Vertically movable workpiece support device

A vertically movable workpiece support device comprising:

• a parallel link mechanism that supports a workpiece support base so as to be parallelly and vertically movable;
• a raising/lowering drive means that drives the workpiece support base to raise and lower the workpiece support base and the raising/lowering drive means is formed with a drive chain that is bendable to only one side and a driving sprocket wheel that engages with the drive chain and in which the drive chain supports the workpiece support base in a vertically linear path section between the workpiece support base and the driving sprocket wheel;
• the drive chain having a plurality of pairs of left and right links and a plurality of link-to-link rollers pivotally supported between the pairs of links;
• a chain guide plate which contacts a link-to-link roller of the drive chain between a pair of links supporting said link-to-link roller, as said link-to-link roller is turned around the driving sprocket wheel and which sandwiches said link-to-link roller with the driving sprocket wheel;
• a mark is displayed on the chain guide plate, in a position separated at a predetermined distance outward from a turning path of the links in the drive chain;
• and
• a side wall is positioned lateral to the chain guide plate and the side wall pivotally supports the driving sprocket wheel, and an opening is disposed in the side wall for viewing the mark to visually check a distance between the mark and the turning path of the links.