| 摘要 |
1,183,586. Tool-changing. ALFRED HERBERT Ltd. 2 June, 1967 [4 June, 1966], No. 24985/66. Headings B3B, B3K and B3T. In a machine tool a head 10, Figs. 1 and 3, comprises two tool spindles 17, 18 in a unit 14 which can be indexed to bring one spindle to an operative position and the other to a toolchanging position, axially-disengageable clutch means 20, 21 holding the unit in position relatively to a body part and radially-disengageable driving means 27, 28 for each spindle in the operative position. The head 10 is adjustable vertically on a column 13 carrying a belt or drum-type toolchanger. Each spindle carries a gear 27 which, with the spindle in the operative position, meshes with the gear 28 driven at high or low-speed according to the setting of an hydraulicallyoperated sliding gear-change or at a creep speed drive through a slipping clutch. When a spindle is turned to a tool-changing position, a plunger (41) engages a notch 40, Fig. 9, in a disc 39 to position a key 42 for engagement with a new tool. In operation, the work-saddle 12 is moved away from the operative tool and the main input clutch to the change-speed gearing is disengaged. The operative spindle is then driven at a creep speed and a rack 49, Fig. 6, is moved axially to rotate sector gears 45, 46 and position a pawl 38 to enable it to engage a ratchet wheel attached to the gear 28. A rack 24, Fig. 3, is then moved axially to rotate a gear 23 and allow balls 26 to move out of contact with cams 25a and allow a spring 26a to move the shaft 19 of the unit 14 axially, thus disengaging the clutch 20, 21. The axial movement causes engagement of a clutch 51, 52 and disengages gears 28, 55 from the spindle gears 27 which are each held from rotation by a detent 100. The unit 14 is then indexed by movement of a rack 53 engaging a gear 54, and the rack 24 is operated to return the parts to their operative positions. The creep drive is disengaged and the rack 49 is raised to enable the spring 44 to disengage the pawl 38 and to rotate a gear 50. The gear 50 rotates gear 55 through a one-way clutch (56) to rotate the gear 27 in the toolchanging position to position the spindle angularly to receive a tool. |
