FORMING CONTOURS

摘要

A control system for an apparatus, such as a machine tool (100), for forming a straight configured contour having co-ordinates in at least two directions (X, Y, Z). The apparatus incorporates a workpiece support (102), a contour forming means (107), and incremental drives (Mu, Mu and Mu) to effect relative movement between the support (102) and the contour forming means (107). The components of the straight configured contour in each of the directions (X, Y and Z) are reduced to the number of nominal increments corresponding to a predetermined distance along the contour. A continuous feed of input pulses is provided to a computer for continuous counting in respect of each direction. A drive pulse is fed to a respective incremental drive (Mu, Mu or Mu) to effect movement in the respective direction (X, Y or Z) each time a predetermined number of respective input pulses have been counted, the predetermined number being inversely proportional to the number of nominal increments relevant to the direction. A curviliner contour may be formed from successive straight configured contours.