| 摘要 |
<P>PROBLEM TO BE SOLVED: To provide a small filter device for sensing choking of a filter. <P>SOLUTION: Air is introduced into a canister for adsorbing fuel vapor in a fuel tank. In the filter device 20 for collecting foreign matters in the air, an opening part 271 formed on one end of a sensing pipe 27 is contacted with a filter inlet surface 241 to be the inlet of the air of a filter 24. The other end of the sensing pipe 27 is connected with a pump 26 and a pressure sensor 28. The opening area of the opening part 271 is smaller than that of the filter inlet surface 241. Thereby, pressure is reduced in a sensing passage 272 formed in the sensing pipe 27 by the pump 26 for determining the choking state of the filter 24 from the pressure value sensed by the pressure sensor 28. Therefore, miniaturization of the pump 26 is enabled by alleviating the load of vacuuming by the pump 26 to enable miniaturization of the entire of the filter device 20. <P>COPYRIGHT: (C)2012,JPO&INPIT |
