Abstract: A gear pitch error correcting system for a numerical control apparatus used for a machine tool including at least one pair of gears provided in a transmission line through which the rotating force of a servomotor is transmitted to a driven member. Gear pitch error correction values for the respective gears, which each correspond to a predetermined gear angle and collectively cover one gear rotation, are stored in a nonvolatile memory. A pitch error computing means (E) refers to a current position register (D), reads out pitch error correction data (14b) corresponding to the current position from the nonvolatile memory, and adds up the data to obtain a superimposed pitch error correction value. The superimposed pitch error correction value and an interpolation pulse from an interpolating means (B) are added together by an adder (C), to obtain a pitch error-corrected output pulse, which is then supplied to an axis control circuit (18).

Abstract: Disclosed is a numerical control apparatus for controlling a numerically controlled machine tool such as a hobbing machine and the like. An axis control circuit (14) provided with a synchronization control means (8) controls the rpm of a spindle motor (5) and the rpm of a servo motor (11) based on feedback pulses supplied from a position coder (7) connected to a hob axis (3), so that a ratio of the rpm of the hob axis (3) to the rpm of a C-axis (13) has a given value. A first internal counter (15a) monitors the number of feedback pulses supplied from the position coder (7) and a second internal counter (15b) monitors the number of pulses distributed to the C-axis (13), and when a ratio of the rpm of the hob axis (3) to the rpm of the C-axis (13) is to be changed, a correction pulse calculation means (9) calculates correction pulses based on the number of rotation pulses of the hob axis (3) and the number of the rotation pulses of the C-axis (13) counted by the first and second internal counters (15a, 15b).

Abstract: An involute interpolation error correcting method corrects an error on involute interpolation in a numerical control system for machining gears and pump vanes. The method corrects an insufficient cut in an actual configuration of a workpiece which is machined along a first involute curve (In1) that is commanded. A radius of curvature (Rs) from a base circle (C) to a starting point (Ps3) of the insufficient cut on the first involute curve (In1), and an error (De) which occurs at an ending point of the first involute curve (In1) in a direction normal to the insufficient cut, are determined from the machined configuration, and set as parameters in the numerical control system. On interpolation from the starting point (Ps3) of the insufficient cut to the ending point (Pe1) of the first involute curve, a first offset at the time the first involute curve is interpolated is changed to a second offset which is increased from the first offset by the error (De).

Abstract: A feed speed control method for a numerical control device in which a feed speed of a tool traveling along an instructed machining path is controlled in accordance with a machining program. The speed of each axis is derived (S2), and the acceleration of each axis is derived from a speed variation between adjacent blocks (S3). When the acceleration (.DELTA.Vx) is larger than a permissible acceleration (.DELTA.Vxmax) (S4), first ratios (K1) of the permissible accelerations to the accelerations are derived for individual axes (S5), and the smallest of the first ratios is selected. The command speed is multiplied by the square root of the smallest first ratio to derive an actual feed speed (S9). In this way, shock to a machine is reduced and an excessive load on a servomotor is reduced even when blocks continue for successive infinitesimal distribution distances, as in the case wherein a curve is approximated by the use of straight lines.

Abstract: A spline interpolation method of subjecting given points to interpolation by using a cubic spline curve is provided. A first-derivative vector is derived from a preset number of points including a starting point (P.sub.1), and a cubic equation between the starting point and a next point is derived based on the coordinate values of the preset points including the starting point (P.sub.1) and the extreme point condition of the starting point (P.sub.1), to derive a spline curve between the starting point (P.sub.1) and a point (P.sub.2) next to the starting point (P.sub.1). Next, the first-derivative vector at P.sub.2 and a new next point are used instead of the starting point (P.sub.1), to derive a cubic curve between P.sub.2 and P.sub.3.

Abstract: An involute interpolation error correction system for correcting an error attributable to an involute interpolation of a numerical control device or the like. When machining is effected in accordance with a command for an involute curve (In1), a bite is produced in an actual work shape in the vicinity of a basic circle (C). The start point (Ps3) of this bite, the radius (Rs) from the basic circle (C) and an error amount (De) in the normal direction of the bite are obtained from the work shape, and this data is set as parameters in the numerical control device. The numerical control device allows a cutting along the involute curve (In1) up to the point Ps3, and then cuts along an involute curve (In3) having an end point which is deviated from the point Ps3 by the error amount (De) in the normal direction, whereby a bite-free involute curve machining can be effected.

Abstract: A method of correcting a machining program for a numerical control device during an execution of the program is provided. A created machining program, which is stored in a memory (5), is executed for a program check, a single block stop is effected at a portion (2) at which an error is found in the machining program, and the machining program is executed in reverse to a predetermined block (P1). Then the machining program is corrected and executed. Accordingly, it is not necessary to return to the beginning of the machining program for a reexecution thereof, and thus the machining program can be efficiently corrected.

Abstract: A numerical control apparatus according to the invention for interpolatory control of a tool along the shape of a workpiece to be machined. In order to perform offsetting of a cutting tool by an amount equivalent to the tool diameter when involute interpolation is carried out, an involute curve is approximated by a circular which is set in dependence upon the intersection angle of a machining trajectory at a command point commanding the start of machining.

