A wire electrical discharge machine includes: a supporting member for relatively moving a wire electrode relative to a measurement target; servomotors for moving the supporting member; a setting changer for changing the setting of a directive speed; and a motor controller that controls the servomotors in performing move-and-contact detection for detecting contact between the wire electrode and the measurement target by moving the two relative to each other, so that the wire electrode is moved relative to the measurement target based on the directive speed changed and specified by the setting changer.

A wire electrical discharge machine includes a first voltage applying circuit, a second voltage applying circuit, and a switch controller. The first voltage applying circuit includes a first DC power source for applying a positive polarity voltage across an electrode gap, and a first switch for on/off-switching of application of the positive polarity voltage. The second voltage applying circuit includes a second DC power source for applying a reverse polarity voltage to the electrode gap, and a second switch for on/off-switching of application of the reverse polarity voltage. The switch controller controls the first switch and the second switch so that the first switch and the second switch are not turned on simultaneously. The first DC power source and the second DC power source are set up so that the absolute value of the reverse polarity voltage is lower than the absolute value of the positive polarity voltage.

A wire electric discharge machining apparatus includes a machining unit that forms a product part by cutting off an outer frame portion from a workpiece and a control device that controls the machining unit. The machining unit machines a first boundary region in a boundary between the outer frame portion and the product part to leave an uncut portion, cuts off the product part from the outer frame portion by machining a second boundary region, which is the uncut portion, and repeats machining for the first/second boundary regions. When n is a natural number equal to or larger than 2, the control device sets, based on a machining state when the first boundary region is machined, different machining conditions as first machining conditions in machining the first boundary region for n-th time and second machining conditions in machining the second boundary region for n-th time.

In a wire electric discharge machine, time from application of a voltage to a machining gap between a workpiece and a wire electrode until occurrence of electric discharge is measured as a discharge delay time, and the measured discharge delay time is integrated over a predetermined measurement period to calculate a discharge delay integrated time. Further, the number of times of the voltage application in the measurement period is counted. An average discharge delay time per voltage application in the measurement period is calculated from the discharge delay integrated time and the number of times of voltage application. The movement of the wire electrode with respect to the workpiece is controlled on the basis of the average discharge delay time.

In a wire electric discharge machine, time from application of a voltage to a machining gap between a workpiece and a wire electrode until occurrence of electric discharge is measured as a discharge delay time, and the measured discharge delay time is integrated over a predetermined measurement period to calculate a discharge delay integrated time. Further, the number of times of the voltage application in the measurement period is counted. An average discharge delay time per voltage application in the measurement period is calculated from the discharge delay integrated time and the number of times of voltage application. The movement of the wire electrode with respect to the workpiece is controlled on the basis of the average discharge delay time.

A portable movable discharge processing system by short electric arc, comprising a power supply cooling water tank (1), a short electric arc cutting power supply (2), a ring current device (16), a feeding mechanism (17), a hanging bracket and a pneumatic ring current tool (35) mounted on the hanging bracket, which are successively and cooperatively mounted on a horizontal plane; an air compressor (22) and a sewage pump (26), which are successively connected to the feeding mechanism; a self-priming pump (3) and a movable short-electric arc cutting device control cabinet (4), which are successively connected to the air compressor; an anode device (15) which is connected to the movable short-electric arc cutting device control cabinet (4) through an anode cable (6); a cathode device which is connected to the movable short-electric arc cutting device control cabinet (4) through a cathode cable (5); and a water pump which is connected to the anode device through a pipeline. The discharge processing system is convenient to use, low in labor intensity and good in safety.

The invention relates to a pulse generator module (50) for electric discharge machines which comprises a generator enclosure (51) containing printed circuit boards (PCBs), wherein at least one of the PCBs is a generator board (52). The PCBs (52) are all arranged in one plane.

A drive circuit configured to drive a load. The drive circuit comprises a transformer. The transformer comprises a transformer primary comprising one or more primary windings connected to arms that pass through a magnetic material. The transformer also comprises a transformer secondary comprising secondary windings connected to planar secondary conductors which pass through the inside of the arms. The drive circuit also comprises a voltage source configured to apply a voltage across the transformer primary.

A contact detection unit, after executing a first detection operation of contact between the wire electrode and the workpiece at a first relative movement speed and a first pulse cycle, executes a second detection operation of contact between the wire electrode and the workpiece, at a second relative movement speed which is slower than the first relative movement speed, and at a second pulse cycle which is longer than the first pulse cycle, and a movement speed control unit, after execution of the first detection operation, and prior to execution of the second detection operation, causes the wire electrode and the workpiece to relatively move in a distancing direction.

An electric discharge machining apparatus includes: electrodes the total quantity of which is equal to N; an alternating-current power source; and capacitors the total quantity of which is equal to N. The alternating-current power source applies an alternating voltage commonly to the electrodes. One end of each of the capacitors is connected to a corresponding one of the electrodes, whereas the other ends of the capacitors are commonly connected to the alternating-current power source.