Abstract: A method and apparatus for controlling the feed speed of a machine in a numerical control system having a manual pulse generator for generating pulses in response to a manual operation. The numerical control system numerically controls the machine by supplying the machine with the generated pulses as feed pulses in a manual feed mode and with feed pulses corresponding to a commanded feed speed in modes other than the manual feed mode. The commanded feed speed is modified in accordance with an override quantity stored in a register. The method includes selectively designating the modes other than the manual feed mode, changing the override quantity, which is stored in the register, based on the pulses generated by the manual pulse generator and in accordance with the designated mode, and modifying the commanded feed speed in accordance with the override quantity stored in the register.

Abstract: A numerical control method for moving a tool along a commanded curve on a curved surface, which includes entering the curved surface defined by data representing a mathematical expression or by a group of numerical data, entering numerical control data specifying a projected curve obtained by projecting the commanded curve onto a predetermined plane, successively finding positional coordinates on the commanded curve through use of the curved surface data and numerical control data specifying the projected curve, and controlling the position of the tool on the basis of the positional coordinates.

Abstract: Ordinarily, an interpolator (102) executes pulse calculations on the basis of a movement command from a command tape (101), to generate the respective distributed pulses XP, YP, ZP, BP and CP of cartesian coordinate axes and spherical coordinate axes, and these pulses drive corresponding servomotors (113)-(117) through servo circuits (108)-(112). In order to keep the relative position between the nose of a tool and a workpiece unchanged in a manual operation, a tool holder is positioned in the cartesian coordinate system, whereupon manual pulses in the B-axial or C-axial direction are generated by a manual pulse generator (103). Then, the distributed pulses BP and CP are generated through the interpolator (102) and rotate the servomotors (116) and (117). The distributed pulses are simultaneously impressed on a compensation circuit (104), which calculates the compensation pulses XHP, YHP and ZHP so as to drive the servomotors with pulses obtained by adding the compensation pulses to the distributed pulses.

Abstract: A method and apparatus for sensing the present position of a movable machine element in a position control system when a position control loop in the system is placed in the open state. In the position control system, error storage means computes and stores an error which corresponds to the difference between a command value produced by a control unit and an amount of movement sensed by a position sensor provided on a motor shaft or on the movable machine element. A speed control circuit controls the motor in accordance with the error from the error storage means.

Abstract: Position error correction equipment with which it is possible to perform a backlash correction or a pitch error correction with a high degree of accuracy even if the state of a numerical control machine tool, for instance, temperature, varies. Error correction data groups predetermined by measurement in respective states of the numerical control machine tool are stored in an error storage circuit (MEM) corresponding to the respective states. An error correction data selecting circuit (MPX) selects an error correction data group corresponding to a particular state of the numerical machine tool from the error correction data groups stored in the error storage circuit (MEM). A position correcting circuit (CPG) carries out a position correction by adding a correction pulse to a command pulse or feedback pulse from a position detector through utilization of the error correction data group selected by the error correction data selecting circuit (MPX).

Abstract: A numerical controller having an extended optional block skip function which permits selection of an optional block in a certain specific section of an execution program. In a numerical information storage medium is stored a cutting program in which a specific block is provided with skip object indicating information and skip select information, which is data for deciding whether to skip over the block and which can assume at least two values. Information indicating which ones of the blocks specified as the objects of optional block skip control are to be validated and invalidated is entered from a block select switch. A block skip circuit checks whether or not the skip object indicating information is present at the head or intermediate portion of each block. If not, the block is selected and, if the information is present, the skip select information is collated with information from the block select switch.

Abstract: A numerical control system in which a numerical control device is adapted to control a machine tool equipped with a plurality of tables, as one example, on which workpieces may be secured to be machined by a tool mounted on a head. A table which is not being controlled automatically by the numerical control device can be operated independently of the automatic operation network of the numerical control device and placed in a manual operation mode or manual data input mode in which the table can be moved manually even while the numerical control device controls the other table or tables automatically.

Abstract: A data input device equipped with a keyboard including a plurality of keys at least some of which are assigned both a letter of the alphabet and a numerical value, which keys are operated to generate signals representing data that comprises a letter of the alphabet and numerical values immediately following the letter. The initial operation of one of the keys produces the data indicated by the letter of the alphabet assigned to that key, and subsequent operation of the keys produces the data indicated by the numerical values assigned to the keys that have been operated.

Abstract: A method and apparatus for deleting a file from a bubble cassette memory. A file, constituting one input unit of data to be written into the cassette memory, is divided into a plurality of blocks each comprising a predetermined number of bytes and is thereafter stored in the cassette memory. In similar fashion a plurality of such files are stored in the cassette memory in numerical order. When a command for deletion of the n-th file F.sub.n is generated, files which were originally stored in the cassette memory following the n-th file F.sub.n are stored successively and in block-by-block fashion in the cassette memory starting from the position at which the n-th file F.sub.n was originally stored.

Abstract: A system for numerically controlling a machine tool comprising a plurality of machine tools, a plurality of numerical control circuits and a computer as an entirely automatic operation commander device, for carrying out the control of the entire processes of said plurality of machine tools with a central control station.

Abstract: A method for carrying out a cutting work using the numerical data obtained from a tracing of a model by stylus means, said numerical data being obtained by applying a proportional allotment to a first and second numerical data related to a first and a second stylus, in accordance with the radius of the cross-section of a cutting tool.

Abstract: The time for positioning of a machine under numerical control is determined so that the positioning is finished at the moment when the amplitude of vibration of the machine is reduced to zero. In the thus predetermined time at least accelerating control and decelerating control are conducted to achieve control for positioning the machine at a commanded position.