Abstract: A numerical control apparatus enables a tool to move parallel or vertical to a designated shape to easily carry out a machining of a prototype using general-purpose machine tools. A graphic storing device displays guidance information on a display unit through a graphic control circuit and also stores a designated shape such as an oblique straight line or a circular arc entered by the operator through a keyboard in an interactive fashion. On the detection of a pulse signal HP from a manual pulse generator, an interpolation device reads a changeover signal H/V for commanding one of the parallel movement or the vertical movement of the tool from a changeover device. Then, the interpolation device outputs an interpolated pulse signal CP corresponding to the pulse signal HP and changeover signal H/V in accordance with the designated shape stored in the graphic storing device and supplies the interpolated pulse signal HP to an axis control circuit.

Abstract: On a screen, a shape is specified by inputting the figure data (I, J, R) specifying the shape, and a zone is specified by specifying at least one side (limit region 0) of the zone divided by contour of the shape. With this method of specifying a zone, the movement zone or the prohibition zone of the moving part being controlled can easily be specified without strictly defining as numerical data the position information about the aftermove position or the movement limit of the moving part to be controlled.

Abstract: A numerical control apparatus in which tool feed can be stopped at the same time as machining is completed. An interpolating device in a numerical control apparatus interpolates a pulse signal HP supplied from a manual pulse generator and outputs an interpolated pulse signal CP so that the tool is moved along a designated shape prestored in a graphic data memory device. An axis control circuit generates speed commands for respective axes in response to the interpolated pulse signal CP and sends the generated commands to a servo amplifier. The servo amplifier delivers a drive current I to energize servomotors mounted on a machine tool. A load determination device detects the drive current I from the servo amplifier and determines whether the detected current I decreases at a given ratio. When the drive current I decreases, for example, by 5%, a drive stop signal S is supplied.

Abstract: A cutting tool stop-control apparatus according to the invention is for controlling the stopping of a cutting tool when executing a hole drilling operation by a machining center or milling machine, and particularly when executing a back-boring operation. When the tool is subjected to an emergency return, depending on the actual conditions which prevail when an operation is suspended, the tool is withdrawn to the cycle starting point along an optimum path in accordance with a continuance program, and the prescribed operation is resumed automatically after the tool is changed.