GB210751A - Improvements in and relating to the gun carriages and sighting apparatus of field guns for correcting the varying transverse and longitudinal inclinations of the gun carriage - Google Patents

Abstract

210,751. Schneider et Cie. Feb. 3, 1923, [Convention date]. Sights.-To correct for transverse inclination of the gun carriage on inclined ground, the lowercarriage is cross-levelled about a longitudinal axis, the correction for longitudinal inclination of the gun carriage being effected by first adjusting the sighting apparatus in the vertical plane and then elevating the gun on its trunnions to restore the aim. In the form shown in Fig. 1, the. cross-levelling is effected from the right-hand side of the gun by a worm-gear A<5> which rotates the lower carriage A<1> in a longitudinal bearing H<1> fixed to the wheel axle H. The training of the gun by a worm gear D, the elevating of the gun by a worm gear G<1> and toothed gear E, F, and the uprighting of the sight S by a screw gear p<2>, are all performed from the left-hand side of the gun. The sighting apparatus is carried by a box J adjustable on an extension K of the gun trunnion C<1>, Fig. 5, by the screw gear p<2>, and the box is connected with an elevation drum M by epicyclic multiplying gear n, m, the planetarypinion n of which is carried by an arm N fast with the extension K. The elevation is read off against an index-mark fixed to the interior of the box J. To correct for longitudinal subsidence, the sight is first levelled by operating the gear p<2> to the reading of a bubble Q<2> on a spirit level previously set by a handle q for " angle of site." The gun is then moved by the elevating gear until the selected graduation on the elevation drum is restored. In a modification, the elevating and sight setting is performed from the left-hand side of the gun, and the cross-levelling and training from the right, a special training sight being provided. In a fur. ther modification, Fig. 9, the gun elevating and cross-levelling is performed from the right, and the sight elevating and training from the left. In this case the box J carrying the elevation drum M is mounted on the right-hand gun trunnion and through a transverse shaft R receives angular movement corresponding to the adjustment of the sight bracket P about the pivot L by the gear p'. Specification 172,627, [Class 92 (i), Ordnance &c. mountings], is referred to.