Robot and robot system

A robot system comprising:

• a robot;
• and
• a control device that controls driving of the robot, wherein
• the robot includes
• a base,
• a first arm that is joined to the base and that rotates around a first rotation axis with respect to the base,
• a second arm that is joined to the first arm and that rotates around a second rotation axis, which is parallel to the first rotation axis, with respect to the first arm,
• a work head that includes a spline shaft which is disposed at the second arm and which is disposed along a third rotation axis parallel to the first rotation axis and a spline nut which is mounted on the spline shaft, and in which the spline shaft rotates around the third rotation axis when the spline nut is rotated, and
• a spline shaft first drive mechanism that rotates the spline nut to rotate the spline shaft around the third rotation axis,
• the spline shaft first drive mechanism includes a motor and a power transmission mechanism that transmits rotation of the motor to the spline nut,
• the power transmission mechanism has a first pulley that is fixed to a rotation shaft of the motor, a second pulley that is fixed to the spline nut, an intermediate pulley that is supported by a support member via a bearing and that rotates around a fourth rotation axis, which is parallel to the first rotation axis, with respect to the second arm, a first belt that is wound around the first pulley and the intermediate pulley, and a second belt that is wound around the intermediate pulley and the second pulley,
• the intermediate pulley has a first intermediate pulley around which the first belt is wound, a second intermediate pulley that is disposed side by side with the first intermediate pulley in a direction along the fourth rotation axis and around which the second belt is wound, and a shaft portion that is disposed along the fourth rotation axis and that couples the first intermediate pulley and the second intermediate pulley, and is supported by the support member via the bearing at the shaft portion,
• one of the first intermediate pulley and the second intermediate pulley has a recess portion that is open to another side and into which the shaft portion is inserted,
• at least a part of the bearing is positioned in the recess portion, and
• in plan view from a direction orthogonal to the fourth rotation axis, the bearing and the first belt or the second belt overlap each other.