VENTILATOR

摘要

A ventilator (16) for controlling the local environment external to s slot (13) of a freeze dryer (10) is described. The ventilator (16) comprises a cabinet (22) located over the slot door (30) of the freeze dryer (10), a front wall (24) of the cabinet (22) facing the freeze dryer (10). An aperture (36) formed in the front wall (24) allows access to the slot (13) to enable the freeze dryer (10) to be loaded and unloaded through the cabinet (22), the ventilator (16) being provided with one or more doors (40,42,44) for opening and closing the aperture (36) as required. A fan (48) generates a controlled air stream within the cabinet (22), the air stream passing across the slot door (30). Thus, when the slot door (30) is raised to open the slot (13), only air from this controlled air stream enters the freeze dryer (10).