摘要:
The invention provides a method for determining a condition of a wire electrode deployed in a wire electrical discharge machine, the wire electrical discharge machine comprising a wire traveling circuit with a first- and a second wire guiding head by which the wire electrode is guided and positioned in relation to a workpiece laying between these wire guiding heads. The wire electrode is in contact with a first- and a second electrical contact, both contacts being located on the wire traveling circuit. The first- and the second electrical contact and a wire electrode segment L of said wire electrode lay after the workpiece processing section in wire traveling direction. An electrical impedance ZL of the wire electrode segment L between the first- and the second electrical contact is measured, and the condition of the wire electrode is derived from the measured electrical impedance ZL of said wire electrode segment L.
摘要:
The invention relates to a method and device for electrical Wire electrical discharge machining method (WEDM) for forming a desired pattern on a workpiece by a WEDM machine tool, in which a preliminary voltage pulse is applied to a gap between a wire electrode and a workpiece, and in which, at the breakdown of said preliminary voltage pulse, a first machining discharge pulse is applied to the wire electrode. A discharge position of said first machining discharge pulse along the engagement line of the wire electrode and the workpiece is determined in real time based on the voltage signals and/or current signals generated by said first machining discharge pulse,and that at least one additional machining discharge pulse is selectively applied directly after the first machining discharge pulse, in which said selective application of the additional machining discharge pulse is based on the determined discharge position and based on a digital pattern representing the desired pattern.
摘要:
The invention relates to 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 do, and further increased to a third open voltage level if a discharge does not occur within a second waiting time d 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. Moreover, a micro oscillation can be imposed to the axes.
摘要:
The present invention is related to a method for determining a condition of a wire electrode deployed in a fastwire cutting machine. The fastwire cutting machine comprises a wire traveling circuit in which the wire travels back and forth, with a first- and a second wire guiding head by which the wire electrode is guided and positioned in relation to a workpiece laying between these wire guiding heads. The wire electrode is in contact with a first- and a second electrical contact, both contacts being located on the wire traveling circuit, and that a value reflecting an electrical impedance ZL of the wire electrode segment L between the first electrical contact and the second electrical contact is measured. The measurement of said wire electrode segment L is conducted in a dry state, and that the condition of the wire electrode is derived from the measured value reflecting the electrical impedance ZL of said wire electrode segment L.
摘要:
The invention relates to a method for the machining of workpieces (11) and inspection of the processed workpiece surface in a machine tool (1), preferably a die sinking electrical discharge machine. The method comprising at least one machining process interruption during which the processed surface of the workpiece (11) is inspected. Within said machining process interruption, at least one image of the processed workpiece surface is captured on the machine tool (1) by means of a digital camera (12). The images are processed by one or two pattern recognition algorithm (PRA D, PRA S), which were previously trained to determine the surface characteristics such as roughness parameters, functional surface features and/or characteristic defects of the processed workpiece surface captured on that at least one image. The determined surface characteristics are used to resume the processing of the workpiece surface with or without adjusting the processing parameters. The invention includes an accordingly functioning machine tool (1).
摘要:
The invention relates to a method 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, the ignition delay time td is measured, then, at the beginning of the discharge, its fall time tf is measured, and certain shape features (e.g. the pedestal and ramp) of the pulse are adapted in real time for the very same discharge, as a function of said ignition delay time and/or fall time. Moreover, instead of shaping the very same discharge, one or more subsequent discharges can be shaped as a function of td and/or tf of a single discharge, or of an average of td and/or tf over several discharges.
摘要:
The invention relates to a method and device for wire electrical discharge machining (WEDM), in which a first voltage UCH1 is measured between a first current feeder and the workpiece, and a second voltage U CH2 is measured between a second current feeder the workpiece, whereas said first- and second voltage U CH1 , U CH2 are measured when current of the machining discharge pulse is zero, for instance at the end of the of the machining discharge current pulse, and a voltage difference of said measured voltages ΔU CH = U CH1 - U CH2 is determined, and a discharge position of said machining discharge pulse is determined in real time, as a function of said voltage difference ΔU CH .