GB146310A - Apparatus for testing the sighting devices of ordnance - Google Patents

Abstract

146,310. Krupp Akt.-Ges., F. Aug. 10, 1918, [Convention date]. Sights.-Consists of apparatus for testing whether the axes about which the sight is adjusted for range and deflexion are respectively parallel to and perpendicular to the axis of the trunnions, and for testing the graduations of the range and deflexion scales. The apparatus comprises an auxiliary telescope, mounted by a special holder on the gun carriage, acting in conjunction with a collimator mounted on the sight-bar in place of the usual sight. In a modification, the collimator is mounted on the carriage and is used in conjunction with the ordinary sight or with the auxiliary telescope mounted on the sight-bar. In the construction shown, the auxiliary telescope J is mounted on a jointed bracket N<2>, N<3>, N<4> fixed to the carriage C. Fine adjustment screws n<14> and q<3> are provided for setting the direction of the optical axis of the telescope, and fineadjustment screws q<4> for rotating the telescope on its axis to adjust the angular position of the cross-wires i<1>, Fig. 10. The telescope J is used in conjunction with a collimator K, Fig. 8, fixed to the sight-bar G in place of the sight G<1>, Fig. 1. The collimator has cross-wires k<1>, k<2>, Fig. 10, one of which is graduated to show angles, and can be rotated on its axis by fine adjustment screws m<2>, Fig. 9. To test whether the axis d<2> of the sight-bar is parallel to the trunnions, the telescope J and collimator K are first adjusted parallel to the bore of the barrel, the intersections of the cross-wires of the two instruments will then coincide; the sight-bar is then elevated to the maximum amount, and the gun correspondingly elevated to bring the horizontal wires again into coincidence; if the intersections of the cross-wires show lateral displacement, as shown in Fig. 10, the axes of the bar G and trunnions are not parallel and must be adjusted. To test the axis d<4> about which the sight is turned for deflexion, the collimator cross-wires are first adjusted so that when the sight-bar is elevated the intersection of the telescope cross-wires remains on the vertical cross-wire k<2>, the sight-bar is then brought back to zero and deflected; if the intersection of the telescope cross-wires moves off the horizontal wire of the collimator, the axis d<4> is not perpendicular to the axis d<2>. The tangent elevation and deflexion scales are tested by means of the graduated cross-wire k<2> used first vertically and then horizontally.