Abstract: The electric power unit for machining of a wire electric discharge machine includes an electric discharge state discriminate or (1a) for discriminating a state of electric discharge generated between the electrodes and an impression voltage selecting means (1b) for inverting the polarity of the electric discharge inductive pulse voltage from the previous electric discharge inductive pulse voltage when an electric discharge state between the electrodes is discriminated to be abnormal (Y1) or open (Y3) and for making the polarity of the electric discharge inductive pulse voltage to be the same as the polarity of the previous electric discharge inductive pulse voltage when the electric discharge state between the electrodes is discriminated to be normal (Y2).

Abstract: A machining-fluid ejection device for a wire electric discharge machining apparatus includes a nozzle for ejecting machining-fluid into an inter-electrode gap between a workpiece (W) and a wire electrode (E), a casing (16) fixed to a machining head (15) disposed above or below the workpiece (W), a coupling member (18) for coupling the casing (16) and a nozzle (17), having a predetermined elastic coefficient, and deforming according to the machining-fluid pressure; an assemblage of the coupling member (18) and the nozzle (17) has hollow portions, formed with an inlet side internal diameter (D2) and an outlet side internal diameter (D1) on a machining-fluid inlet side and outlet side respectively, whose sectional areas do not change, and a hollow portion, formed with a minimum internal diameter (D0) between the machining-fluid inlet side and the outlet side, whose sectional area does not change. Machining productivity may be raised for nozzle contact machining and nozzle separation machining.

Abstract: An electric discharge machine for machining a workpiece (2a) made of insulating material or other materials comprises: a first comparison member (17) for comparing voltage (V) between the electrodes of the electrode (1) and the workpiece (2a) with the first reference voltage (V1) which is set at a value close to electric power source voltage (V0) not higher than electric power source voltage (V0); a second comparison member (18) for comparing voltage (V) between the electrodes with the second reference voltage (V2) which is set at a value lower than the first reference voltage (V1); and a control member (19) for setting a short electric discharge pulse width (TP1) in the case where voltage (V) between the electrodes is lower than the second reference voltage (V2) according to the result of comparison conducted by the second comparison member (18) at a point of time when a predetermined period of time (T0) has passed from the time when voltage (V) between the electrodes becomes lower than the first reference v

Abstract: An electric power unit for machining of a wire electric discharge machine for machining a workpiece (W) in which an electric discharge inductive pulse voltage is impressed upon between electrodes of a wire electrode (E) and workpiece (W), after insulation between the electrodes has been broken by the pulse voltage and electric discharge has been induced, a pulse voltage for machining is impressed upon between the electrodes so as to conduct machining on the workpiece (W).

Abstract: An electric discharge machine for machining a workpiece (2a) made of insulating material or other materials comprises: a first comparison member (17) for comparing voltage (V) between the electrodes of the electrode (1) and the workpiece (2a) with the first reference voltage (V1) which is set at a value close to electric power source voltage (V0) not higher than electric power source voltage (V0); a second comparison member (18) for comparing voltage (V) between the electrodes with the second reference voltage (V2) which is set at a value lower than the first reference voltage (V1); and a control member (19) for setting a short electric discharge pulse width (TP1) in the case where voltage (V) between the electrodes is lower than the second reference voltage (V2) according to the result of comparison conducted by the second comparison member (18) at a point of time when a predetermined period of time (T0) has passed from the time when voltage (V) between the electrodes becomes lower than the first reference v

Abstract: A machining-fluid ejection device for a wire electric discharge machining apparatus includes a nozzle for ejecting machining-fluid into an inter-electrode gap between a workpiece (W) and a wire electrode (E), a casing (16) fixed to a machining head (15) disposed above or below the workpiece (W), a coupling member (18) for coupling the casing (16) and a nozzle (17), having a predetermined elastic coefficient, and deforming according to the machining-fluid pressure; wherein an assemblage of the coupling member (18) and the nozzle (17) has hollow portions, formed with an inlet side internal diameter (D2) and an outlet side internal diameter (D1) on a machining-fluid inlet side and outlet side respectively, whose sectional areas do not change, and a hollow portion, formed with a minimum internal diameter (D0) between the machining-fluid inlet side and the outlet side, whose sectional area does not change. Machining productivity may-be raised for nozzle contact machining and nozzle separation machining.

