Abstract in simplified Chinese:用以由电腐蚀加工之设备包含一电极工具(EO)及一电极工作件(EP),构成一工作空隙(GA)之相对电极,及一电路具有双电压源(UD)连接至供应网络(A),安排产生腐蚀放电于电极工具(EO)及电极工作件(EP)之间。此双电压源(UD)包含一第一(U1)及一第二(U2)电压源由其电极相互电连接。此双电源(UD)由至少四各别分枝(B1至B4)连接至工作空隙,其至少之一包含一自电感组件(L1,LL)。开关设备(SW1,SW2)由选择连接该等分枝,可产生至少二增加电流斜坡及至少二降低电流斜坡。此等分枝经安排,俾未由腐蚀放电所消耗之多余之自电感能量回流至双电源(UD)。转移设备(PO)用作电流泵,以运行双电源(UD)之二电压源(U1,U2)间之能量转移。此设备如此可获得一电腐蚀产生器,适用于任何型式之电腐蚀,电流脉冲具有可进程之轮廓,此包含至少二不同之增加斜坡及二不同之降低斜坡。电源各可连接至供应网络(A)。电能量完全贡献于加工,大为节省能量。
Abstract in simplified Chinese:用以由电腐蚀加工之设备包含一电极工具(EO)及一电极工作件(EP),构成一工作空隙(GA)之相对电极,及一电路具有双电压源(UD)连接至供应网络(A),安排产生腐蚀放电于电极工具(EO)及电极工作件(EP)之间。此双电压源(UD)包含一第一(U1)及一第二(U2)电压源由其电极相互电连接。此双电源(UD)由至少四各别分枝(B1至B4)连接至工作空隙,其至少之一包含一自电感组件(L1,LL)。开关设备(SW1,SW2)由选择连接该等分枝,可产生至少二增加电流斜坡及至少二降低电流斜坡。此等分枝经安排,俾未由腐蚀放电所消耗之多余之自电感能量回流至双电源(UD)。转移设备(PO)用作电流泵,以运行双电源(UD)之二电压源(U1,U2)间之能量转移。此设备如此可获得一电腐蚀产生器,适用于任何型式之电腐蚀,电流脉冲具有可进程之轮廓,此包含至少二不同之增加斜坡及二不同之降低斜坡。电源各可连接至供应网络(A)。电能量完全贡献于加工,大为节省能量。
Abstract:
In the machining of a part (1) by electro-erosion using a wire-electrode (2), when the part has a positive polarity and the dielectric is water, the discharge generator (3) between the part (1) and the wire (2) generates an eddy current called "leak current" which induces on the surface of the part (1) a corrosion called "anodic dissolution". A secondary circuit maintained by a generator (5) between the part (1) and secondary electrodes (6) induces a compensation current, which is antagonist to the leak current, and weakens or eliminates the anodic dissolution of the part (1). Conveniently, the electrodes (6) are mounted on machining heads (7) with interposition of isolating material (8).
Abstract:
Tool-holder (5) which makes it possible to rotate a tool(1) at high speed around its axis of symmetry. Its tapered end (26) is engaged in the tapered bore (16) provided in the spindle (6) and is equipped with means of securing (14, 19) to the spindle (6) which exerts a clamping force suitable for fixing it rigidly by means of the spring (9) and which can thus rotate it at several thousand r.p.m. In a bore of suitable shape a clamp (2) is engaged, adapted to secure the electrode end (1) rigidly. An injection chamber (28) communicates with said bore and is connected by radial channels (27) to a fluid inlet. The clamp (2) has radial grooves to bring the cooling fluid (25) from the injection chamber (28) to the surface of the tool (1). An annular injector (50) holds the clamp by means of a nut (51); its wall facing the electrode-tool (1) is spaced at a distance (h) such that a film of liquid forms around the electrode (1). The spindle body (10) has a fixture (20, 21, 22) designed to connect it rigidly to the mobile element of a machining head or to an intermediary fixing element mounted on said mobile element. A sealed circuit (12, 13, 15) channels the liquid (25); it is connected by an input channel of small diameter which passes through the spindle body (10) to a liquid outlet in the mobile element of the machining head or in the intermediary fixing element mounted on said mobile element. An annular seal (14) of small diameter is mounted in the spindle body (10) around said channel (11'). Two carbon brushes (30) which supply electric current to the spindle / tool-holder / tool assembly are pressed against the channel (11') by springs (31). The motor (33) which rotates the spindle (6) around its axis of symmetry is mounted on the machining head and operates the gearwheel (41) by means of the belt (35). The connection element (36) is fitted with a claw system (37) which cooperates with corrresponding means (34) located under the motor (33).
