ELECTRONIC VAPORISER SYSTEM

1 . An electronic cigarette vaporiser system including a piezo-electric pump that pumps e-liquid into an electronic vaporizer, in which a sensor detects whether air or e-liquid is present in the liquid feed line into the piezo-electric pump and adjusts an operating parameter of the pump accordingly.

2 . The electronic cigarette vaporiser system of claim 1 in which the operating parameter that is adjusted is the frequency of the actuators in the piezo-pump.

3 . The electronic cigarette vaporiser system of claim 1 in which the operating parameter that is adjusted is the flow-rate provide by the piezo-pump.

4 . The electronic cigarette vaporiser system of claim 1 in which the operating parameter that is adjusted is the pressure delivered by the piezo-pump.

5 . The electronic cigarette vaporiser system of claim 1 in which if the sensor detects that air is entering the piezo pump, then the piezo pump is controlled to operate at a high frequency.

6 . The electronic cigarette vaporiser system of claim 5 in which the high frequency is between 150-400 Hz.

7 . The electronic cigarette vaporiser system of claim 6 in which the high frequency is 300 Hz.

8 . The electronic cigarette vaporiser system of claim 5 in which if the sensor detects that e-liquid is entering the piezo-pump, then the piezo pump is controlled to operate at a lower frequency.

9 . The electronic cigarette vaporiser system of claim 8 in which the lower frequency is approximately 15 Hz.

10 . The electronic cigarette vaporiser system of claim 1 in which a temperature measurement device provides a further input that is used to adjust one or more of the operating parameters of the piezo-pump.

11 . The electronic cigarette vaporiser system of claim 10 in which ambient and/or e-liquid temperature is measured by the temperature measurement device or devices.

12 . The electronic cigarette vaporiser system of claim 10 in which, as the temperature measured by the temperature measurement device(s) gets lower, then the piezo pump is operated at a lower frequency.

13 . The electronic cigarette vaporiser system of claim 1 in which a viscosity measurement device provides a further input that is used to adjust one or more of the operating parameters of the piezo-pump.

14 . The electronic cigarette vaporiser system of claim 13 in which as viscosity of the e-liquid increases, then the piezo pump is operated at a lower frequency.

15 . The electronic cigarette vaporiser system of claim 1 in which the sensor includes a pair of electrical contacts on either side of the tube; and when there is e-liquid in the portion of the tube around which the sensors are placed, then there is a large resistance; when there is air in that portion, then the resistance is infinite or too high to measure.

16 . The electronic cigarette vaporiser system of claim 1 in which the sensor is a capacitive sensor.

17 . The electronic cigarette vaporiser system of claim 1 in which the sensor is an infra-red light sensor.

18 . The electronic cigarette vaporiser system of claim 1 in which the piezo-pump and sensor are in the case.

19 . The electronic cigarette vaporiser system of claim 1 in which the piezo-pump and sensor are in the vaporiser.

20 . The electronic cigarette vaporiser system of claim 1 in which the piezo-pump and sensor are in a user-replaceable cartridge.

21 . The electronic cigarette vaporiser system of claim 1 in which the electronic vaporiser is filled from a user-replaceable e-liquid cartridge.

22 . The electronic cigarette vaporiser system of claim 21 in which the electronic vaporiser is refillable with e-liquid only when inserted, whole and intact and not dis-assembled, into a re-fill case that includes a fluid transfer mechanism to transfer e-liquid into the vaporiser.