Abstract: Wire electrode type electrical discharge machining equipment is provided with a wire electrode type electrical discharge machining function and a laser machining function. The laser machining is used to effect rough machining at a high machining rate. The electrical discharge machining is used to effect finishing at a high magnitude of precision. The wire electrode type electrical discharge machining equipment is equipped with a laser generator for laser machining, and a column thereof is equipped with laser beam irradiation means which adjoins an upper wire electrode guide and is opposed to a work piece that is to be irradiated with a laser beam. The wire electrode type electrical discharge machining equipment is further provided with a numerical controller which regulates both the machining operation and the relative position of the wire electrode and the work piece as well as the relative position of a laser beam emitter and the work piece along predetermined loci.

Abstract: A wire electrode guide apparatus (1) in a wire-cut electric discharge machine includes a switch valve (80) for supplying pressurized air and preventing the supply of the air to an air pressure-operated actuator (70) for driving a movable piece (40) for three point-support of a wire electrode (3) between the movable piece and a stationary piece. During wire extension, an air supply port (88) of the switch valve is communicated to a switch port (87) thereof through which the pressurized air is supplied to the actuator to move a piston rod (73) of the actuator away from the movable piece to release an urging force acting upon the same, resulting in easy insertion of the wire electrode between the stationary and movable pieces. During electric discharge machining, the switch port is disconnected from the pressurized air supply port to prevent the air supply to the actuator, so that the movable piece is urged by the actuator for wire support.

Abstract: An automatic wire threading method for a wire-cut electric discharge machine is provided, which is capable of permitting a wire electrode to pass through a fine-diameter machining start hole using of a simple arrangement. After an upper wire supporting portion on the wire supply side of a wire transportation system is moved, along with a cut wire, toward a workpiece disposed in alignment with the upper wire supporting portion, so that the leading end of the wire is in a machining start hole, the upper wire supporting portion is moved away from the workpiece, while keeping the wire end in the hole, and the wire is then transported to the wire delivery side of the wire transportation system, thus completing wire threading.

Abstract: To permit machining of a workpiece into a highly accurate tapered configuration, a wire-cutting EDM including a numerical controller that reads programmed shape data is utilized. To precisely taper the workpiece, it is necessary to move the upper and lower guides of the wire so that they start and stop moving simultaneously. From the programmed shape data, the respective speeds of the upper and lower guides are computed. The upper guid is interpolated by the upper guide speed, and the lower guide is interpolated by the lower guide speed so that the guides can start and stop moving simultaneously.

Abstract: A method of controlling a wire-cut electric discharge machine to prevent cutting errors when cutting a corner CN which are caused by flexing of a wire electrode 1 during electric discharge cutting of a workpiece. Electric discharge is stopped when a rectilinear slot is cut to measure an amount of flexing of the wire electrode 1, and then the measured amount of flexing is used to effect an arithmetic operation to calculate a commanded speed or an interval of time in which relative movement between the wire electrode and the workpiece is arrested at the corner CN. The corner CN is cut under the control of the calculated commanded speed or interval of time in which the relative movement is arrested.

Abstract: A cutting control method for reducing cutting errors at a corner due to flexing of a wire electrode in a wire-cut electric discharge machine in which a voltage is applied between the wire electrode and a workpiece to cut the latter with electric discharge energy while moving the workpiece relatively to the wire electrode based on cutting command data for cutting the workpiece to a predetermined shape. An amount of override (K) is determined by an override arithmetic unit (103b) using data (r) on the radius of curvature of a corner angle (.theta.) data which are given as the cutting command data from a paper tape (101). A relative speed (F) is derived by a relative speed arithmetic unit (103f) from the amount of override (K) and a commanded feeding speed (F.sub.0). Motors (MX, MY) are rotated by pulse distributors (105X, 105Y) and servo circuits (SVX, SVY), respectively, based on the relative speed (F) which is lower than the commanded feeding speed (F.sub.

Abstract: There is disclosed a method of controlling a wire-cut electric discharge machine to correct cutting errors due to flexing of a wire electrode caused by electric discharge. A processing unit processes data (x.sub.1, y.sub.1, r.sub.1, x.sub.2, y.sub.2) on a corner shape which is given by a paper tape and data on an amount of flexing (D.sub.0) upon rectilinear cutting for calculating a corrected radius of curvature r.sub.1 ' of the corner, and determines the center Pc of an arc having the radius of curvature r.sub.1 ' and contacting straight lines (l.sub.1, l.sub.2) and points of contact Pt, Pt' to move the wire electrode along a straight line P.sub.1 Pt, an arc PtPt', and a straight line Pt'P.sub.3 to thereby correct the cutting error at the corner.

