Abstract: A transfer mechanism that can selectively transfer molded solid propellant charges or projectiles between a transport conveyor and respective storage magazines is described. The transfer mechanism has multiple transfer forks driven from a common drive shaft for engaging the munition(s) and selector gates driven by a gate crankshaft associated with each respective magazine for blocking or permitting the transfer controller to either transfer a projectile or one or more solid propellant charges. Each transfer fork and selector gate can be independently and selectively coupled to, or decoupled from, its respective shaft by respective coupling mechanisms under the command of a controller for coordinated transfer operation. The fork and gate coupling mechanisms, as well as a mechanism coupling the drive shaft to respective driven transfer crankshafts provide "uncoupled" positions with the respective fork or gate element or drive shaft restrained from rotary motion.

Abstract: A stepping piston is projected into the path of a slide valve drive piston to limit piston movement and thus the slide valve towards maximum unload position determined by piston bottoming out against the cylinder wall. The slide valve main drive piston stroke is also correlated to desired slide valve positions along the intermeshed helical screw rotors of the helical screw rotary compressor to provide, for example, stepped unloading at compressor full load, two-thirds full load, and one-third full load.

Abstract: A vehicle engine driven helical screw compressor for a gas refrigeration system includes a slide valve actuator for shifting the compressor slide valve to load and unload the compressor. In addition to a first solenoid operated control valve selectively connecting the slide valve actuator to compressor high side pressure to effect loading of the compressor and a second solenoid operated control for connecting the slide valve actuator to the compressor low side pressure to effect unloading, a tracking valve responsive to engine acceleration and deceleration connects the slide valve actuator to the low side pressure during engine acceleration for immediate unloading of the compressor and connects the slide valve actuator to the high side pressure during engine deceleration to immediately load the compressor.

Abstract: An air motor, responsive to change in pressure of a compressed air supply line acts to control the flow of hydraulic motive fluid to a hydraulic motor which drives the capacity control slide valve of a helical screw, rotary compressor feeding the supply line. To eliminate hunting of the slide valve which shifts in response to change in compressor load, a mechanical feedback from the hydraulic motor modulates the flow of motive fluid to the hydraulic motor.