Electronic cigarette

An electronic cigarette comprising a generally cylindrical housing with a proximal mouth end and a distal end, and within the housing:

• a vaporizer to produce vapor to be delivered to the mouth end;
• a battery;
• and
• sensor circuitry to detect a user drawing on the mouth end and connect the battery to power the vaporizer to produce vapor,
• the vaporizer comprising:
• a tube having inlet and outlet ends and extending longitudinally of the housing, first and second supports at opposite ends of the tube for directing airflow into and out of the tube from the inlet to the outlet, wherein the first support is located at the inlet end of the tube and the second support is located at the outlet end of the tube,
• a porous matrix containing a vaporizable liquid, extending around the tube, wicking fibers extending through side openings in the tube and configured to wick the vaporizable liquid from the porous matrix into the tube,
• an electrical heater coil in the tube configured to be powered by the battery to vaporize liquid on the wicking fibers in the tube, so that vapor is supplied along the tube to the outlet end when the user draws thereon, and
• an airflow restrictor to channel the flow of air along the tube to the heater coil, wherein the airflow restrictor is located in the tube between the first support and the heater coil.