| 摘要 |
<P>PROBLEM TO BE SOLVED: To prevent a sliding load from increasing due to a negative pressure generated by screw pumping action of a spiral concave and convex portion 15c, and to prevent muddy water and dust from entering from the side of an atmosphere B. <P>SOLUTION: This sealing device includes a first seal 1 whose outer diameter part 12 is closely fitted and fixed to a housing 3, having a seal lip 15 whose inner diameter edge 15a near the front end facing the side of a machine inside A is brought slidably into close contact with a rotor 4 having an approximately horizontal axis O, and a second seal 2 which is located outside the seal lip 15 and mounted on the first seal 1, having an external lip 22 which is brought slidably into close contact with the rotor 41. On the inner peripheral face of the seal lip 15, the spiral concave and convex portion 15c is formed which generates the screw pumping action toward the side of the machine inside A when the rotor 4 rotates in a fixed direction. On the axially outside and outer-diameter side of a sliding part S of the seal lip 15, a ventilation passage E is formed to allow a space D between the first seal 1 and the second seal 2 to communicate with the side of the atmosphere B. <P>COPYRIGHT: (C)2012,JPO&INPIT |
