Four-Motion Joint With Oval Guides 3D model

Round turnnions b of link 3 turn and slide along oval guides a of link1. Square body c of link 2 fits into the square hole of link 4 which has square turnnions d. Link 2 has prongs e with square holes sliding along trunnions d. With respect to each other, links 1 and 2 accomplish one turning motion about axis y-y, and three translational motions along perpendicular axes x-x, y-y and z-z.