device for bestemning of companies of a withdrawal in a bigger piece of the site, foretredesvis

摘要

An apparatus for ascertaining the extent of deviation of the actual position of a hole in a bulky workpiece from the desired position has a mandrel which is reciprocable to move its conical tip into and from the opening. The tip is followed by a main portion which fits snugly into the opening. If the hole is out of position, the mandrel is shifted laterally during penetration of its tip into the hole as a result of sliding movement of the external surface of the tip relative to the surface surrounding the hole. The extent of lateral movement of the mandrel in several direction is monitored by discrete gauges which transmit signals denoting the extent of deviation of actual position of the hole from the desired position in the respective directions. A third gauge can monitor the extent of axial movement of the mandrel into the hole before a collar behind the main portion strikes against the workpiece; such gauge can indicate whether or not the hole is in proper position as considered in the axial direction of the mandrel.