| 摘要 |
In a recoilless air gun in which opposing pistons are arranged to be propelled simultaneously in opposite directions when the gun is fired, to compress a charge of air to propel a projectile, the pistons are attached to opposing locations on an endless chain or flexible belt extending around spaced apart reversing pulleys, so that as the attachment point of one piston to the chain or flexible belt moves in one direction along one of the runs thereof between the pulleys, the attachment point of the other piston moves in the opposite direction along the other of the runs. The pistons are propelled by respective similar springs so that the effective masses of the springs are also balanced and the flexible belt or chain is required merely to ensure the desired relative positioning of the pistons and is not required to provide the accelerative and air-compressing force for either piston. The pistons may be connected to the belt or chain via respective connecting links and, in order to minimize loads on the trigger sear, the connecting rods may be arranged to be close to dead-center positions with respect to the respective pulleys in the cocked condition of the gun. |
