| 摘要 |
1,141,022. Electrolytic machining. ASSOCIATED ENG. Ltd. May 4, 1966 [May 4, 1965], No. 18834/65. Heading C7B. Electro-chemical machining is carried out wherein the voltage Vo applied from a stabilized power supply 3 between the tool 1 forming a cathode and the workpiece 2 forming an anode is controlled by a signal dependent on the conductivity of the electrolyte E caused to flow at constant rate through a gap G between the tool and workpiece so maintaining throughout machining a constant equilibrium working gap as the tool advance rate is kept constant during removal of workpiece material. The voltage Vo may be controlled by an error signal Ve derived from a comparison circuit 12 fed with the voltage Vo of the power supply 3 and with a control voltage itself derived from two other comparison circuits 10, 8 each fed with reference voltages Vr, Vcr and signals Vc dependent upon and proportional to the conductivity which may be measured by two coupled coils 5a, b immersed in the electrolyte circuit 4. If the electrolyte composition is assumed unchanged, the signal may be obtained by measuring the electrolyte temperature using a temperature sensitive element (21, Fig. 5). The stabilized power supply may comprise a motor driven variable transformer (14, Fig. 2) or a saturable reactor (17, Fig. 3) and a rectifier (15,18, Figs.2 and 3), or a silicon controlled rectifier circuit (20, Fig. 4), each controlled by the signal. |
