Patent GB-126784-A (GB)
Title: Improvements in Sighting Apparatus for Ordnance.
IPC: F41G5/08
Filed: 1918-05-14
Abstract: 126,784. Wolseley Motors, Ltd., and Reeve, E. May 14, 1918. Sights and methods of sighting.-Consists in anti-aircraft sighting apparatus having means for determining the elevation and bearing angle of the gun and the fuse-setting, after correcting for the angle of sight, speed of target and wind, and having as its main feature an arm which can be set off from the line of sight by an angle equal to the vertical angle through which the target moves from the " sighting " to the " striking " position. In the complete apparatus, the sights are mounted to move in altitude on a table capable of rotating in azimuth. The table also carries a range-finder, speed-indicators, an arm which moves with the sights and indicates the angle of sight, a second arm pivoted about the same axis and adjustable to represent the striking position of the target, a third arm adjustable to represent the required elevation of the gun, and mechanism to determine the lateral deflexion to compensate for the speed of the target and the wind. In the construction shown, two sighting telescopes F, F' are fixed to a rotary horizontal shaft F<2> which also carries a graduated arm G parallel to the line of sight. The sights and a range-finder R are carried on a rotary table A. Sliding on the arm G is a sleeve g which is connected to the operating mechanism of the range-finder by gearing so that it is moved along the arm to a position representing the range. A second arm H, also graduated in ranges, is adjustable about the axis of the shaft F<2> and carries a. sliding sleeve h which is connected to the sliding sleeve g by a link P adjustable in length to represent the distance travelled by the target in the time of flight of the projectile plus the lost time, this distance being determined by any suitable speed measuring and calculating apparatus. The sleeve h is pivoted to a sleeve n<3> sliding on a. horizontal bar N adjustable to represent the height. The sleeve n<3> carries an upright Q on which is a slide q carrying a pivoted sleeve k sliding on an arm K. The slide q can be adjusted along the upright Q to a height above the bar N representing the drop of the projectile due to gravity, and the arm K then indicates the angle of elevation of the gun. This angle is communicated to the gun by means of a toothed quadrant k<1>, carried by the arm K, and transmitting gearing or apparatus. The upright Q can be adjusted along the sleeve n<3> to compensate for wind. The arm K and upright Q are preferably graduated in fuse times. Rotation of the table A operates a spindle b, Fig. 9, which has a pinion b<1> engaging a fixed toothed wheel E on the stand, and the spindle, through gearing, communicates the bearing angle to the gun. The deflexion angle due to speed of target and wind is added to this bearing angle by mounting the spindle in a box B' which is adjustable about the centre of.the table. A speed-indicator U operated by the range-finder and representing rate of change of range is provide to enable the striking range, which is set on the arm H, to be determined. Instead of using the distance-arm P to determine the angular setting of the arm H, a speed-indicator, operated by the shaft F<2> and indicating the vertical component of the angular velocity of the target, may be used in conjunction with a rotary calculator. The horizontal component of the angular velocity of the target is shown on a speed indicator W operated by the training gear of the table.