The upper hoist (fig. 4-60) receives a round from the loaded drum and, in turn, transfers the round to the cradle for ramrning into the gun breech. Upon receiving around, the upper hoist raises it to the cradle, a pivoting tube attached to the rotating structure above deck. A pawl on the open-end chain within the upper hoist tube raises the round and then lowers it into position for the next load cycle. Also, the upper hoist can receive (unload) ammunition from the cradle. Ammunition handlers remove the round through a projectile unloading door and a powder case unloading door on The upper hoist. The lower accumulator system operates the raise cycle of the upper hoist. The upper accumulator system operates the lower cycle of the upper hoist. For example, if you have only the lower system lit off and raise the upper hoist, it will not lower until the upper system is energized.

_{Figure 4-60.-Upper hoist.}

UPPER ACCUMULATOR SYSTEM

The upper accumulator system (fig. 4-61), mounted on the carriage, provides the hydraulic power for operating the gun-loading components on the rotating structure: the cradle, the rammer, the breech mechanism, two recoil pistons, the empty case tray, and the empty case ejector. The major components of the upper accumulator system include a main supply tank, a main motor and pump, an exercise and emergency power drive, hydraulic controls, a main accumulator, and an emergency accumulator. The main supply tank also stores hydraulic fluid for the train and elevation system.

Cradle

The cradle (fig. 4-62) is a pivoting tube that transfers ammunition between the upper hoist in the loader room and the slide in the rotating structure. When in the DOWN position, the cradle aligns with the upper hoist; when in the UP position, it aligns with the _{gun bore.}

Figure 4-61.-Upper accumulator system.

Figure 4-62.-Cradle and rammer. 4-48

Rammer

The rammer, a chain-operated pawl inside the cradle, rams the round into the breech when the cradle latches into alignment with the gun bore. The gun barrel housing is a mounting block for the gun barrel, the breeze mechinanism, and the two recoil pistons (or cylinders).