| 摘要 |
317,636. Drummond, A. Aug. 14, 1928. Tailstooks.-The tailstock spindle of a lathe, milling, grinding or like machine is hydraulically fed and locked. The spindle 5 carries a piston 10 in a double acting cylinder 9 screwed at its front end to a clamping- .collet 7 and normally pressed forward by a spring 14. Ports 16 communicate with a three way reversing valve 19 preferably arranged for operation by the elbow or foot of the operator. In operation, when the centre 6 is forced into engagement with the work the pressure rises and the cylinder is forced back against the spring pressure locking the spindle 5 by the collet 7. In a modification, the spindle is fed by a rack 42, Fig. 2, and locked by a clamping-screw 52. A pinion 44 connects the rack to a second rack 43 formed on a double acting piston in a cylinder controlled by a reversing valve 47 ported as shown. When the centre engages the work the rise of pressure opens a spring loaded valve 45<1> to admit pressure to a second cylinder 50 for rack and pinion operation of a nut 55 on the clamping- screw. Reference has been directed by the Comptroller to Specification 324,042. |