Abstract: An automatic wire feeder of a wire electric discharge machine includes an optical sensor for detecting positional information of a wire electrode in an inserting passage between a feed roller for feeding a wire electrode and an upper wire guide; and a control unit for discriminating a state of vibration or deflection of the wire electrode according to the positional information detected by the optical sensor and also for controlling a feeding and rewinding motion of the feed roller according to a quantity of deflection of the wire electrode. Due to the foregoing, buckling caused by an inserting load in the process of automatic wire connection can be positively detected, and the reliability can be enhanced and further the repetition of connecting the wire again can be reduced.

Abstract: A wire electrical discharge machine includes a wire bobbin 3 with a wire electrode 1 wound therearound; a fixing base 25 for fixing the wire bobbin 3 so that the wire bobbin 3 does not rotate; a guide pulley 23 for supporting the wire electrode 1; a rotating arm 21 for supporting the guide pulley 23 and for pulling out the wire electrode 1 from the wire bobbin 3 and rotating the wire electrode 1 about the wire bobbin 3; a sliding mechanism 24 for supporting the guide pulley 23 slidably with respect to the rotating arm 21, in correspondence with a winding position of the wire electrode 1 on the wire bobbin 3; and a braking motor 13 for driving the rotating arm 21. It is possible to disperse the wear of the wire electrode 1 and improve the machining rate and machining accuracy. Further, it is possible to improve the reliability and suppress an increase in cost.

Abstract: An electric discharge machine for machining a workpiece by an electric discharge by supplying a machining fluid to a gap between an electrode and the workpiece and supplying pulses to the workpiece while providing the electrode with a jump motion, the jump motion being a periodic motion of the electrode relative to the workpiece; wherein the electric discharge machine detects a state quantity caused in a main body of the electric discharge machine by a reactive force produced by a machining operation in the gap between the electrode and the workpiece and changes machining conditions of the workpiece in accordance with a detected value of the state quantity.

Abstract: A wire electrical discharge machining apparatus provided with: a nozzle for spraying and supplying machining liquid, the nozzle being supported so that a state of the nozzle is switched over from a contact state with a work piece to a non-contact state with the work piece, and vice versa; a spring acting on the nozzle in a direction to make the nozzle move away from the work piece; a pump for changing and controlling a hydraulic pressure of the machining liquid; and electrical conduction switch-over apparatus by which power supply to the work piece is switched over from the nozzle of a conductor to apparatus other than the nozzle, and vice versa, such that the hydraulic pressure of the machining liquid during electric discharge machining is changed and controlled by the pump so that the state of the nozzle is switched over from the contact state to the non-contact state.

Abstract: An automatic wire feeder of a wire electric discharge machine comprises: an optical sensor for detecting positional information of a wire electrode in an inserting passage between a feed roller for feeding a wire electrode and an upper wire guide; and a control unit for discriminating a state of vibration or deflection of the wire electrode according to the positional information detected by the optical sensor and also for controlling a feeding and rewinding motion of the feed roller according to a quantity of deflection of the wire electrode. Due to the foregoing, buckling caused by an inserting load in the process of automatic wire connection can be positively detected, and the reliability can be enhanced and further the repetition of connecting the wire again can be reduced.

Abstract: An electric discharge machine for machining a workpiece by an electric discharge by supplying a machining fluid to a gap between an electrode and the workpiece and supplying pulses to the workpiece while providing the electrode with a jump motion having a periodic motion of the electrode relative to the workpiece; wherein the electric discharge machine detects a state quantity caused in a main body of the electric discharge machine by a reactive force produced by a machining operation in the gap between the electrode and the workpiece and changes machining conditions of the workpiece in accordance with a detected value of the state quantity.

