Secondary positioning device for workpiece machining

摘要

A large machining apparatus for working a substantially planar workpiece such as a metal plate in relation to which a set of work actions, such as machining grooves and holes, is required at one of a number of work zones on or in the workpiece, the apparatus including: a working assembly such as a drop down drill movably mounted on a beam for reciprocal linear movement along a first horizontal axis extending parallel to the longitudinal axis of the workpiece; and an assembly rail movably mounted on the beam at right angles to the beam to carry the working assembly. The apparatus further includes: an immobilizing base mounted on the rail for reciprocal linear movement along the assembly rail in the direction of a second axis and a clamping base mounted on the immobilizing base and adapted to be clamped onto the workpiece to locate the working assembly at a predetermined one of said work zones; and a movable base mounted on the assembly rail for limited reciprocal linear displacement along the assembly rail in the direction of the second axis relative to the immobilizing base. The working assembly is mounted on the movable base to enable limited linear displacement of the working assembly in the second axis direction in the predetermined work zone.