Patent GB-186415-A (GB)
Title: Improvements in or relating to multiple-spindle drill-heads
IPC: B23B39/16
Filed: 1921-06-24
Abstract: 186,415. Hey, G., and Wilding, J. A. June 24, 1921. Attachments for drilling.-In a miiltiple-spindle drill-head of the type in which a support attached to the machine spindle carries a central gear which drives two or more drill sockets through gearing on intermediate parallel shafts carried by the support, the central gear meshes with the lower portion of each intermediate gear-wheel, the upper portion of which meshes with the pinion on the drill socket, so as to reduce the height of the drill head to a minimum. In the form shown, the support 10, which is attached to the rack sleeve 11 of the machine spindle, has a head 12, in which is mounted in bearings 15, 16 the driving-spindle 13, which is secured by a tang 14 into the machine spindle and is provided with a central drill 18 and a central gear-wheel 17. The support has a series of pairs of lateral eyes 21, 20, each of which is bushed to form a bearing for an intermediate wheel 23, 24, the lower part 24 of which meshes with the wheel 17. The parts 23, 24 may be of the same or different diameter. Each drill-socket 26, to which is keyed a pinion 43 meshing with the wheel 23, is mounted in a bracket 25 having upper and lower bushed lugs 28, 27 mounted with eves so that the bracket may be angularly adjustable about the axis of the intermediate wheel. The bracket is secured in position by a bolt 29 and nut 30, in order to facilitate mounting and dismounting, the bolt forming the axle of the intermediate wheel and passing through the eyes and lugs. The bushes 33, 32 in the lugs may be separated from the outer surfaces thereof by distance-pieces 35, 34, which, however, may be replaced by lugs 128, 127 on a second bracket 125. when it is desired to mount two drill brackets on the .same bolt. The lengths of the lugs on the brackets 25, 125 may be different so as to secure a greater degree of adjustability of the drill head. In this case the pinion 43 on the second bracket, which meshes with the same intermediate wheel, is on a lower level than that on the first bracket in order that the brackets may be swung close together without the pinions fouling one another. More than two drill brackets may be mounted on the same bolt. The bushes 33, 32 and distance-pieces 35, 34 may be replaced by three-diameter split bushes 40 having separate shoulders for engaging the lugs on the separate brackets. Each drill-socket may be independently adjusted axially through its pinion 43, in order to drill at various levels, by a rack sleeve 51 and pinion 53, the pinion being mounted on and pinned at 56, Fig. 3, to a bolt 54 in the split upper end of the bracket and rotated by a key inserted in holes in the bolt. The socket is clamped in adjusted position by a nut 57, which engages a tapered washer 58. In a modification, the eyes 21, 20 are provided on internally flanged sleeves, which are mounted, on the support 10 so as to be angularly adjustable thereon and so as to be capable of being removed therefrom together with the intermediate wheels and brackets and replaced by others of different size.