Fanuc Corporation

Clarion Co

Institute of Technology Precision Electrical Discharge Work's

Canon Kabushiki Kaisha

Masaki Kurihara

Masao Kamiguchi

Yojiro Matsuda

Kaoru Hiraga

Akiyoshi Kawahara

Hiroaki Naruse

Shoji Futamura

Akihiro Sakurai

Daisuke Shimoyama

Masao Murai

Kaoru Room 10-106 Fanuc Manshonharimomi Hiraga

A controller for a wire electric discharge machine which can achieve stable machining with high surface accuracy without requiring adjustment of a gain or the like in wire-electrode feed control. A discharge gap detection unit detects a voltage between a wire electrode and a workpiece. An amount-of-machining-per-unit-distance change detection unit obtains an average machining voltage, and a voltage drop Ethat is a difference between the obtained average machining voltage and a no-load voltage. A comparative determination unit obtains a ratio E/Ebetween a reference voltage drop Estored in a reference-amount-of-machining-per-unit-distance relative value storage unit and the drop voltage E. A feed pulse arithmetic unit obtains a feed speed that makes the amount of machining per unit time constant, on the basis of the ratio E/Eand a predetermined feed speed, and distributes feed pulses to motors to thereby move the wire electrode relatively to the workpiece. Since the amount of machining per unit time is kept constant, the surface accuracy in finishing is high and stable machining can be performed.

Controller for wire electric discharge machine

A discharge pulse number generated between a wire electrode and a workpiece is counted every predetermined time. A ratio Px/Ps of this counted value Px to the reference pulse number Ps will be determined to control an amount of coolant in response to this ratio Px/Ps. Also, in response to this ratio Px/Ps, an amount of movement within predetermined time is controlled. Further, through the ratio Px/Ps and the like, quiescent time to be controlled by the detection voltage generator is controlled. Thereby, surplus supply of energy is prevented, the machining speed and machining precision is improved and any disconnection of the wire electrode is avoided.

A controller of a wire electric discharge machine monitoring a change in thickness of a workpiece and a current density in real time, promoting a machining speed by preventing occurrence of disconnection of a wire electrode even when the change in the thickness is caused in the workpiece and improving a dispersion in a machining enlargement amount. A machining distance calculating device outputs a signal at each progress of machining by a predetermined distance &Dgr;x. A main pulse number storing device counts a main pulse number for discharge machining outputted from a main pulse generator during a time period of the signal. A thickness calculating device calculates the thickness from a reference main pulse number in machining a reference thickness, the main pulse number stored to the main pulse number storing device and the reference thickness at each reception of the signal. The calculated thickness, further, a machining current, the machining speed and a machining current density are displayed. A discharge pause time control device changes a pause time period of voltage applied to the wire electrode and the workpiece in accordance with a thickness change rate and adjusts the machining current density such that no change is caused before and after the change in the thickness.

Controller of wire electric discharge machine

Electric discharge machining power source unit for electric discharge

A discharge machining apparatus adapted to permit the supply of discharge current to be cut off without increasing electrode consumption. Arrangements are made to gradually increase the level of discharge current, rather than maintaining the current level of discharge pulse. By doing so, electrode consumption becomes independent of the pulse width of the discharge pulse, so the discharge current can be cut off immediately after an abnormal state such as short circuiting or an instantaneous interruption of the discharge current occurs, eliminating the danger of deteriorating the quality of the machining surface of a workpiece.

Electrical discharge machining apparatus with discharge current control

The direction-variable speaker system has first and second speaker cases containing speaker units for different reproduction bands, respectively, and an intermediate case interposed between those two speaker cases. The first speaker case and the intermediate case are connected by a first pivotal shaft pivotally of each other and are given tendency to pull each other. Between the first speaker system and the intermediate case is provided a rising angle setting mechanism including a first gear cam secured to one of these cases and a stopper member secured to the other for meshing engagement with the first gear cam. The second speaker case and the intermediate case are connected by second pivotal shaft pivotally of each other and are given tendency to pull each other. Between the intermediate case and the second speaker case is provided a twisting angle setting mechanism including second gear cam secured to the second speaker case concentrically of the second pivotal shaft and third gear cam secured to the intermediate case for meshing engagement with the second gear cam.

Direction-variable speaker system

Growing community of inventors

Tokyo, Japan

Masaki Kurihara