GB191507144A - Improvements in Sighting Devices for Airship Repelling Guns. - Google Patents

Abstract

7144. Krupp Akt.-Ges., F. May 28, 1914, [Convention date]. Sights and methods of sighting.-Relates to sights for anti-aircraft guns in which (1) mechanism giving an independent line of sight is employed, the sight being mounted so as to move with the gun in elevation, and being kept on the target during the ranging operation by moving it through an equal and opposite angle to the gun, and (2) the reader of the range scale can be adjusted to a part of the scale which corresponds to the angle of site of the target. The invention consists in adjusting the reader for angle of site during the pointing operation, the range scale being moved with respect to the reader during the ranging operation. Fig. 2 shows in sectional rear elevation the improvements applied to sighting- apparatus of the kind described in Specification 4735/05. The sight bracket b<3> is shown fixed on the gun trunnion b<1> so that, when the pointing- gear D, mounted on the fixed carriage C, is operated, the gun and sight together are moved through an angle equal to the angle of site of the target. The operation of the gear E elevates the gun for range, the sight-bar F being moved, with respect to the bracket b<3>, through an equal and opposite angle by means of the flexible connexions J, J<1>, J<2>, H. The attachment forming the present invention is carried by an arm b<6> attached to the trunnion b<2> as shown in outside elevation in Fig. 2, and in an enlarged sectional view in Fig. 5. The action is as follows. A toothed sector T is first adjusted on the trunnion b<2> with the aid of a spirit level by means of a worm t<3> mounted on the carriage C. The pointing-gear D is then operated, a reader m<1>, during this operation, being moved on to the proper part of a. range scale K divided into four sections corresponding to angles of site from 0 to 15, 15 to 25, 25 to 35, and 35 to 45 degrees. This is effected through sliding parts m<2> , M by a grooved drum N. Fig. 7, which is fixed to a spindle n<2> freely mounted in the arm b<6>and is rotated by the engagement of a pinion r<1> with the fixed sector T through a sun-and-planet gear R, P, S, the wheel S being locked by a worm i<9> on the shaft J<1>. During the ranging operation, the drum K is rotated by a pinion i<8>, Fig. 2, carried by an extension of the shaft J<2>, the reader m<1> being kept on its proper scale, as the shaft n<2> carrying the drum N is prevented from rotating by the action of the sun-and-planet gearing.