Patent ID: 7318589

Claim:
A sealing device comprising: a first seal ring that is fixed to an outer ring member; a second seal ring that is fixed to an inner ring member capable of relatively, coaxially rotating with respect to the outer ring member; and a magnetic sensor that is attached to the first seal ring, wherein the second seal ring includes: a metallic ring that is engaged with an outer circumference of the inner ring member; a lip that is bonded to the metallic ring, and comes into contact with the first seal ring; and a pulser ring that is provided in the metallic ring so that the pulser ring can be opposed to the magnetic sensor in the radial direction and is detected by the magnetic sensor, wherein the pulser ring includes: an annular core portion that includes an inner cylindrical portion provided on an outer circumference of the metallic ring, an outer cylindrical portion arranged coaxially with the inner cylindrical portion, and an annular plate portion for connecting the inner cylindrical portion with the outer cylindrical portion; and a multipolar magnetic rotor, in which N-poles and S-poles are alternately arranged in the circumferential direction, and which is bonded to the outer cylindrical portion.