GB712867A - Improvements in belt feed mechanisms for automatic firearms - Google Patents

Abstract

712,867. Automatic firearms; belt-fed mechanism. BREVETS AERO-MECANIQUES SOC. ANON. March 26, 1952 [March 27, 1951], No. 7788/52. Class 92(2) Relates to belt feed mechanisms for automatic firearms of the type in which power is supplied on the firing of each shot, to a transmission system comprising two rotating elements of which one is actuated by the power device and the other drives the belt, there being prestressed elastic means tending to take up a degree of angular play provided between these elements. According to the invention, this play corresponds to only a portion of the full movement necessary to advance a round, and the elastic means is so constructed that the play between the two elements is fully taken up after each round is advanced. The barrel 1 and casing 2 of the gun shown recoil together with respect to a fixed support 6, and the breech-block is actuated by gas piston means 5. The cartridge feed mechanism 9 is carried by the fixed support 6. When the gun recoils a roller 22, Fig. 5, on a lever 20 carried by the casing 2 rides up a ramp 23 on a plate 13<SP>0</SP> of the mechanism 9, and serves to lift a spring-controlled slide 16 carrying a pinion 19, see also Figs. 6 and 7. Pinion 19 meshes with pinions 27, 28, fitted with ratchets engaged by pawls 31, 31<SP>0</SP>, in such manner that only pinion 27 is rotated by the pinion 19 during recoil and 28 on the return movement. Pinion 27 is fixed to a sleeve 35 having a degree of lost motion a at a connection 37, 38, with a sleeve 36 carrying a pinion 39, and a stressed torsion spring 41 inside the tubes tends to oppose the rotation of the pinion 27 during recoil. The pinion 39 is geared as shown to a pinion 42 associated with a similar lost motion device 45, 46, with a clearance b, torsion spring 47, and tube 32, the latter carrying the star wheels 32a which engage the rounds of ammunition. The sum of the clearances a and b is less than that needed to advance a round to the breech of the firearm. Thus, on recoil, if the resistance to the feed motion is not overcome by the two springs the teeth of the two lost motion devices will engage and a positive drive to the star wheels 32a results. The links of the cartridge belt are of the disintegrating type and are stripped from the rounds as described in Specification 712,890.