Patent GB-1136001-A (GB)
Title: Improvements in turret drilling machines
IPC: B23B39/20
Filed: 1966-03-04
Abstract: 1,136,001. Turret drilling machine. GOTTHILF STARK [trading as GOTTHILF STARK]. 4 March, 1966 [5 March, 1965], No. 9723/66. Heading B3C. A turret drilling machine comprises a plurality of drill spindles 38, Figs. 1a, 1b, each of which is provided with its own gearing 39 and removably fitted into an indexable drum 78, the latter being indexed so that each of the spindles 38 is aligned with a drive spindle 12, which is axially movable into driving engagement with the spindle. The drill spindle 38 to be lowered is held axially by a holder 32 and moved axially by a member 24. The holder 32 and member 24 are slidably mounted on a bolt 31. The spindle holder carries an arm 33 which engages beneath a plate 57 on the drilling spindle. A drive motor 2 pivotally secured on the housing 1 drives spindle 12 through a V- belt 6, stepped pulleys 5 and 16 and an electromagnetic clutch 17. An engaging member 61, Fig. 4, rotatably mounted on the spindle 60 and capable of axial movement therewith, engages a linkage 63 on which various switch dogs 64 are adjustably secured. The switch dogs 64 co-operate with end switches 65-68 which are responsible for the fast motion, working motion, reversal of direction of rotation, and reverse fast motion of the spindle 38. Spindle 60 is splined to spindle 50 and is formed with a lead screw 59 which co-operates with a nut 58 when using a screw cutting tool. The member 24, Fig. 1a, is moved on the bolt 31, by a pressure controlled working piston 118, Fig. 5, or by a manually operated rotary slider. The piston 118 moves downwards and entrains the setting member 24 and by means of the arm 23 also entrains the drive spindle 11 which finally enters and couples with the clutch port (41), Fig. 3 (not shown), of the drill spindle. One the end of the drive spindle 12 there is arranged a dog clutch 29 and a brake disc 26 which co-operates with a spring loaded bolt, the radial arm bearing for the setting member 24 being fixed against a bell shaped coupling 25. The setting member on downward movement, operates an end switch 123, Fig. 5, to effect the high speed feÚd motion of the drill spindle 38. At the same time through one of the stops 122 on switch 123 the electromagnetic clutch 17 is engaged so that the drive spindle 12 and drill spindle 38 are driven. The high speed feed motion is switched off by co-operation of a stop 70 on the gear-box 39 of the drill spindle, with an end switch (72), Fig. 2 (not shown), and the drill spindle moves further at a working fast rate. A working stop 69, Fig. 1a runs against a fixed stop 75 after it has operated an end switch 74 which through a time relay terminates the feed of the drill spindle. High speed reverse movement then commences and the setting member 24, with the spindle holder 32, ascend. The arm 33 of the spindle holder strikes on a stop 37 adjustably secured on the housing 1, and is held fast in this position while the setting member 24, and drive spindle 12, are disengaged, and when the end switch 123 is reached, the electro-magnetic clutch 17 is disengaged. A geared motor 89, Fig. 1b drives a spindle 83 on one end of which there is secured a double lever 81, Fig. 1a with rollers 82 which engage in slots in the shift drum. The end switch 123, Fig. 5, has the effect that directly after the upward movement of the setting member 24, the geared motor 89 is switched on, which rotates the double lever 81 through the chain 87. On engagement of the double lever 81 the shift drum is indexed so as to be moved by one step (e.g. 60 degrees), and the drill spindle runs with its gear-box up on to the ring 95 on the guide spindle 76, Fig. la, and is held thereby while the next drill spindle comes into engagement with the arm 33 of the setting member 32, and is held fast in axial direction. The movement of the double arm lever 81 is terminated so that the lever arm which is not in engagement, comes into abutment with an end switch which switches off the geared motor 89. A shifting slider (103), Fig. 6 (not shown), is secured on the under side of the shift drum 78, which slider acts through levers on a quantity regulator, and is associated with each drill spindle 38, to influence the feed motion speed of the drill spindles.