Patent GB-1493376-A (GB)
Title: Ammunition feeder
IPC: F41A15/00
Filed: 1974-10-03
Abstract: 1493376 Ammunition feeder GENERAL ELECTRIC CO 3 Oct 1974 [3 Oct 1973] 43000/74 Heading F3C An ammunition feeder, for a gun having a longitudinal reciprocating gun bolt 74, Fig. 1, has a first ammunition round transfer means which is driveable at a uniform velocity to advance a train of rounds of ammunition into the gun and has a second ammunition round transfer means which is driveable at a non- uniform velocity and receives rounds of ammunition from the first transfer means, each received round being moved along a path which is transverse to the longitudinal axis of the gun bolt 74 and into engagement with said gun bolt. Each ammunition round transfer means is a rotatable sprocket. The second transfer means includes case ejector means, the latter also being a rotatable sprocket. The gun comprises a housing 10, a barrel 68, a reciprocable bolt 74, and a rotatable mechanism for the bolt. The barrel 68 reciprocates and drives the mechanism or the latter is driven by an external source. The mechanism has a rotatable tubular means, a first coupling means for interengaging the barrel 68 and the tubular means so that rearward movement of the barrel can rotate said tubular means, and a second coupling means for interengaging the bolt and the tubular means so that rotation of the latter provides rectilinear rearward movement of the bolt which, in use, is accelerated with respect to the movement of the barrel. In operation a round R1 is locked in position and a solenoid 174, Fig. 9, is energized. As cam 204, Figs. 1 and 3, drives head 72 of the gun-bolt 74 into its fully locked position in cavity 186 of barrel extension 60, firing-pin actuator arm 140, Fig. 8, rides off sear surface 194 and spring 144 drives firing-pin 138 to fire the round. The explosion causes the barrel 68, Fig. 1, and its extension 60 along with the bolt 74 locked thereto, to recoil rearwards. As the barrel extension 60 moves rearwardly, cam-tracks 96, 98 drive respective cam-rollers 92, 94 to rotate rotor 32 and its gear annulus 50. The latter rotates rotor 24, via gears 48, 52 on shaft 42 and gear 54 on the rotor 24. As the rotor 24 rotates together with slide 162, Fig. 9, stationary cam track 148, Fig. 1, drives cam-roller 166, Fig. 9, rearwardly and, consequently the slide 162 and cam-roller 168. The latter drives gun-bolt cam-track 146, Fig. 1, rearwards, together with the bolt 74. The slide 162, Fig. 9, accelerates the rearward movement of the bolt 74, Fig. 1, with respect to the barrel extension 60. Rearward movement of the barrel 68 and the bolt 74 compresses barrelreturn spring 84 and bolt-return spring 192. The used cartridge case is transversely ejected and a fresh round is transversely injected. The spring 192 drives the bolt forward with the fresh round to insert the head 72 of the bolt 74 into bore 70 and chamber the round. The arm 140, Fig. 8, abuts the sear surface 194 and compresses the spring 144. Cam 204 moves arm 200, Figs. 10B, 11B, so as to rotate the bolt to its locked position. If another round is not to be fired, the solenoid 174, Fig. 9, is de-energized, spring 180 urges dog 178 into engagement with shoulder 172 on the rotor 24 to prevent rotation of the latter. The rotor 32, Fig. 1, continues to rotate, the shaft 42 is subjected to torque and the rotor is consequently halted. The wedging angle of the cam-tracks 96, 98 prevent reverse movement of the rollers 92, 94 respectively and reverse rotation of the rotor 32. Subsequent energization of the solenoid 174, Fig. 9, untwists the shaft 42, Fig. 1, to accelerate the rotor 24 to permit the bolt-return spring 192 to drive the bolt 74 into the chamber and be locked therein. The gun is charged initially by an external source of power driving the rotor 32, the rollers 92, 94 travelling in annular cam track 100. The ammunition feeder injects one round of ammunition between extractor lugs of the bolt during rear dwell of the bolt and ejects the case of the previously fired round, being driven by the shaft 42 and rotor 32. The shaft 42 has a gear 201 and an intermediate sun gear 202, the latter meshing with planetary gears 204 which are journalled on a spider 206 and are in mesh with a stationary annular gear 208. The spider 206 has an annular sun gear 210 which is meshed with a pair of planetary gears 212 journalled on a spider 214 and meshing with the gear 208. This planetary system provides a 16 : 1 reduction. The spider 214 is integral with a tubular shaft 216 coaxial with the shaft 42. A forward stripper sprocket 218 and an aft stripper sprocket 220 are fixed to the shaft 216. The stripper sprockets engage the leading round R2, Fig. 5, in a train of linked ammunition and draw the train past a link positioner 222, Fig. 6, forward outer link guides 224 and 224A, aft outer link guides 226 and 226A, a forward stripper guide 228 and an aft stripper guide 230 to strip and eject each link from the respective rounds of ammunition. The stripper sprockets each have four cusps and rotate at a uniform velocity, one-fourth the rate of the gun. The gear 201, Fig. 7, is meshed with a reduction gear 232, which is fixed for rotation with an elliptical gear 234, the latter being meshed with an elliptical gear 236 which is fixed for rotation with an idler gear 238 meshing with a gear 240 which is fixed to the injector shaft. The injector shaft thus rotates at a sinusoidal velocity once per gun cycle and carries the cam 204. A forward injector sprocket 242, Fig. 5, and an aft injector sprocket 244 are fixed to the injector shaft. The gear 201, Fig. 7, is also meshed with an idler gear 246 which is meshed with a gear 248 which is fixed for rotation with an elliptical gear 250, the latter meshing with an elliptical gear 252, fixed for rotation with a gear 254 meshed with a gear 256 which is fixed to an ejector shaft 258. The latter has fixed thereto a forward retarder-ejector sprocket 260, Fig. 5, and an aft retarder-ejector sprocket 262. In operation the stripper sprockets rotate counter-clockwise at uniform velocity to continually pull the train of ammunition at a uniform velocity into the feeder and to strip and eject the leading link. The stripped round is guided by guides 228, 230, Fig. 6. The stripper sprockets hand the round to the injector sprockets 242 and 244, Fig. 5, which are substantially motionless, the round being retained by the substantially motionless retarder-ejector sprockets 260 and 262. When the bolt is in its rearwardly position, the sprockets 260, 262 rotate counter-clockwise to eject the fired case from the extractor lugs 122 and along guideways 264,266. Concurrently, the injector sprockets 242, 244 rotate clockwise to advance the fresh round into the extractor lugs 122 and then continue to rotate to receive the next round from the stripper sprockets. The round is prevented from tilting by the retarderejector sprockets 260, 262.