Verb Frames Extracted from Dictionaries

For lapping the surfaces defining a hole in a wiredrawing die of diamond or artificial material, one or more transducers are excited by respective ultrasonic generators to produce mechanical vibrations imparted to lapping needles. Turntables arranged opposite to the tips of the lapping needles are rotated from a common drive shaft and, simultaneously, each rolled or swayed about an axis passing through the die mounted thereon. A cam or crank mechanism driven from the common drive shaft is employed for the rolling motion of each turntable. The apparatus further comprises means for fine adjustment of the position of each turntable relative to the lapping needle in a plane at right angles therewith, and means for yieldably urging the die on the turntable against the lapping needle under adjustable pressure.