Abstract: A surface treating is performed by an electric discharge. The electric discharge is generated by applying a voltage between an electrode and a metal workpiece. The electrode is a solid or green compact electrode or the like which is made of a reforming material. The workpiece may be an end mill or the like. Then, a coating layer is formed on a surface of the metal workpiece. Thereafter, a nitriding treatment is performed on the coating layer in a nitriding vessel or the like. Thus, a hard coating layer of better quality is formed on the surface of the workpiece whether a material of the workpiece is steel or hard metal.

Abstract: In machining, a short-circuit determination reference time stored in a parameter memory is changed by a short-circuit determination reference time changing device in response to rpm or a rotational speed of a rotating electrode, duration of a short-circuit detected between the electrodes is measured by a short-circuit duration time determining device, and a short-circuit evading operation is executed by a short-circuit back control device in a case where the duration of a short-circuit has surpassed the short-circuit determination reference time.

Abstract: An electric discharge machine for machining a workpiece by an electric discharge by supplying a machining fluid to a gap between an electrode and the workpiece and supplying pulses to the workpiece while providing the electrode with a jump motion, said jump motion being a periodic motion of the electrode relative to the workpiece; wherein said electric discharge machine detects a state quantity caused in a main body of the electric discharge machine by a reactive force produced by a machining operation in the gap between the electrode and the workpiece and changes machining conditions of the workpiece in accordance with a detected value of the state quantity.

Abstract: To obtain high machining speed and machining accuracy in three-dimensional machining by using of an electrode of simple shape. Applying voltage between an electrode of simple shape and a workpiece, performing three-dimensional control by an NC control while synthesizing a feed of a Z-axis direction for correcting longitudinal consumed amount of an electrode with an X-Y plane feed, storing amount equivalent to an X-Y moving distance in an X-Y plane corresponding to correcting moving amount of the Z-axis direction in an electrical discharge machining method for machining a desired three-dimensional shape and performing a feed of correcting moving amount in the Z-axis direction each time a moving distance in the X-Y plane on a moving locus during machining reaches the above stored amount.

Abstract: A surface treating method uses an electric discharge machining to form a coating layer having strong adhesion and excellent characteristics on a metal surface such as a hard metal. A discharge electrode is formed by powders containing metal hydride. Electric discharge is generated in a working fluid containing carbon between the discharge electrode and a workpiece. Thus, a coating layer of the metal hydride is formed on a surface of the workpiece.

Abstract: An electric discharge machining apparatus and method are provided first having a data storage for storing initial machining conditions such as a two-dimensional outline path for a machined form, dimensions of the machined form, a feed rate in the axial direction of an electrode for a given movement of the tool electrode in the horizontal direction, and an interval period of inline measurement. In addition, the apparatus measures a machining depth at each interval period of inline measurement. The apparatus also computes machining parameters such as a machining depth for each machining pass, a number of remaining passes of machining which are to be executed, and also increments an outline offset according to the measured machining depth. An electrode position control then provides positional control of a tool electrode according to the computed machining parameters.

Abstract: An electric discharge machining apparatus in which at least either of a tool electrode or a workpiece is made of an anisotropic conductive material, includes, on a good conductive surface 20b of the anisotropic conductive material 2, a portion for connecting an isotropic conductive member 22. Electric discharge is generated on the good conductive surface 20b of the anisotropic conductive material 2. A conductive adhesive agent 23 is employed to bond the anisotropic conductive material 2 and the isotropic conductive member 22 to each other. The anisotropic conductive material is a pyrocarbon material. The pyrocarbon heat resolved carbon material is employed as a tool electrode material. Incombustible dielectric fluid, such as pure water, is employed as dielectric fluid.

Abstract: A surface treating apparatus rotates a rotating tool and moves a surface treating electrode relative to the tool via a rotating shaft driver and a Z-axis driver. A power source applies voltage to generate an electric discharge between the tool and the electrode, thereby forming a reforming layer on a peripheral flank and a rake face of the tool.