Abstract: An involute interpolation method for machining operations is used in a numerical control apparatus.A rotational direction (G03.1) of an involute curve, an incremental distance along the involute curve or an incremental angle, a center position (X.sub.0, Y.sub.0) of a base circle and a radius (R) of the base circle are obtained per the instruction. The involute curve is interpolated using a predetermined distance or predetermined angle.The above processing is executed with a numerical control apparatus and pulse distributions are continuously carried out. Therefore, the involute curve can be interpolated without need for a special program producing system.

Abstract: An involute interpolation method for use in machining by a numerical control apparatus.A rotational direction (G03.1) of an involute curve, coordinates of an end point (Xe, Ye), a center position (I, J) of a base circle as viewed from a start point, and a radius (R) of the base circle are instructed, from two equations representing the involute curve sequence of points are obtained, and interpolation of the involute curve is performed while interpolating those points in a range of the angle .theta. corresponding to the start point on the involute curve to the end point thereon.The increment of .theta. is decremented in proportion to the increment of the angle owing to the factor K/ (R.multidot..theta.), so that the interpolation is performed in such a manner that the speed in the tangential direction is made at constant, whereby a machining speed of the involute curve is maintained at constant.

Abstract: Data accommodated in a plurality of successive blocks specified by a registration command is converted into an execute form and prestored in storage means. In response to an execution command, control is performed in accordance with the stored data. In the case of executing in succession a plurality of blocks each having a short execution time, data in the blocks is converted into the execute form and stored. This eliminates the time for the data conversion, and hence permits continuous movement of a movable machine part.

Abstract: This invention provides a sizing agent (A) to be used in neutral range in papermaking, the sizing agent being characterized in that it is an aqueous dispersion of a reaction product prepared by reacting, in a specific proportion, (i) a rosin compound and (ii) at least one polyhydric alcohol selected from among a trihydric alcohol and a tetrahydric alcohol both consisting of carbon, hydrogen and oxygen, and a sizing method using the sizing agent (A) in neutral range at a pH of about 6 to about 9 in papermaking. And this invention further provides a sizing agent (B) to be used in neutral range in papermaking, the sizing agent being characterized in that it is an aqueous dispersion of a reaction product prepared by reacting, in a specific proportion, (i) a rosin compound, (ii) at least one polyhydric alcohol selected from among a trihydric alcohol and a tetrahydric alcohol both consisting of carbon, hydrogen and oxygen and (iii) a .alpha.,.beta.

Abstract: A data input/output system for an application system (AS) which is provided with a processor (6) and a memory (8) therefor and is connected to numerical control equipment (NC) to take partial charge of its NC functions. The data input/output system makes it possible for the application system (AS) to input thereinto and output therefrom a program via an input/output interface (5) provided on the NC side, and to command the NC from the application system (AS) side. A receiving circuit (9 to 15) receives a program delivered from an NC processor (3) and a transmitting circuit (9 to 15) transmits to the NC processor (3) the program stored in the memory (8) of the application system. Data is input to and output from the application system (AS) via the input/output interface (5) provided in the numerical control equipment (NC).

Abstract: For reliably and easily judging whether or not a cutting locus is correct, which locus has been set in a cutting locus or tool path control program, which program has a step of commanding the rotational angle of a rotary table carrying a workpiece and a step of commanding the locus of a cutter corresponding to each rotational angle commanding step. A rotational angle range for displaying the locus of the cutter is set through a keyboard or the like. A CPU causes a display only if the locus of the cutter is within the set range.

Abstract: An interface unit simplifies the definition or correction of the contents of conversion from a macro instruction into micro instructions by the machine tool maker, without changing the specifications of the NC processor (3) side in numerical control equipment (NC). A receiving circuit (9, 10) receives a macro instruction delivered from the NC processor (3), and format converting circuitry (6, 8) converts the macro instruction received by the receiving circuit (9, 10) into a series of micro instructions. A transmitting circuit (11, 12) transmits the series of micro instructions obtained by the format converting circuitry (6, 8) to the NC processor (3).

Abstract: Equipment for a numerical controller is provided, for measuring the distance of travel of a tool through utilization of a skip function of a numerical controller and reducing a delay in detecting a skip signal thereby ensuring high precision measurement of the distance of travel. Position storage memory accumulates distribution command values, which are generated within a predetermined period, and second storage memory stores a stored value P.sub.0 of the position storage memory directly before the execution of a distance measurement function code. A time counter is counted up by pulses which have a period shorter than the predetermined period and are applied thereto from a pulse generator, via a gate circuit, wherein the time counter is cleared within the predetermined period. Upon input of the skip signal, the gate circuit stops the supply of the pulses to the time counter.

Abstract: An interface unit is connected beween a numerical controller (NC) and an electric power control circuit (PC). The interface unit includes an actual speed memory (50) into which the numerical controller (NC) can write actual speed data and from which the electric power control circuit (PC) can read out the written data, and a corrected speed memory (51) into which the electric power control circuit (PC) can write corrected speed data and from which the numerical controller (NC) can read out the written data. This makes it possible for the electric power control circuit (PC) to detect the actual speed of the numerical controller (NC) by reading out the actual speed memory (50), and to control the actual speed of the numerical controller (NC) by writing the corrected speed data in the corrected speed memory (51).

Abstract: A numerical control apparatus wherein a stored stroke limit range is displayed (S1) on a graphic display unit. An NC machining program is read out block by block to draw a locus of a tool on the graphic display unit (S2, S3, S4). The drawing is stopped and a message is displayed (S8) when the locus of the tool falls outside (S5) the stored stroke limit range.