A method for forming a heat exchanger plate includes: securing a wave form metallic sheet to a heat exchanger plate substrate, the substrate comprising a first face and a second face opposite the first face, the securing of the wave form metallic sheet being to the first face; and removing peaks of the sheet.

A wire electrical discharge machine to cut a workpiece by generating an electrical discharge in a dielectric working fluid between wire electrodes arranged in parallel and the workpiece includes: a work tank that stores the dielectric working fluid; a Z-axis stage that is disposed in a lower portion of the work tank and moves the workpiece in a Z-axis direction that is a vertical direction; a pillar that extends upward from the Z-axis stage and has an upper end portion located above the highest level of a fluid level of the dielectric working fluid in the work tank; an adjuster that is installed downward from a portion of the pillar located above the highest level of the fluid level, is disposed above the highest level of the fluid level, and adjusts the position or posture of the workpiece in a direction other than the vertical direction.

A wire electrical discharge machine for machining a workpiece by generating electric discharge at a discharge gap between the workpiece and a wire electrode includes: a machining current setting unit for setting the magnitude of a normal machining current depending on the discharge gap state at application of a discharge induction voltage at the previous time or previous times; and a machining current control unit configured to control a main discharge circuit so as to supply the normal machining current to the discharge gap when the present discharge gap state is the normal state, control the main discharge circuit so as to supply a short-circuit machining current smaller than a predetermined current to the gap when the discharge gap state is the short-circuited state, and control the main discharge circuit so as not to supply any machining current to the gap when the discharge gap state is the open state.

An electrical discharge machining (EDM) electrodes and associated methods are provided. An EDM electrode includes a holder rotatable about a rotation axis and a plurality of electrode elements attached to the holder and circumferentially arranged around the rotation axis. Respective positions of the electrode elements are radially adjustable relative to the rotation axis.

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.

The object of the present invention is to make it possible to maintain a stable electric discharge and to achieve a stable quality and machining performance even when a work having a non-uniform composition is machined.

A wire electric discharge machining device performs electric discharge machining on a work while controlling an inter-electrode distance between a wire and the work based on an inter-electrode voltage between the wire and the work so as to match a set target voltage. The wire electric discharge machining device includes an inter-electrode voltage measuring unit that measures the inter-electrode voltage, an actual amplitude calculating unit that calculates an amplitude of the measured inter-electrode voltage, and a target voltage correcting unit that corrects the target voltage in such a way that the calculated amplitude approaches the target amplitude that is set to a value larger than zero.

A method for forming a heat exchanger plate includes: securing a wave form metallic sheet to a heat exchanger plate substrate, the substrate comprising a first face and a second face opposite the first face, the securing of the wave form metallic sheet being to the first face; and removing peaks of the sheet.

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 electrical discharge machining (EDM) electrodes and associated methods are provided. An EDM electrode includes a holder rotatable about a rotation axis and a plurality of electrode elements attached to the holder and circumferentially arranged around the rotation axis. Respective positions of the electrode elements are radially adjustable relative to the rotation axis.

An electric discharge machining (EDM) system includes an electrode set having a plurality of electrodes. Each electrode is electrically-isolated from the other electrodes. The EDM system includes a power supply configured to generate an electric discharge between a workpiece and the electrode set to remove material from the workpiece. The power supply includes a multi-loop driver system and an AC-to-DC component that outputs DC electric power. The multi-loop driver system includes a plurality of power loop circuits coupled to an output of the AC-to-DC component. Each power loop circuit is electrically-isolated from other power loop circuits and is coupled to at least one electrode. The multi-loop driver system includes a drive controller coupled to the power loop circuits. The drive controller is configured to transmit at least one control signal to at least one power loop circuit to drive the AC-to-DC component to generate the electric discharge.