Abstract: A support mechanism for supporting thereon a set of upper and lower forming dies to be opened and closed in a forming process. The support mechanism includes a base structure of mounting thereon the lower forming die, a pair of opposed upright side plates fixedly mounted on the base structure in parallel to one another, a pair of guide tracks provided on the respective inside faces of the side plates, a pair of actuators mounted on the base structure at a position adjacent the respective side plates, a movable support frame arranged between the side plates and located above the lower forming die on the base structure for supporting the upper forming die thereon, the support frame having a pair of support shafts secured to its opposite sides and slidably engaged with the guide tracks, and a pair of link mechanisms arranged to support thereon the support shafts of the support frame and to transmit the motion of the actuators to the support shafts to move the support frame along the guide tracks.