GB191506801A - An Improved Method and Apparatus for Measuring Angular Velocities, especially for Directing Artillery Fire. - Google Patents

Abstract

6801. Wilson, J. S., and Dalby, W. E. May 6. Modifying scale of readings; dials and scales.-Relates to means for measuring the angular velocities in altitude and azimuth of moving targets such as aircraft and comprises an arrangement consisting of a base-plate adjustable about two axes at right-angles, one being horizontal, and also about a third axis which is vertical, a sight carrier or frame adjustable about an axis at right-angles to the base-plate, and means for rotating the frame relatively to the base-plate to follow the movement of target, together with means operated thereby for measuring the rate of angular movement. In the form shown in Figs. 2 and 3, the base-plate a is adjustable about a universal joint member c and also about a vertical pillar d. Telescopic or other sights are carried by a frame e mounted so as to be rotatable about the axis of the base-plate a and geared thereto for that purpose by a worm f engaging the toothed periphery of the base-plate. The worm f is mounted on a spindle h, adapted to be rotated by a handle k or by clockwork or power regulated by hand in causing the sights to follow the target. The rotation of the shaft h is transmitted through a shaft l to a speed indicator n, thereby enabling the angular velocity of the target to be measured. In the form shown, the drive is transmitted through reversible ratchet gearing m, so that the spindle l is constantly driven in the same direction. In an alternative form, the ratchet gear is dispensed with, the speed-indicator pointer being in this case movable to either side of a central zero mark. The device may be adjusted about the joint c to enable observations to be made either in altitude or azimuth or in inclined planes. The speed-indicator dial may show angular corrections instead of angular velocities and mav show a series of corrections according to various ranges. In an alternative form, an indicator having a single series of corrections may be used in conjunction with a disk-and-roller variable-speed gear interposed between the shafts hand l, the gear ratio being adjusted according to range or time of flight.