Abstract: In an apparatus for processing a broken wire electrode in a wire-cut electric discharge machine for cutting a workpiece into a desired contour by electric discharge machining while the workpiece is transported relative to a wire electrode on the basis of machining command data, there is disclosed an apparatus for processing a broken wire electrode including a memory (CPX, CPY) for storing the position at which the wire electrode broke, an operator's panel with jog buttons (PJX, MJX, PJY, MJY) for generating a movement command following wire breakage to retract the workpiece from the wire breakage position (Xc, Yc), motors and drive circuitry (PD, SX, SY, MX, MY) for transporting the workpiece to a predetermined position on the basis of command, and a fitted point return button (Br) on the operator's panel for generating a signal to position the workpiece at the wire breakage position after the wire electrode is rethreaded in a wire transfer system.

Abstract: A system for restoring a numerically controlled machine tool to its former condition after a power interruption, the numerical control system being of the type in which a position sensor senses the current position of a movable member or of a drive motor of the machine tool and generates a current position signal in accordance with said current position, the movable member being positioned on the basis of a commanded position signal and the current position signal. The positional control information which prevails immediately prior to an interruption in the electric power which is applied to the machine tool and to the numerical control device is stored in a non-volatile memory before the power interruption occurs.

Abstract: A wire-cut electric discharge machining control method which enables the corner portion at the intersection of first and second tapered surfaces of a workpiece to be cut into a tapered surface of oblique cylindrical shape. With the present invention, the tapered surface of oblique cylindrical shape is formed between the first and second tapered surfaces by entering command data for the radius r of the oblique cylindrical tapered surface in addition to positional control information for cutting the first and second tapered surfaces, computing a pair of points Q and R where the oblique cylindrical tapered surface meets the first and second tapered surfaces from the positional control information and radius, and cutting the tapered surface of oblique cylindrical shape between the points Q and R.

Abstract: A wire or band electrode type electric discharge machine for machining hard metals by an electric spark generated between the metal workpiece and a wire electrode which is fed longitudinally to provide a fresh supply thereof while a prescribed relative motion is established between the workpiece and the wire electrode. The invention provides a clamping mechanism on the wire supply side of the workpiece for clamping the wire electrode if it breaks during operation, and a wire electrode feed mechanism for automatically guiding the broken end of the wire through the opening that has been machined in the workpiece. A wire electrode pull-up mechanism is provided on the other side of the workpiece for gripping and pulling up the wire electrode. If the electrode wire breaks during a machining operation, the clamping mechanism immediately clamps the wire electrode and prevents it from falling under its own weight.

Abstract: A method and apparatus for restoring a broken wire electrode in a wire electrode-type electric discharge machine for machining a workpiece into a desired shape while the workpiece is moved relative to the wire electrode on the basis of machining command data. For effecting the restoration of the wire electrode, memory means are provided for storing the relative machining starting position of the workpiece and the wire electrode at the machining starting point, and the relative wire electrode breakage position of the workpiece and the wire electrode when the wire electrode breaks. After the wire electrode breaks the relative position of the workpiece and the wire electrode is brought into coincidence with the machining starting position on the basis of information indicative of the machining starting position and the wire electrode breakage position.

Abstract: A numerically controlled wire-cutting electric discharge machine composed of a numerical control apparatus controlling a feeding of a piece of work on at least three axes and a wire-cutting electric discharge apparatus. The wire-cutting discharge apparatus comprises a pair of V type slot guides which stretch a wire therebetween, a first and a second drive means which displace the work in the direction of two axes with respect to the wire electrode and a third drive means which rotates at least one of the V type slot guides around a predetermined axis, so that the relative displacement between the piece of work and the wire electrode is controlled via the first and second drive means by two outputs of the numerical control apparatus, the V type slot guide is rotated via the third drive means by another output of the numerical control apparatus so that the V type slot guide is turned a predetermined angle in the direction of the above-mentioned relative displacement.

Abstract: This disclosure relates to an improved electro-hydraulic pulse motor wherein safety valves are arranged in hydraulic circuits provided for the hydraulic motor part of an electro-hydraulic pulse motor so as to release abnormal high pressure produced in the circuits due to sudden interruption of the operation of an electric pulse motor part of the electro-hydraulic pulse motor. As a result, breakage of the circuits or four way pilot valve part of the electro-hydraulic pulse motor can be avoided.