Patent ID: 7530287

Claim:
An industrial robot comprising: a first hollow frame; a second hollow frame, wherein the second frame is rotatably connected to the first frame around a rotation axis; a motor fixed to the first frame; a transmission mechanism connected to the motor, provided inside the first frame, and comprising: a drive pulley driven by the motor to rotate, a belt hung upon the drive pulley, and a driven pulley upon which the belt is hung and to which rotation of the drive pulley is transmitted via the belt; a drive mechanism for driving the second frame to rotate around the rotation axis by the drive force transmitted via the driven pulley; a sensor for detecting an abnormality of the transmission of the drive force from the motor to the second frame; a stopper pin supported by one of the first frame or the second frame, the stopper pin enabled to be inserted into a plurality of holes arranged in a circumference around the rotation axis on the other of the first frame or the second frame; and a drive source fixed to the one of the first frame or the second frame, the drive source driving the stopper pin towards the circumference to insert the stopper pin into any one of the plurality of holes to engage the first frame and. the second frame when the sensor detects an abnormality of the transmission of the drive force.