Patent ES-306893-A1 (ES)
Title: Improvements in machine-tools
IPC: G05B19/06
Filed: 1964-11-30
Abstract: A machine tool comprises a column 1, Figs. 1, 2, fixed to a base 2, on which is mounted a tool head, a support 5 movable on the column, a slide 4 slidable on the support, and a table 3 movable on the slide, each of the table and slide having bar-means 18 for setting it in a required position. Table 3 is displaced by a lead screw 8 driven by a hand wheel 9, or by a reversible motor 10, through a change speed box 11, a shaft 12 having a torque limiting device 13, and gears 14. Slide 4 can be displaced by a screw 15, which co-operates with a disengageable nut in the slide, or by an hydraulic cylinder 17a. Bar 18 for setting table 3, is fixed to, and is movable with, the latter, and comprises sets of holes 19 which co-operate with a pin 37 carried by slide 4, Fig. 8, for stopping the table in the required position, and also has holes (19a), (19b) &c., Fig. 6 (not shown), which co-operate with feeler controlled contacts 55a-55e, which are arranged to transmit various control signals, so as to control various functions of the machine tool. Bar 18 is fixed at one end to a rotatable stub shaft 21 carried by table 3, Fig. 3, and rests at its other end on a spring-loaded peg 23. The bar can slide and rotate in a support 26 fixed to slide 4, which carries pin 37 and the feelers for actuating contacts 55a-55e. A ratchet-wheel 27 carried by shaft 21 co-operates with a holding pawl, Fig. 9, and also with a pawl 30 actuated by a pivotable hydraulic cylinder 32 against a spring 36. Pin 37 is connected to one end of a lever 38, Fig. 8, which is pivotally mounted at 39 on support 26, and a spring 40 urges the lever so that pin 37 engages a hole 19 in bar 18. Adjacent the end of the lever a ring 41 is fixed to a fluid pressure piston 43, and is adapted to pivot the lever to disengage pin 37 from hole 19. Bar 18 can be displaced axially relative to table 3 by a part conical rod of an hydraulic cylinder 49 which co-operates with a rod 51. In operation, when a boring or drilling operation has been completed, fluid pressure is supplied to cylinder 49, Fig. 3, to relieve the axial pressure on bar 18. Fluid pressure is admitted to cylinder 44, ring 41 pivots lever 38, and pin 37 is disengaged from hole 19, and also actuates a contact 47, which energizes an electromagnetic valve, so that fluid is supplied to cylinder 32. Pawl 30 rotates bar 18 until a contact 54 is actuated, whereupon cylinders 32, 44 and 49 are exhausted, and the table starts to move until pin 37 engages a further hole 19. As lever 38 pivots, it actuates a contact 48 so that the table speed is reduced, and when the pin engages the hole, the table stops, with the rotation of shaft 12, Fig. 1, being absorbed by the torque limiting clutch 13. If the table is to be slowed down before the engagement of pin 37 with a hole 19, an auxiliary pin 56, Fig. 10, which co-operates with a contact 57, is provided. The movement of slide 4 is also controlled by a bar 18, and in this case contacts such as 48, 54 actuate the electromagnetic valves interposed in the supply circuit of hydraulic cylinder 17a. The movement of the tool head can also be controlled by a bar 181, Fig. 13. The holes in the bars may be formed by using a jig 65, Fig. 13. In a modification, the table (66) is rotary, Figs. 15, 16 (not shown), and is carried on a slide (67) slidable on a base (68). The table is rotated by a worm and wheel (69), (70) driven by an electric motor, through a torque limiting clutch and change speed gear-box. An annulus (71) having holes (72) therein is provided around table (66), and these holes co-operate with a pin (371) and feelers of microswitches (551). The holes are produced by using an optical device (73), a circular scale (74), and a portable drill.