An intermittently rotary workpiece-holding table has operating units that move vertically relative to the table. The operating units are controlled by vertically swinging levers that are driven vertically at one end and at their other ends control the operating units. The levers pivot about fulcrums, each lever having two fulcrums spaced apart along its length. During a first portion of movement of the lever, that fulcrum is operative which gives the most rapid vertical movement to the operating unit. Then the first fulcrum becomes inoperative and the second fulcrum becomes operative, whereupon the speed of vertical movement of the operating unit slows, as for example for the performance of a work operation. The same pattern of movement is followed on the return stroke: first there is a relatively slow vertical movement of the operating unit in the opposite direction, followed by a relatively rapid return vertical movement, as the lever pivots successively about the two fulcrums in the reverse order of the initial operation.
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