Abstract: In path control apparatus for a numerically controlled machine tool, a computer determines the trajectory to be traversed in space, resolves the latter by way of interpolation into the axial increments of the individual feed axes and performs complete position control for each axis. The interpolation is accomplished by the method of direct function computation, using travel distance increments proportional to the trajectory velocity. The position control is designed as a discrete control and operates with the premise that the minimum total computing cycle time is shorter than the sampling time of the fastest position control loop required by the control system.

Abstract: An improved numerically-controlled machine tool including means for adding incremental set values, which depend on a programmed input, and incremental actual values, generated by a self-balancing distance measuring system, at defined time intervals to a set distance value and an actual distance value, and means for forming a set speed value for a controller of an input drive by the difference between the set distance value and the actual distance value. The difference between the values is proportional to a lag distance, and the self-balancing distance measuring system comprises an inductive measuring transducer which is fed from a primary side thereof and which generates a secondary error voltage on the secondary side thereof, the magnitude and polarity of which depends on the position of a flux vector generated on the primary side relative to the position of a secondary winding of the transducer.

Abstract: A numerically controlled nibbling machine including means for controlling the feed rate of the work piece with respect to the work tool of the machine and in which the feed distance or travel of the work piece is limited by a release time in which the work tool is disengaged from the work piece according to a predetermined number of strokes of the work tool per unit of time. The improvement of the invention comprises the provision of means for determining the release time of the work tool in a single stroke of the work tool for any number of strokes of the tool, and means for automatically determining the minimum accelerations and decelerations of the work piece required for travelling the feed distance and for forming a desired feed rate value for the work piece from the determined release time of the work tool and the feeding distance of the work piece per stroke.

Abstract: A numerically controlled nibbling machine in which the feed distance of a workpiece is limited by a release time during which a work tool is disengaged from the workpiece according to a predetermined number of strokes of the work tool per unit of time. The nibbling machine includes drive means for the work tool, means for controlling the feed rate of the workpiece with respect to the work tool, means for determining the release time in a single stroke of the work tool for every number of strokes of the tool per unit of time, and means for automatically determining minimum acceleration and deceleration of the workpiece required for travelling the feed distance and for forming a desired feed rate value for the workpiece from the release time and the feed distance of the workpiece. The improvement of the invention comprises the means for determining the release time further comprising switch means disposed in the path of the work tool for generating a stop command signal for the drive means for the work tool.

Abstract: A method for automatically varying the feed rate of a moving workpiece carriage in the proximity of permissible terminal positions for the carriage in a machine tool. The machine tool includes a numerical control means for controlling the position of the workpiece carriage and means for determining the position of the workpiece carriage in the machine tool. The improvement comprises storing signals corresponding to a plurality of safety positions of the workpiece carriage located within the terminal positions of the carriage in a memory device provided in the numerical control means. The safety position signals are then compared with measured position signals generated by the position determining means which correspond to the position of the workpiece carriage in the machine tool. The feed rate of the workpiece carriage is automatically reduced by the numerical control means when the safety positions are passed by the workpiece carriage as the carriage moves in a direction towards the terminal positions.