A wire electrical discharge machine includes: a gap voltage detector for detecting a voltage across an electrode gap; a first voltage control unit for applying a first voltage to the electrode gap; a discharge determiner for determining whether or not the electrode gap is in a discharging state during application of the first voltage; and a second voltage control unit for supplying a machining current through the electrode gap when the electrode gap is in a discharging state. After a supply of the machining current to the electrode gap, even when a discharge is induced by the next application of the first voltage to the electrode gap, the second voltage control unit prohibits application of a second voltage to the electrode gap.

A wire electrical discharge machine includes: a gap voltage detector for detecting a voltage across an electrode gap; a first voltage control unit for applying a first voltage to the electrode gap; a discharge determiner for determining whether or not the electrode gap is in a discharging state during application of the first voltage; and a second voltage control unit for supplying a machining current through the electrode gap when the electrode gap is in a discharging state. After a supply of the machining current to the electrode gap, even when a discharge is induced by the next application of the first voltage to the electrode gap, the second voltage control unit prohibits application of a second voltage to the electrode gap.

A method and device for electrical discharge machining (EDM) a workpiece by means of a train of machining pulses. During the machining time the machining pulses are applied to the working gap between workpiece and electrode. An open voltage is first applied, and it is increased to a second open voltage level if a discharge does not occur within a waiting time d.sub.0, and further increased to a third open voltage level if a discharge does not occur within a second waiting time d.sub.1.

An average product of the actual open voltages times the partial ignition delays is computed and subtracted from the product of a reference open voltage times the total ignition delay, and the servo setpoint value is adjusted accordingly. The actual axes positions are sampled in real time and the discharge electrical parameters are adjusted accordingly. The discharge electrical parameters can be adjusted according to the duration of d0 and d1.

A method and device for electrical discharge machining (EDM) a workpiece by means of a train of machining pulses. During the machining time the machining pulses are applied to the working gap between workpiece and electrode. An open voltage is first applied, and it is increased to a second open voltage level if a discharge does not occur within a waiting time d.sub.0, and further increased to a third open voltage level if a discharge does not occur within a second waiting time d.sub.1.

An average product of the actual open voltages times the partial ignition delays is computed and subtracted from the product of a reference open voltage times the total ignition delay, and the servo setpoint value is adjusted accordingly. The actual axes positions are sampled in real time and the discharge electrical parameters are adjusted accordingly. The discharge electrical parameters can be adjusted according to the duration of d0 and d1.

A method for preprocessing data related to a tool electrode, which is applied in an EDM machine to manufacture a part comprises: generating an electrode model for the tool electrode based on the geometry of the part; generating the cavity shape model (volume of the part to erode), combining the electrode and cavity shape model, dividing the resulting model into a plurality of slices in a plurality of parallel planes, wherein at least one slice is composed of at least two sections, which are topologically disconnected; and generating for each slice a slice-geometry data, and generating an electrode-geometry data including the slice-geometry data.

A method for preprocessing data related to a tool electrode, which is applied in an EDM machine to manufacture a part comprises: generating an electrode model for the tool electrode based on the geometry of the part; generating the cavity shape model (volume of the part to erode), combining the electrode and cavity shape model, dividing the resulting model into a plurality of slices in a plurality of parallel planes, wherein at least one slice is composed of at least two sections, which are topologically disconnected; and generating for each slice a slice-geometry data, and generating an electrode-geometry data including the slice-geometry data.

There is provided a wire electrical discharge machine that includes a temperature detection unit, an actual position correction amount calculation unit, a correction amount calculation unit, a correction amount adjustment unit, a position correction amount adjustment unit, and a corrective movement amount calculation unit. The actual position correction amount calculation unit calculates an actual position correction amount for an upper/lower guide section in accordance with reference position coordinates at a reference temperature and with actual position coordinates at a temperature different from the reference temperature. The correction amount calculation unit uses a prepared correction amount arithmetic expression. The correction amount adjustment unit calculates a correction amount adjustment value from the actual position correction amount and the position correction amount.

There is provided a wire electrical discharge machine that includes a temperature detection unit, an actual position correction amount calculation unit, a correction amount calculation unit, a correction amount adjustment unit, a position correction amount adjustment unit, and a corrective movement amount calculation unit. The actual position correction amount calculation unit calculates an actual position correction amount for an upper/lower guide section in accordance with reference position coordinates at a reference temperature and with actual position coordinates at a temperature different from the reference temperature. The correction amount calculation unit uses a prepared correction amount arithmetic expression. The correction amount adjustment unit calculates a correction amount adjustment value from the actual position correction amount and the position correction amount.

The invention relates to a method for electrical discharge machining of workpieces by electrical discharge pulses generated by a power module of an electrical discharge machine. The invention is characterized in that firstly the discharge voltage of a number N1 of electrical discharge pulses is acquired and stored, secondly a front discharge voltage (63) is determined out of this amount of N1 acquired discharge voltages and thirdly, the voltage Uhps (64) of the electrical discharge pulses produced by the power module for machining the workpiece (17) is adjusted in function of the determined front discharge voltage (63).

A method of controlling a working gap between one or more cathodic tools and an anodic workpiece in an electrochemical material dissolution process, the method comprising: providing a cathodic tool and an anodic workpiece defining a working gap therebetween, the cathodic tool and the workpiece being at least partially immersed in a conductive electrolyte solution; providing a negative electrical potential to the cathodic tool; monitoring one or more of the electrical potential, current, current density and charge between the cathodic tool and the anode to determine the working gap between the cathodic tool and the anode; and, controlling one or more process parameters to maintain one or more of the working gap and electrochemical working conditions between the cathodic tool and anodic workpiece at a targeted value.