| 摘要 |
778,713. Removing metal by electric discharge. SPARCATRON, Ltd. July 15, 1953 [April 16, 1952], No. 9537/52. Class 83 (4). In a self-contained electro erosion unit a casing 1 mounts an electric motor and in a separate compartment at one end of the casing a rotary electro-erosion tool 25 is coupled to one end of the motor shaft 6, the other end of the shaft having a projection for driving a pump 11 supplying liquid to the tool vicinity during working. The casing is mounted on a hollow bed-plate 3 providing a receptacle 40 for the bathing liquid from which a pipe 41 leads to the pump which is carried by an end-plate 4 of the casing with a labyrinth seal 9 between the pump and casing. The liquid fed from the pump is delivered by a nozzle 43 adjacent the tool and the workpiece 35 supported on the bed, to fall with any swarf into a tray 44; the liquid being filtered at a wall 45 before returning to receptacle 40. The annular tool 25 is carried by a plate 26 on a journal 27 connected to the shaft 6 and a copper slip-ring 29 on the journal is contacted by a brush 30 to supply current to the tool (negative polarity) to promote spark erosion. A disc 37 isolates the tool from the slip-ring &c. The pump may be of the centrifugal type and control means for the relative movement of the tool and workpiece as described in Specification 724,524, [Group XXXV], and tools as described in Specification 724,521 may be employed. Specification 637,872 also is referred to. |
