| 摘要 |
893,795. Drilling. FOSDICK MACHINE TOOL CO. May 1, 1958 [May 1, 1957], No. 13987/58. Class 83 (3). [Also in Groups XXIV and XXXVIII] Apparatus for setting a machine element 15 in a position determined by recorded data, e.g. on punched cards or tape, comprises means responsive to an electric signal for selecting measuring elements 28, 30, 31, corresponding to a dimension required and for mechanically moving the elements to determine the position of the element. In a jig-boring machine having a table and slide both automatically positioned by similar means, the measuring elements for the table are carried in rotary containers and on rocker arms and the selected elements are moved into line with one another as described in Specification 831,654. Thus, as the table 15, Fig. 26, is moved to a desired position, the selected ten-inch rods 30, the inch rod 31, and the decimal rods 28 are positioned between a rod 35 on the table and a feeler rod 33 mounted on the slide 13. When a cycle-start switch is pressed, the table is first moved to the left until a selected one of a number of back-off switches 60-63 is actuated by the table. This backing-off movement allows the selected measuring elements to be moved into position. Whereas, in the previous Specification, the rods were selected by setting dials rotated by hand, in the present machine the dials 24 each carry a gear which can be rotated by a motor 186 according to the setting of solenoid-operated clutches. Moreover, gears rotated with the dials each carry a brush which sweeps a circle of studs which can be selectively energized by the programme to determine the set position of each dial. These stud circles are shown in Fig. 26 connected to the programme reader. When a brush reaches an energized stud selected by the reader, the associated clutch is disengaged and the dial comes to rest. When a positioning switch 57 is depressed the table is traversed by a motor 36 through a screw 18 engaging a nut 38. Near the required position, the motor 36 is stopped by a switch operated by the feeler rod 33 and a motor 37 is started to rotate the nut 38 through gearing 41 to move the table slowly to the final position. The motor 37 is then momentarily reversed to relieve the driving stress. As illustrated, the table 15 is then set at a position 37.9625 inches from a previously set reference. This reading is indicated visually on the dials 24. The programming circuits may be interconnected with the drill head motor to initiate the drilling operation at required rotational and feed speeds. A manual stop switch 278 stops the whole machine in an emergency. A manual switch 281 allows the dials to be set by hand. U.S.A. Specification 2,674,706 also is referred to. |
