Patent ID: 8137437

Claim:
A vapour generator comprising: a vapour chamber in which a vapour is produced, a vapour chamber inlet by which gas can enter the chamber, and a vapour chamber outlet by which vapour can flow out of the vapour chamber, and a vapour-adsorbent passage extending from the vapour chamber outlet such that all gas and vapour flowing from the vapour chamber outlet flows through the vapour-adsorbent passage and such that, when no gas is caused to flow through the generator, vapour produced in the vapour chamber flows to the vapour-adsorbent passage and is adsorbed at a rate that ensures substantially no vapour passes as far as the generator outlet but, when gas is caused to flow through the generator, the vapour is carried through the vapour adsorbent passage at a rate sufficiently high to ensure a flow of vapour from the generator outlet wherein the vapour adsorbent passage is provided by a vapour-permeable passage extending through an adsorbent means, wherein the adsorbent means includes a chamber containing an adsorbent material, and wherein the adsorbent material includes charcoal.