| 摘要 |
<p>PURPOSE: To reduce deposition of dust on a lead wire by optimizing the profile of the lead wire serving as an electrode and a supporting rod of a heating element. CONSTITUTION: A heating element 30 to which lead wires 32, 33 are fitted at the both ends thereof, has a bobbin 31 around which a resistor wire 35 is wound and a protective film 36 is applied thereon. Since the lead wire 32, 33 have a protrusion 100 pointed toward the upstream side of channel, change of streamline at a large angle can be prevented in the vicinity of the protrusion 100. Consequently, adhesion of dust to the front side of the protrusion 100 can be reduced and fluctuation in the accuracy of measurement due to variation of heat dissipation characteristics of the lead wire, caused by deposition of dust, can be suppressed.</p> |
