| 摘要 |
An electrical device for evaporating a volatile liquid (for example an air freshener) into a room employs a wick 14 which extends upwardly from a container of the volatile liquid. A ring heater 16 is in the vicinity of the end of the wick, and assists the evaporation. Vapour escapes from the device through an aperture 10 above the wick, in a casing. The vapour emission rate is controlled by a user, who operates a control member in the casing, to alter the vertical position of a tubular body 18. Vapour may flow from the wick to the exterior through the tubular body 18, and then through the aperture 10. However in all positions of the tubular body vapour may also flow to the aperture, and thence to the exterior, by an auxiliary route, not through the tubular body. It is found that the provision of this auxiliary route for vapour significantly improves the performance of the device. |
