Hot air dryer with multiple desiccant cartridges

摘要

The hot air dryer for plastic materials is disclosed. Three desiccant cartridges are carried on a rotatable turret and each cartridge is indexed successively from a process air station to a regeneration station and then to a cool down station. At each station, the cartridges are clamped between sets of upper and lower conduit fittings to provide a closed air flow path. A clamp spring acts on a lower conduit carrier to raise the cartridges against the set of upper conduit fittings to a clamped or closed position. The clamping actuator including a motor driven lead screw acts on the carrier to retract it against the resistance of the clamp spring to lower the turret and hence the cartridges away from the set of upper fittings to a stop position and the carrier is further retracted to separate the set of lower conduit fittings from the lower end of the cartridges thereby opening the clamp and the air flow path through the cartridges. A turret drive mechanism rotates the turret to the next index position and the clamp actuator closes the clamp to place the dryer in readiness for another cycle.