Sealing device

A sealing device to be used on a rotary shaft that rotates in one direction and an opposite direction, the sealing device comprising:

• an annular reinforcing ring around an axis;
• and
• an annular elastic body piece around the axis including a seal lip and attached to the reinforcing ring, the elastic body piece being made of an elastic body,
• wherein:
• the seal lip includes a lip distal end portion that is an annular portion projecting toward the axis,
• the lip distal end portion has a sealed-side surface and an atmosphere-side surface connected to each other with a lip edge in between, the sealed-side surface being an annular surface on a sealed-object side, the atmosphere-side surface being an annular surface on an atmosphere side,
• the atmosphere-side surface is provided with a plurality of first projecting structures arranged side by side in a circumferential direction and a plurality of second projecting structures arranged side by side in a circumferential direction,
• the first projecting structures and the second projecting structures each include a first projection and a second projection adjacent to each other in the circumferential direction,
• the first projection is a projection for returning a sealed object leaking during a rotation of the rotary shaft in the one direction back to the sealed-object side by a pumping action,
• the second projection is a projection for returning the sealed object leaking during a rotation of the rotary shaft in the opposite direction back to the sealed-object side by a pumping action,
• in each of the first projecting structures, from the sealed-object side toward the atmosphere side, the first projection and the second projection approach each other without contacting one another such that a flow path is created through which the sealed object is to be returned to the sealed-object side during the rotation of the rotary shaft, and
• in each of the second projecting structures, from the sealed-object side toward the atmosphere side, the first projection and the second projection approach each other.