Patent attributes
An electronic vapor provision system includes a housing, a vaporizer contained within the housing, and a mouthpiece at one end of the system. The mouthpiece provides an air outlet. At least one air inlet hole is provided in a portion of the housing. In response to a user inhalation at the mouthpiece, air flows into the system through the one or more air inlet holes, past the vaporizer, and out through the mouthpiece. The system further includes a collar located around the portion of the housing in which the one or more air inlet holes are provided. The collar is movable with respect to the housing. The system further includes a mechanism for positively engaging the collar and the housing at a plurality of predetermined positions as the collar is moved with respect to the housing. Different ones of the plurality of predetermined positions result in different degrees of alignment between the one or more air inlet holes of the housing and the collar, thereby providing different levels of ventilation into the system.
