| 摘要 |
In an automatic bar and wire pointing machine, workpiece-feeding means comprises a carrier having two feeding wheels (38,40) mounted on a driving shaft (20). Each wheel comprises a circular pitch plate (42) providing four sets of six notches (N1, N2, N3, N4) spaced uniformly around its periphery; the notches form semi-circular recesses (R1, R2, R3, R4) of different diameters to accommodate different sizes of workpiece, and the recesses are all centered on a common pitch circle (P) of the pitch plate. The wheel comprises also a picker plate (44) comprising six lobes (66) which are spaced uniformly about the axis of the wheel and form radially-projecting edges (68) positioned adjacent to the notches of any selected one of the four sets of notches. Indexing means for rotating the carrier in uniform steps, successively to pick a workpiece from a rack (72), bring it to a machining position and deposit it on to an unloading ramp (74), comprises a treadwheel (82,84) secured to the driving shaft and having projecting spokes (102) to be engaged successively by an actuating cylinder (124). |
