Patent ID: 8047093

Claim:
A parallel robot comprising: a base section; a movable section capable of moving with respect to said base section; a movable-section drive mechanism having a parallel mechanism configuration and provided between said base section and said movable section, said movable-section drive mechanism operating to allow said movable section to perform a three-axis translational motion with respect to said base section; a wrist section provided rotatably in said movable section; and a wrist-section drive mechanism operating to allow said wrist section to perform a rotational motion with respect to said movable section; wherein said wrist-section drive mechanism comprises: a hollow outer holder connected to said base section and rotatable about a first rotation axis; a hollow intermediate holder provided inside said outer holder and rotatable about a second rotation axis orthogonal to said first rotation axis; a hollow inner holder provided inside said intermediate holder and rotatable about a third rotation axis orthogonal to said second rotation axis; a prime mover driving said outer holder to rotate about said first rotation axis through a power transmission element, said prime mover arranged outside a holder assembly configured by assembling said outer holder, said intermediate holder and said inner holder; and a rod-shaped transmission member received in said inner holder and linearly movable in a rotationally restrained state along a linear-motion axis orthogonal to said third rotation axis, said rod-shaped transmission member being connected, at one end thereof spaced from said inner holder, to said wrist section through a universal joint; wherein said transmission member operates to transmit a rotation of said outer holder about said first rotation axis to said wrist section through said universal joint, and to allow said wrist section to perform a rotational motion about a fourth rotation axis orthogonal to said third rotation axis and different from said linear-motion axis; and wherein said outer holder is carried on said base section, and said prime mover is carried on said base section adjacently to said outer holder so as not to protrude beyond said outer holder in a direction away from said movable section.