Patent GB-930845-A (GB)
Title: Improvements in aiming devices, particularly anti-aircraft gun-laying devices
IPC: F41G5/08
Filed: 1960-03-02
Abstract: 930,845. Aiming devices. OFFICINE GALILEO S.p.A. and N. RICHIARDONE. March 2, 1960 [March 9, 1959], No. 7447/60. Class 92. In an aiming device in which a sighting device (not shown) is moved by motor units 19, 33, Fig. 3, in accordance with the positions of a manually operated control stick 1, the movements of the central stick are transmitted to control means for the motor units through a ratio device comprising two members 7, 8, Figs. 3, 4, shaped as shown and capable of rolling movement on each other so as to maintain contact therebetween, the arrangement being such that movement is transmitted from a rod 5 carrying the member 7 to rod 9 carried by member 8 in greater ratio at or near a coaxial position of the two members 7, 8. The aiming device is based on the assumption that the target, e.g. an aeroplane, moves on a rectilinear course at constant speed and the control stick 1 is moved by a gun layer so that the sighting device maintains a target in a correct aiming position, the aiming device being such that this can be done by movement of the control stick 1 substantially or wholly in one direction only. The stick 1 is mounted in a universal bearing 2 having an outer ring connected to a shaft 3 and the end of the stick 1 is mounted in a ball and socket bearing, the socket of which is connected to a shaft 4. The movement of the stick in the universal joint 2 can be resolved into two directions at right angles (corresponding to horizontal and elevational movements of the sighting device), movement in one direction causing rotation of shaft 3 and in the other direction causing axial translation of shaft 4. These movements are communicated as shown to the rod 5 mounted in a universal bearing 6 such that any movement of stick 1 is reproduced accurately in the movement of rod 5, such movement being transmitted through the ratio device 7, 8 to the rod 9 mounted in a universal bearing 10 having an outer ring connected to a shaft 11. The rod 9 also engages a yoke 13 connected through gears 15, 16 on a shaft 12, the arrangement being such that rotation of shafts 11, 12 are in proportion respectively to desired elevational movement V v  and horizontal movement V 0  of the sighting device. The movement V v  is transmitted to the motor unit 19 via rods 18, 18a, the output of which is directly proportional to the angle of elevation e and a take-off Te serves as the elevational drive for the weapon and sighting device therewith. The movement V 0  of the shaft 12 is converted by a parallelogram linkage 21, 22 and a secantshaped cam 35 rotated proportionally to # from the output of the motor unit 19 to a movement of a rod 32 proportional to V o  sec e which movement is transmitted to the motor unit 33 having an output directly proportional to the angle of traverse a. A take-off Ta drives the weapon and sighting device in traverse movement. The outputs c, a from the motor units 19, 33 are fed to a mechanical integrating device including a wheel and disc arrangement 44, 39 such that a shaft 45 is rotated in proportion to the value of the product of summated changes in a and sin e, i.e., #dα sin #, the rotation being transmitted to an annulus 48 through which extends the control stick 1. The rotation of the annulus 48 is arranged to be in a 1: 1 ratio with respect to the movement of the sighting device in traverse. The arrangement is such that the gun layer can place both hands flat on the annulus 48 and hold the control stick between his thumbs and movement of the stick for target following in one of the directions a becomes minimal and movement is mainly for target following in the other direction e. If required a slotted member 49 secured to the annulus 48 can be slid forward to engage the control stick 1 to permit movement of the stick 1 in one direction only. In another electro-mechanical form of the device, Fig. 5 (not shown), the arrangement is such that the control stick 50 has freedom of movement only in one plane.