Metering and vaporizing particulate material

1. Apparatus for metering and vaporizing a particulate material, comprising:

(a) a metering device for metering particulate material including:

(i) a reservoir for receiving particulate material;

(ii) a housing having an internal volume and having first and second openings for respectively receiving the particulate material from the reservoir and for discharging the particulate material;

(iii) a rotatable shaft disposed in the internal volume, the shaft having a smooth surface and a circumferential groove aligned with the first and second openings for receiving particulate material from the reservoir and for discharging the particulate material;

(iv) a rotating agitator with a plurality of tines disposed in the reservoir and cooperating with the rotating shaft for fluidizing the particulate material and transporting the particulate material from the reservoir into the circumferential groove;

(v) the rotatable shaft and the internal volume cooperating such that the particulate material is transported by the circumferential groove and not along the remainder of the rotatable shaft;

(vi) means disposed in relation to the second opening for scraping, and cooperating with the groove to dislodge particulate material retained therein, and in response to the shaft rotating, deliver metered amounts of particulate material through the second opening;

(vii) means in proximity to the second opening for fluidizing the particulate material at the second opening into single particulate grains, or small aggregates of particulate grains, or both; and

(b) a flash evaporator that receives and flash vaporizes the metered particulate material.

2. The apparatus of claim 1 , wherein the scraping means comprises a stationary scraper having at its end substantially the same cross section as the groove in the rotating shaft.

3. The apparatus of claim 2 , wherein the fluidizing means imparts oscillating motion to the second opening.

4. The apparatus of claim 3 , wherein the fluidizing means comprises a foil agitator moving in the plane of the second opening.

5. The apparatus of claim 3 , wherein the fluidizing means comprises an iris mechanism that changes the size of the second opening in an oscillating manner.

6. The apparatus of claim 1 , wherein the flash evaporator is rotatable.

7. The apparatus of claim 6 , wherein the flash evaporator is rotated via a magnetic coupling.