| 摘要 |
PROBLEM TO BE SOLVED: To provide a valve device 1 in a cantilever structure that is configured to open and close an EGR passage 2 through which exhaust gas from an internal combustion engine passes, and comprises lower-cost bearing means 5.SOLUTION: For bearing means 5, use of a metal bearing with high heat resistance is abolished. The bearing means 5 is constituted of two rolling bearings 13 arranged in series in the axial direction. In the rolling bearing 13 on the passage side, an air gap 18 is sealed by a rubber seal material 21 on the passage side. Thereby, the bearing means 5 is located away from the EGR passage 2 so as to inhibit the rolling bearing 13 from being exposed to heat, and airtight function of oil seal is ensured. Further, thermal deterioration of the rubber seal material 21 is suppressed by holding a large distance between the rolling bearing 13 on the passage side and the EGR passage 2. Consequently, for the bearing means 5, its performance at the same level as or higher than that of the conventional ones is ensured, and cost reduction is achieved. |
