Parallel link robot arm.

摘要

In a precision operable robot arm comprising four levers (11-14) pivotally connected with each other into a parallel arranged link form, when one ends of first and second levers aligned vertically, for example, are driven respectively by two motors (2, 3) such that the levers are swung around the alignment axis in a horizontal plane, for example, a work supporting device (16) provided at an outwardly extending end of the fourth lever (14) is also moved in a horizontal plane. A first pulley (8) is fixedly secured to a position aligning with the driving shafts (5, 6) of the two motors, while second and third pulleys (17, 18), which are integrally rotatable, are rotatably supported by a pivot pin (15) coupling the second and fourth levers, and fourth pulley (19) rotatably supported at the outer end of the fourth lever is fixed to the work supporting device. First and second belts (21, 22) are extended around the first pulley and the second pulley, and the third pulley and the fourth pulley, respectively, so that the work supporting device is held in the same posture regardless of the movement thereof int he plane.