Abstract: Disclosed is a digitizing method of sensing an amount of displacement of each axis applied to a stylus by a tracer head, profiling a model surface while controlling the stylus in such a manner that the amount of displacement is made equal to a reference amount of displacement, sequentially fetching positional data by a predetermined method, and outputting NC data, wherein a difference between the amount of displacement and the reference amount of displacement is monitored, and the difference is added to the positional data and a specific positional data obtained when the difference exceeds a predetermined value is output. Although the amount of displacement of each axis is controlled to be equal to the reference amount of displacement when a gently inclined configuration is profiled, at the moment when a corner is reached, a phenomenon that the stylus is spaced apart from a model arises so that the difference between the amount of displacement and the reference amount of displacement is increased.

Abstract: In a trace control method used for machining a workpiece by tracing a model with a tracer head, the path and speed of two axes (X- and Y-axes) are controlled by NC commands, but, three axes (X-, Y- and Z-axes) are controlled to carry out the tracing operation. An NC command speed (F) is changed by an override circuit (2b) so that the NC command speed coincides with the composite speed of the three axes controlled to carry out the tracing operation, and the resultant speed (Fd) is supplied to an interpolator (2a). The direction of movement along the X- and Y-axes is controlled by the NC command and the speed is affected by the tracing operation. Thus the trace control method can control movement as though all three axes are controlled by NC commands.

Abstract: A tracing control system machines a workpiece to a desired contour corresponding to the surface of a model which is being traced. The tracing control system comprises a tracing control circuit, a digitizing circuit, and numerical circuits. The tracing control circuit controls a plurality of tracing axes to trace the surface of the model. The digitizing circuit is connected to the tracing control circuit through a bus, for reading the positions of the tracing axes as positional data from time to time and processing the positional data to prevent a cutter head from biting into the workpiece, thereby to generate NC data linearly approximate the surface of the model. The numerical control circuits are connected to the digitizing circuit through the bus, for positionally controlling as many machining axes as the number of the tracing axes on the NC data to machine the workpiece.

Abstract: A rotating body tracing control apparatus which performs a tracing while rotating a model and a workpiece. A plurality of point coordinates (P1 or P10) are set on the outer peripheral surface of the model (6), which points depend on a position of the central axis of the rotation and the angle of the rotating axis of the rotation, and a tracing is executed by using a line connecting the individual points (P1 to P5, P6 to P10) as a potential line. Therefore, even when tracing a model, such as a groove of a cylindrical cam having a shape which varies along the central axis of a rotating body, only the groove region can be set around the potential line, and thus the tracing time can be shortened and the groove alone can be treated with a high accuracy.

Abstract: A tracing control system for machining a workpiece through tracing by calculating speed command values of respective axes, using change amounts detected by a tracer head, and moving a cutter relative to the workpiece through control of the speed of the respective axes in accordance with the speed command values. The system is provided with calculating means for calculating predetermined values in proportion to amounts of change in the speed command values of the respective axes, and a U-axis motor and a W-axis motor for moving only a model in parallel with the above respective axes by amounts corresponding to the respective predetermined values. A sub-table, on which only the model is placed is provided on a main table of a tracing machine tool, is moved in the same direction as the direction of movement of the main table, by an amount proportional to the amounts of change in the speed command values, for example, the amounts of delay in the reactions of the servo systems.

Abstract: A digitizing method for digitizing model surface data by tracing a model (MDL) with a stylus (STL) is described. At the time of digitizing, a time (T) required for predetermined conditions to be satisfied and stylus traveling distance (.DELTA.L) during this time are monitored, tracing velocity (F) is obtained based on this time and traveling distance, and the tracing velocity is output along with data indicative of the model surface profile.

Abstract: A tracing control system for machining a workpiece through tracing by calculating speed commands of respective axes, using change amounts detected by a tracer head, and by moving a cutter relative to the workpiece through a control of the speed of the respective axes in accordance with the speed commands. First delay speed commands are obtained from the speed commands (Vx, Vz) at delay circuits (14a, 14c), respectively, and second delay speed commands are obtained at second delay circuits (14b, 14d), respectively, the differences between the first delay speed commands and the above second delay speed commands are calculated, and an X-axis main motor and a Z-axis main motor are driven in accordance with the first delay speed commands, and an X-axis sub-motor and a Z-axis sub-motor are driven in accordance with the calculated differences, thereby move the tracer head.

Abstract: It is arranged for a tracer head (TC) to be rotatable in a rotational direction which adopts, as an axis of rotation, an axis parallel to an axis (e.g., the Y axis) which does not form a tracing plane. When a hollow (HL) having the vertical wall (SL) is traced, the tracer head (TC) is rotated so as not to interfer with a model (MDL), an angle of rotation (.beta.) in the rotational direction is monitored, axial displacements (.epsilon..sub.x, .epsilon..sub.z) along two axes (X, Z axes) other than the axis of rotation are corrected based on the angle of rotation (.beta.), and tracer control is performed using each of the axial displacements obtained by the correction.

Abstract: A digitizing method for obtaining data indicative of the three-dimensional shape of an object by effecting movement along at least one axis (X or Y axis) under numerical control on the basis of path data and along another axis (Z) under tracer control and monitoring the present position along each axis. A numerial control unit performs numerical control to moving a tracer head in X and Y directions. A tracer control unit generates a Z-axis velocity command V.sub.z to move the tracer head along the Z axis. The numerical control unit counts pulses generated by a motor driving a tracer control axis to obtain the present position along the tracer control axis. The numerical control unit also obtains a commanded position along each numerical control axis (X,Y axes) by using the path data, and obtains a present position, represented by a machine position, by substracting an amount of servo-system delay (i.e., the contents of error registers) from the commanded position.

Abstract: There are provided a tracing control apparatus (1), a numerical control apparatus (2), and switching circuits (3X, 3Y, 3Z) for switching and transmitting selectively control instructions from the tracing control apparatus (1) and the numerical control apparatus (2), to a three-axis driving means for the tracer controlled machining (4) and a three-axis driving means for the numerically controlled machining (5) in accordance with selection signals. A numerically controlled machining and tracer controlled machining selection signal (S.sub.C) is used as one of the selection signals besides a tracer controlled machining selection signal (S.sub.A) and a numerically controlled machining selection signal (S.sub.B). When the numerically controlled machining and tracer controlled machining selection signal (S.sub.