Electrically heated cigarette smoking system with internal manifolding for puff detection

An electrically heated cigarette smoking device includes a heater unit, heater blades for applying heat to portions of a cigarette that is supported within the heater unit, the heater unit having an opening adapted to receive an end of a cigarette and adapted to position the end of the cigarette in proximity to the heater blades, and the heater unit defining at least part of a suction flow passage through which ambient air is drawn into contact with the cigarette when a smoker draws on the cigarette positioned in the heater unit. The heater unit is mounted within a partition that positions the heater unit relative to the housing and at least partially defines a bypass flow passage in fluid communication with ambient air surrounding the housing, the partition further defining a flow diverting passage leading from the bypass flow passage to the suction flow passage and through which ambient air is drawn from the bypass flow passage when a smoker puffs on a cigarette inserted in the heater unit opening. A flow sensor is positioned in the flow diverting passage to provide a signal indicative of a smoker taking a puff on the cigarette.