Patent GB-199799-A (GB)
Title: Improvements in multiple spindle drilling machines
IPC: B23B39/16
Filed: 1922-03-28
Abstract: 199,799. Wilkins, W. S. March 28, 1922. Drilling - machines. - A multiple spindle drilling-machine, stated to be particularly useful for large constructional work or for the metal work employed on wagons, comprises a supporting frame on which two or more drill units are adjustably mounted, each unit comprising a plurality of spindles adjustable as to their relative positions and angular alignments. separate feeding unit provides for feeding the drill units as a whole when the spindles are parallel, and for feeding the spindles separately along their respective axes when they are angularly arranged. Framing; driving machine spindles, -Each drill unit 41, Fig. 9, is slidable on a base portion 40 adjustably secured to the box frame E by bolts and slots 4, and comprises an electric motor 76 driving a number of spindles 82 through flexible and extensible shafts 81 and gearing 75. The spindles are carried by sleeves 85 mounted on hollow blocks 37 and are secured by encircling straps 86 and bolts 89, the blocks being adjustably supported from brackets 66 by bolts 20 and T-slots. When it, is desired to incline. the axes of the spindles the sleeves 85 are gripped by split blocks 91, Fig. 12, which also grip cylindrical projections 93 formed on the blocks 87. The brackets are formed with ribs 72, Fig. 9 engaging horizontal T-slots formed in the three vertical faces of the unit and are reversible to adjust the positions of the spindles. An arm 98 having a hole 99 above the centre of gravity of the unit provides for lifting by a crane. Any number of frames may be used in conjunction, and slots of T or other section may be substituted for the slots 4 so as to be continuous between adjacent frames. The work is held by a holder or jig secured to T-slots 95, Fig. 1, and may be supported by more than one frame. Feed-motions.-The feeding unit comprises a box structure 15, Fig. 3, either forming a part of the frame as shown or separate and enclosing a shaft 19, driven by an electric motor 17 through change gearing 18, and carrying worms 20 which drive cams 25 acting on adjustable rollers on cranks 29. The cams are designed to give a pause after withdrawal of the drills to allow changing of the work. The cranks are provided with holes 32 located on different pitch circles by means of which links 33 are attached to transmit motion to discs 11 secured to feed shafts 7, Fig. 9, each of which carries an arm supporting an adjustable weight and a pinion meshing with a rack 42. When the drill spindles are parallel the rack is secured to its unit 41 for feeding all the spindles together by two pairs of bolts 55, 56. each pair being arranged at opposite ends of a slot in the unit. When the spindles are inclined, Fig. 12, one bolt of each pair is removed and the remaining bolts, which are free to slide in the slots 57, are secured to a plate 60 having a groove 61 engaging rollers on the spindle sleeves which are thus fed axially on vertical movement of the plate. The feed given to each spindle may be adjusted by varying the shape of the groove. Larger or smaller drills may be used together with speed reducing or increasing means. In modifications of the feeding system, one cam only may be used driving a feed shaft from which all the other feed shafts are driven, and the drills may be fed simultaneously in succession.