the first axis;
• a first belt laid around the first pulley and the second pulley;
• a third pulley disposed coaxially with the second pulley in a direction along the second axis and configured to rotate around the second axis;
• a shaft extending along the second axis;
• a fourth pulley disposed to be separated from the third pulley, the fourth pulley configured to rotate around a third turning axis that is parallel to the second axis;
• a second belt laid around the third pulley and the fourth pulley;
• a spline shaft inserted through the fourth pulley at least rotatably around a third turning axis;
• a first bearing located between the second pulley and the third pulley and in contact with the shaft, and
• a second bearing in contact with the shaft,
• wherein the third pulley is sandwiched between the first bearing and the second bearing, and
• when the second bearing is viewed along a direction perpendicular to the second axis, the second bearing does not overlap the third pulley.