Abstract:
Le dispositif d’usinage par électroérosion comprend une première source (U1) de tension/courant d’amorçage reliée à une électrode-outil (F) et une électrode-pièce (P) formant les pôles d’un gap d’usinage (G) et une seconde source (U2) de tension/courant qui peut être déconnectée grâce à deux interrupteurs (SW1, SW2). Des éléments capacitifs (C1, C5) sont montés en série dans les lignes (10, 11) reliant la première source aux pôles du gap d’usinage (G). En outre, ces pôles peuvent être reliés par une bobine de self induction (Lm) montée en série avec une source de courant continu réglable (Sm). Grâce à ces caractéristiques, l’énergie des décharges érosives peut être réduite de façon importante pour obtenir un usinage de superfinition de grande qualité, tout en contrôlant précisément la tension moyenne aux bornes du gap d’usinage.
Abstract:
Procédé et dispositif d'usinage par électroérosion selon lequel une pièce (2) est usinée au moyen d'un outil (1 ) selon un front d'usinage qui recule devant l'outil sous l'effet de décharges érosives. La pièce et l'outil sont séparés l'un de l'autre par un gap d'usinage. Une séquence cyclique d'impulsions de tension électrique (U ign ) est appliquée entre l'outil et la pièce pour engendrer les décharges érosives. L'outil est mis en mouvement selon plusieurs axes (3, 4, 15) par rapport à la pièce. Les décharges érosives sont séparées entre elles par des temps de pause (TS). Une grandeur représentative (TD moy ) de la largeur du gap d'usinage est mesurée (7, 10, 11 ) en temps réel. Le procédé et le dispositif sont caractérisés en ce que les variations de la largeur du gap d'usinage sont contrecarrées au moyen d'une boucle de réglage permanente (5, 7, 10, 11, 16, 20, 9, 6, 5) qui pilote la puissance moyenne d'usinage (P moy ) selon une loi continue qui fait dépendre le temps de pause (TS) de la grandeur représentative de la largeur du gap d'usinage (TD moy ). Ladite boucle interne n'induit aucun mouvement d'axe. Grâce à ces caractéristiques, on obtient un procédé et un dispositif d'électroérosion présentant une régulation très rapide, quasi instantanée, éliminant les défauts dus aux inerties mécaniques.
Abstract:
The machining liquid (7) comprises a load (9) of particles contained in a dielectric liquid (8). The particles are carbon microfibers (10), sectioned or not, having a diameter (e) comprised between 0.2 and 8 micrometers and a length (l) which is a function of the machining gap (G) provided between the electrode-tool (5) and the electrode-workpiece (6). Thanks to this load of carbon microfibers of well-defined dimensions and geometry, the electro-erosion output, the precision of machining, the condition of the surface obtained and the ability to replicate machining performances, are considerably improved.
Abstract:
The device for machining by electroerosion comprises an electrode-tool (EO) and an electrode-workpiece (EP) constituting the opposite poles of a working gap (GA) and an electrical circuit with a double voltage source (UD) connected to a supply network (A) arranged so as to produce erosive discharges between the electrode-tool (EO) and the electrode-workpiece (EP). This double voltage source (UD) comprises a first (U1) and a second (U2) voltage source connected galvanically to each other by their poles. This double source (UD) is connected to the working gap by at least four separate branches (B1 to B4) of which at least one comprises a self-induction element (L1, L1). Switching means (SW1, SW2) permit producing by selective connection of said branches at least two increasing current slopes and at least two decreasing current slopes. These branches are arranged such that the excess self-induction energy of the electrical circuit, not consumed by the erosive discharges, will be returned to the double source (UD). Transfer means (PO) serve as a current pump to carry out an energy transfer between the two voltage sources (U1, U2) of the double source (UD). This device thus permits obtaining an electroerosion generator applicable to any type of electroerosion with current impulses having a programmable profile that comprises at least two different increasing slopes and two different decreasing slopes. Each of the sources can be connected to the supply network (A). The electrical energy is entirely devoted to machining, with a substantial saving of energy.
Abstract:
The invention is related to asurface treatment method employing electrical discharges, of which the parameters are chosen so as to minimize the removal of material and to counteract the phenomenon of localization, discharges which strike in an intermediate space between a tool-electrode and a part- electrode, or gap, filled with a dielectric liquid and enabling defects to be eliminated associated with the residual white layer produced by electrical discharge machining during resolidification of part of the material melted by the erosive sparks and to obtain, at the surface of part-electrode, a non-crystalline amorphous structure that can replace all or part of 15 said white layer, said method being characterized by the use of two types of powder, the first type consisting of nanometric sized particles, the second type consisting of micrometric sized particles, and the size distributions of the 8particles of the first and second types being different.
Abstract:
Machining liquid for electroerosion, composed of a stable, homogenous dispersion of conductive or semi-conductive lamellae in a dielectric liquid. Said lamellae are of metal or graphite, and have a mean diameter of preferably between 10 nanometers and 50 microns. The dispersion may contain a surface-active or electrolytic agent.