摘要:
An electric discharge machining apparatus including a first power source for applying machining voltage to a machining gap to generate an electric discharge, a second power source for applying voltage of equal to or lower than 20 V to the machining gap, a transistor switching bridge connected to both the workpiece and the tool electrode, a switch for selectively connecting one of the first and second power sources to the transistor switching bridge, a transistor controller for controlling on/off switching operation of the transistor switching bridge to alternatively change polarity of voltage being applied to the machining gap, a contact detector for electrically detecting the contact between the workpiece and the tool electrode when output of the second power source is applied across the machining gap, and an NC device which controls the switch so that the first power source is connected to the transistor switching bridge when the application of the machining power is required while the second power source is connected to the transistor switching bridge when detecting the contact by the contact detector is required.
摘要:
Disclosed is a radio apparatus in which modulating signals (I, Q signals) from an arithmetic/control unit are converted to analog signals, which are then applied to an orthogonal modulator. A modulated wave for transmission, which has been produced by orthogonally modulating a reference carrier wave by the modulating signals, is demodulated by the orthogonal detector. The arithmetic/control unit compares the modulating signals and the demodulated signals and, based upon the comparison, updates distortion compensation coefficients and applies pre-distortion processing to the modulating signal using the distortion compensation coefficients. Leakage carrier produced due to offset of the orthogonal modulator is detected and the arithmetic/control unit adjusts the level of the modulating signals or shifts the phase of the reference carrier wave in such a manner that the leakage carrier (offset) becomes zero.
摘要:
A wire cut electric discharge machine including a device (6) for pulling a wire electrode (1) such that it travels along a wire transport path, a servo motor (4B) which applies tension to the traveling wire electrode, an NC device which generates a signal indicating a tension setting value; a tension detector (9) which detects the tension applied to the wire electrode and generates a signal indicating the detected value, and a tension control device which processes the signal indicating the tension setting value and the signal indicating the tension detection value, and commands the servo motor rotational speed. The tension control device includes a non-essential frequencies setting circuit (20) which sets non-essential frequencies and generates a signal indicating that setting value, and an electric filter device (19), which blocks non-essential frequencies based on the non-essential frequencies setting circuit output signal.
摘要:
An electrical discharge detector (30) which detects electrical discharge generated at a machining gap; a pulse generator (41) which generates a pulse signal which stops after the commencement of electrical discharge in response to the electrical discharge detector; first switching circuits (22A, 22D) which apply voltage pulses of one polarity in response to the pulse signal; second switching circuits (22B, 22C), which apply voltage pulses of the opposite polarity to the machining gap in response to the pulse signal; a flip-flop (46) which retains one of two states; a gate circuit (42, 43) which supplies a pulse signal to the first switching circuit when one state is retained in the flip-flop, and supplies a pulse signal to the second switching circuit when the other state is retained in the flip-flop; circuits (CK, 48, 49) which supply a high frequency pulse to the flip-flop for the duration of the pulse signal; a circuit (44) which supplies a single pulse to the flip-flop each time the pulse signal is inactive; and a machining current supply circuit (10), which supplies a machining current to the machining gap after the commencement of electrical discharge.
摘要:
A contact position measurement method including moving either a wire-shaped tool electrode or a workpiece relative to the other within a plane, and causing the wire to approach a reference position on the workpiece; applying a voltage between the wire and the workpiece with the wire oriented perpendicular to the plane; detecting contact between the workpiece reference position and the wire; placing the workpiece reference position generally at the center of vibration of the wire, determined in accordance with the number of occurrences of detected contact; generating coordinate data indicating the position of the wire with respect to the workpiece; and determining the position of contact based on the coordinate data.
摘要:
A power supply for an electroerosion machine having a switching element which controls the machining current in the gap. The value of the current is compared with a predetermined voltage and the signal generated based on this comparation is provided to a logic gate, advantageously an "AND" gate, whose output signal is applied to the control electrode of the switching element. The power supply surpresses any arcing tendency during gap short circuit conditions and increases the total current through the gap even when gap voltage is low in order to maintain a high machining rate. Electrode consumption is reduced by using a generally step-type current waveform signal. Machining current during the discharge period may be controlled to more closely approximate a square wave so that shifting to a faster machining rate can be easily accomplished by accepting some sacrifice in electrode consuption. Preferably, two or more switching and gating devices are used to permit gap current to flow intermittently during the entire discharge period.