| 摘要 |
PROBLEM TO BE SOLVED: To provide a fulcrum bearing device of a pulley arm that can secure favorable sealing performance even if pressure is raised due to a temperature change in a fulcrum bearing.SOLUTION: A boss part 4 is arranged in the pulley arm 1 that is energized in a direction in which a tension pulley presses a belt by a hydraulic automatic tensioner, a sleeve 7 is inserted into a center hole 5 of the boss part 4, washers 8 are fit to circumferences of both ends of the sleeve 7, and the pulley arm 1 is swingably supported by being fixed to an engine block by the fastening of bolts that are inserted into the sleeve 7. Seal members 12 are press-inserted into large-diameter seal accommodation recesses 11 formed at both the ends of the center hole 5. Radial lips 12c inclined toward an inside direction are arranged at the internal face of the seal member 12, and contact pressure to the outer diameter face of the sleeve 7 is raised by elastically deforming the radial lips 12c in directions in which the radial lips are contracted when internal pressure is raised. |
