Patent GB-190809676-A (GB)
Title: A System of Electro-magnetic Control of Distant Mechanisms.
Inventor: FROMAGET PIERRE
Filed: 1908-05-04
Granted: 1909-03-11
Abstract: 9676. Fromaget, P. May 4, 1907, [date applied for under Section 91 of Patents &c. Act, 1907]. Sights and methods of sighting.-In a system of electric control from a distance of a number of mechanisms, such as the sights of guns, the electromagnetically - operated ratchets that cause the movements of the controlled mechanism advance synchronously with a similarly-operated ratchet at the controlling station. The actuating solenoids a, a<1>, a<2>, Fig. 1, at the controlling and the controlled stations are all in parallel, so that at any moment all or none of the solenoids are'energized. At the beginning of the oscillation of the ratchet mechanisms, the circuit through the actuating- solenoids at the controlling and controlled stations is completed between the mains through switch contacts j, j<1>, j<2> at all the stations, these contacts being arranged in series. The motion of the cores following on the energization of the solenoids effects the forward movement of the ratchet-wheels at all the stations, and causes the switch arms to break their series contacts at j, j<1>, j<2> ; but before the complete break of any of these series contacts, the switch blocks j, j<1>, j<2> make contact between fixed blocks g, h, g<1>, h<1>, g<2>, h<2>, so that the circuit through the actuating-solenoids is not yet broken. The solenoids then further attract their cores until the contact-blocks j, j<1>, j<2> reach the upper edge of the inclined plates h, h<1>, h<2>, whereupon springs o, o<1>, o<2>, which have been put in tension by the motion of the contact-blocks along the inclined plates, draw these blocks away from the plates g, g<1>, g<2>, and thus break the contact. The contacts g, h, g<1>, h<1>, g<2>, h<2>, however, are arranged in parallel so that the solenoids a, a', a<2> are not de-energized until the last of these contacts has been broken. The switch arms, after the break of the last contact, synchronously start on their return journey under the influence of springs, the contact-blocks then sliding along the outside of the plates h, h<1>, h<2> until, escaping at the under edges of these plates, they re-make the series contacts at i, i<1>, i<2>. Since, however, these contacts are in series, the circuit through the actuating-solenoids is not completed until the last switch has made contact, so that the repetition of the cycle of operations starts synchronously at all the stations. The ratchets at all the stations are thus advanced until a brush m, bearing on a helical contact-piece at the controlling- station, touches an insulating-segment n and thus breaks the circuit. In the practical apparatus shown in Fig. 2, in which the provision of two solenoids in each instrument allows the movement of the mechanism in either direction, the reciprocating solenoid cores 8 carry pins 11 which, engaging in slots in the switch arm of the instrument, cause the latter to move as a core reciprocates. At the same time, the pawl 10 engages with the teeth of the ratchet - wheel 1, causing the wheel to rotate. A check pawl 14 controlled by the actuating-pawl 10 prevents the over-rotation of the ratchet-wheel. When the apparatus is used for controlling gun-sights, the wheel 1 drives through gearing a second wheel 38, Fig. 4, the circumferential surface of which is a surface of revolution, the generator of which is the arc traced by the end of the lever 40 which actuates the gun-sights. In this surface is cut a helical groove in which a roller 36 on the end of the gun-sight actuating-lever rests, so that when the wheel 38 is rotated the gun-sight is moved.