FLUID VAPORIZING DEVICE HAVING CONTROLLED TEMPERATURE PROFILE HEATER/CAPILLARY TUBE

摘要

A fluid vaporizing device (10) includes a capillary tube (20) made from an electrically conductive material, an upstream electrode (32) and a downstrea m electrode (34) connected to the tube (20). The downstream electrode (34) is provided with an electrical resistivity sufficient to cause heating of the downstream electrode during operation to approximately the same temperature as the tube at the point of connection. A source of material (12) to be volatilized is provided to the tube at the feed section (22), into the heate d section (24) and is vaporized, and then exits from the tube through the tip (29). The temperature profile of the tube along the heated section (24) is controlled by varying parameters to substantially eliminate any effect of th e downstream electrode (34) as a heat sink. These parameters may include the electrical resistivity of the downstream electrode (34), its cross-sectional area and its length.